DISSERTATIONS | OUTI KÄHKÖNEN | ADHERENCE TO TREATMENT OF PATIENTS WITH CORONARY... | No 440
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ISBN 978-952-61-2657-9 ISSN 1798-5706
Dissertations in Health Sciences
PUBLICATIONS OF
THE UNIVERSITY OF EASTERN FINLAND
OUTI KÄHKÖNEN
ADHERENCE TO TREATMENT OF PATIENTS WITH CORONARY HEART DISEASE AFTER A PERCUTANEOUS CORONARY INTERVENTION
This thesis investigated adherence to treatment and related factors among patients with coronary heart disease four months after percutaneous coronary intervention. Patients’
adherence to treatment was at a high level, but there was a discrepancy regarding respondents’
health behaviour and secondary prevention target values. Perceived health was lower after percutaneous coronary intervention compared with Finnish population norms. Motivation, support from physicians, and support from next
of kin were the strongest predictors of good adherence to treatment.
OUTI KÄHKÖNEN
Adherence to Treatment of Patients with Coronary Heart Disease after A
Percutaneous Coronary Intervention
OUTI KÄHKÖNEN
Adherence to Treatment of Patients with Coronary Heart Disease after A
Percutaneous Coronary Intervention
To be presented by permission of the Faculty of Health Sciences, University of Eastern Finland for public examination in Canthia 102 Auditorium, Kuopio,
on Friday, December 15th 2017, at 12 noon
Publications of the University of Eastern Finland Dissertations in Health Sciences
Number 440
Department of Nursing Science, Faculty of Health Sciences, University of Eastern Finland Kuopio
2017
Grano Oy Jyväskylä, 2017
Series Editors:
Professor Tomi Laitinen, M.D., Ph.D.
Institute of Clinical Medicine, Clinical Physiology and Nuclear Medicine Faculty of Health Sciences
Professor Hannele Turunen, Ph.D.
Department of Nursing Science Faculty of Health Sciences
Professor Kai Kaarniranta, M.D., Ph.D.
Institute of Clinical Medicine, Ophthalmology Faculty of Health Sciences
Associate Professor (Tenure Track) Tarja Malm, Ph.D.
A.I. Virtanen Institute for Molecular Sciences Faculty of Health Sciences
Lecturer Veli-Pekka Ranta, Ph.D. (pharmacy) School of Pharmacy
Faculty of Health Sciences
Distributor:
University of Eastern Finland Kuopio Campus Library
P.O.Box 1627 FI-70211 Kuopio, Finland http://www.uef.fi/kirjasto
ISBN (print): 978-952-61-2657-9 ISBN (pdf): 978-952-61-2658-6
ISSN (print): 1798-5706 ISSN (pdf): 1798-5706
ISSN-L: 1798-5706
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Author’s address: Department of Nursing Science University of Eastern Finland KUOPIO
FINLAND
Supervisors: Docent Päivi Kankkunen, Ph.D.
Department of Nursing Science University of Eastern Finland KUOPIO
FINLAND
Docent Terhi Saaranen, Ph.D.
Department of Nursing Science University of Eastern Finland KUOPIO
FINLAND
Docent Heikki Miettinen, M.D, Ph.D.
Heart Center
Kuopio University Hospital KUOPIO
FINLAND
Reviewers: Professor Riitta Suhonen, Ph.D.
Department of Nursing Science University of Turku
TURKU FINLAND
Docent Satu Elo, Ph.D.
Research Unit of Nursing Science and Health Management University of Oulu
OULU FINLAND
Opponent: Professor Elina Haavisto, Ph.D.
Department of Nursing Science University of Turku
TURKU FINLAND
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Kähkönen Outi
Adherence to Treatment of Patients with Coronary Heart Disease after A Percutaneous Coronary Intervention University of Eastern Finland, Faculty of Health Sciences
Publications of the University of Eastern Finland. Dissertations in Health Sciences 440. 2017.83 p.
ISBN (print):978-952-61-2657-9 ISBN (pdf):978-952-61-2658-6 ISSN (print):1798-5706 ISSN (pdf):1798-5706 ISSN-L:1798-5706
ABSTRACT
This survey study was conducted in five hospitals in Finland. The purpose of this study was to describe and explain adherence to treatment and related factors; perceived health, social support, and related socio-demographics, health behaviour, and disease-specific background variables among patients with coronary heart disease four months after percutaneous coronary intervention (n = 416).
The study consists of four phases. Phase I focused on testing whether or not the Theory of Adherence of People with Chronic Disease was suitable for assessing adherence to treatment among patients with coronary heart disease after percutaneous coronary intervention. Additionally, level of adherence to treatment and predictive factors were examined. Phase II concentrated on examining perceived health by patients with coronary heart disease after percutaneous coronary intervention and socio demographic, health behavioural, disease-specific background variables related to it. Phase III was conducted to explore what kind of social support did patients receive and which socio demographic, health behavioural, disease-specific background variables were related to received support.
Phase IV consisted of the model, which explained adherence to treatment and factors related to it among patients with coronary heart disease after percutaneous coronary intervention. Data analysis was conducted using multivariate statistical methods. Based on the results, the Theory of Adherence of People with Chronic Disease is a suitable theoretical framework for evaluating adherence to treatment among patient with coronary heart disease after percutaneous coronary intervention. Motivation was the strongest predictor for adherence to treatment. Other factors included: good results of care, responsibility, sense of normality, cooperation, fear of complications, and support from next of kin, nurses, and physicians. Patients’ self-reported adherence to treatment was at a high level, but there was a discrepancy regarding respondents’ health behaviour and secondary prevention target values. Perceived health was lower among patients with coronary heart disease after percutaneous coronary intervention compared with Finnish population norms. Most commonly, respondents reported pain and discomfort, problems in mobility, or anxiety and depression. Informational support was the strongest form of social support, and functional support was the weakest. Motivation, support from physicians, and support from next of kin were the strongest predictors of good adherence to treatment. Health care professionals were an important aspect to emphasise adherence to treatment, especially in women, those who were physically inactive, those with low vegetable consumption, and those without relationships. In the future, multidisciplinary studies are needed to develop evidence-based intervention to support patient adherence to treatment.
National Library of Medicine Classification:W85; WG300; WG 166.5.B2
Medical Subject Headings: Coronary Artery Disease; Percutaneous Coronary Intervention; Patient Compliance; Motivation; Social Support
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Kähkönen, Outi
Sepelvaltimotautia sairastavien potilaiden hoitoon sitoutuminen pallolaajennushoidon jälkeen Itä-Suomen yliopisto, terveystieteiden tiedekunta
Publications of the University of Eastern Finland. Dissertations in Health Sciences Numero. 440. 2017. 83 s.
ISBN (print):978-952-61-2657-9 ISBN (pdf):978-952-61-2658-6 ISSN (print):1798-5706 ISSN (pdf):1798-5706 ISSN-L:1798-5706
TIIVISTELMÄ:
Tutkimus toteutettiin viidessä suomalaisessa sairaalassa. Tutkimuksen tarkoituksena oli kuvailla ja selittää sepelvaltimotautia sairastavien potilaiden hoitoon sitoutumista pallolaajennushoidon jälkeen sekä siihen yhteydessä olevia tekijöitä; koettua terveyttä, sosiaalista tukea, sekä niihin yhteydessä olevia sosiodemografisia, terveyskäyttäytymiseen ja sairauteen liittyviä taustatekijöitä (n = 416). Tutkimus käsittää neljä vaihetta. Vaiheessa I testattiin kroonisesti sairaiden potilaiden hoitoon sitoutumisen teorian soveltuvuutta sepelvaltimotautia sairastavien hoitoon sitoutumisen arviointiin pallolaajennushoidon jälkeen. Lisäksi tutkittiin miten sepelvaltimotautia sairastavat potilaat sitoutuvat hoitoonsa ja mitkä tekijät ennustavat hoitoon sitoutumista. Vaiheessa II selvitettiin millaiseksi sepelvaltimotautia sairastavat potilaat kokevat terveytensä ja mitkä sosiodemografiset, terveyskäyttäytymiseen ja sairauteen liittyvät taustamuuttujat ovat yhteydessä koettuun terveyteen. Vaiheessa III tutkittiin, millaista sosiaalista tukea sepelvatimotautia sairastavat potilaat saavat pallolaajennushoidon jälkeen ja mitkä sosiodemografiset, terveyskäyttäytymiseen ja sairauteen liittyvät taustamuuttujat ovat yhteydessä sosiaalisen tuen saantiin. Tutkimuksen vaiheessa IV muodostettiin malli, joka selittää sepelvaltimotautia sairastavien potilaiden koettua hoitoon sitoutumista ja siihen yhteydessä olevia tekijöitä pallolaajennushoidon jälkeen. Analyysimenetelminä käytettiin monimuuttujamenetelmiä. Tulokset osoittivat, että kroonisesti sairaiden potilaiden hoitoon sitoutumisen teoria soveltuvuu sepelvaltimotautia sairastavien potilaiden hoitoon sitoutumisen arvioinnin teoreettiseksi viitekehykseksi pallolaajennushoidon jälkeen.
Motivaatio oli vahvin hoitoon sitoutumista selittävä tekijä. Muut hoitoon sitoutumista selittävät tekijät olivat hyväksi koetut hoidon tulokset, oma vastuu hoidosta, normaaliuden tunne, yhteistyö, tuki läheisiltä, hoitajilta ja lääkäreiltä sekä pelko lisäsairauksista. Potilaat arvioivat hoitoon sitoutumisensa hyväksi, mutta heidän terveyskäyttäytyminen ja riskitekijöiden hallinta ei ollut hoitosuositusten mukaisella tavoitetasolla.
Sepelvaltimotautia sairastavat potilaat kokivat terveytensä suomalaista väestötasoa huonommaksi pallolaajennushoidon jälkeen. Yleisimmät ongelmat olivat kipu, vaikeudet liikkumisessa sekä ahdistus ja masennus. Tiedollinen tuki oli vahvin sosiaalisen tuen muoto ja toiminnallinen tuki oli heikoin. Hoitoon sitoutumista selittivät voimakkaimmin motivaatio sekä lääkäreiltä ja läheisiltä saatu tuki. Terveydenhuollon ammattilaisten on tärkeää tukea erityisesti naisten, vähän liikuntaa harrastavien ja vähän kasviksia ruokavaliossa käyttävien sekä henkilöiden, jotka eivät ole parisuhteessa, hoitoon sitoutumista. Monitieteistä jatkotutkimusta tarvitaan näyttöön perustuvien hoitoon sitoutumista tukevien interventioiden kehittämiseksi.
Luokitus:W85; WG300; WG 166.5.B2
Yleinen Suomalainen asiasanasto: sepelvaltimotauti; pallolaajennus; potilaat; hoito; sitoutuminen; motivaatio;
sosiaalinen tuki
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Acknowledgements
This study was conducted at the Department of Nursing Science at the University of Eastern Finland. I wish to express my sincere gratitude to several people for providing help, guidance and support in different ways during my doctoral studies. Firstly, I would like to express my deepest gratitude to my principal supervisor, Docent Päivi Kankkunen.
Your guidance and support have been endless during this process. You have shared moments of joy and success with me, and you have also encouraged me at the time of disappointment, which is an inevitable stage in this unforgettable journey. I would like to express my warmest gratitude to my second supervisor, Docent Terhi Saaranen, for all the positive comments, support and encouragement during these years. You have also been available whenever I have wanted to ask questions or discuss any issues. I am also grateful to my third supervisor, Docent MD Heikki Miettinen. You have encouraged and helped me in many ways. I am indescribable grateful to you for challenging me to think independently and thus supporting me in widening my perspective. I am eternally grateful and privileged for having had the opportunity to collaborate with all three of you and to share this process with great specialists.
I would like to extend my sincere thanks to the pre-examiners, Professor Riitta Suhonen and Docent Satu Elo, for their careful reading and valuable comments, which helped me to improve this summary. I would also like to thank Professor Elina Haavisto most sincerely for promising to act as my Opponent. I want to express my warm thanks to Professor Helvi Kyngäs for her collaboration, support and encouragement. I would also like to thank Professor Pertti Töttö and Statistician Marja-Leena Lamidi most warmly for offering your expertise in statistics.
I am deeply thankful to the people who have made this study possible by offering practical assistance during data collection. Marja Leena Paananen and Merja Kivi from Central Finland Central Hospital, Pirkko Jussila and Irmeli Juntunen from North Karelia Central Hospital, Mari Lehtovirta and Erja Pursiainen from Päijät- Häme Central Hospital, Anne Ruotsalainen and Riitta-Liisa Heikkinen from Kuopio University Hospital, Kati Peltomäki and Virpi Räsänen from Heart Hospital Tampere, this study would have not been possible without you. I am also deeply thankful to all nurses and patients who participated in the present study. Thank you so much.
I want to express my warm thanks to my European Academy of Nursing Science (EANS) summer school scholars and colleagues for memorable times and peer support in Belgium, the Netherlands and France. I am deeply thankful for my dear friends Erja Oksman and Heli Rautiainen for your endless support and many fruitful discussions. I owe a debt of gratitude to my mother Eila. You have always encouraged me to study and go forward in life. I owe my gratitude to my late father, Timo. Although you cannot share this day with me here on earth, I believe that you are proud of me in heaven. I am thankful for my siblings Ismo, Sanna and Mikko and their families for their encouragement during these years.
I owe the deepest and most sincere thanks to my family. My daughter Anna, I hope that, in future, this thesis will encourage you to belive in yourself and to follow your dreams.
You can make them come true by being brave and working persistently, while not
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forgetting to enjoy life. My husband Asko, you have walked beside me for almost 29 years.
You have always been the greatest support for me. Thank you for your understanding and for finding the right words when I needed them to encourage me to continue. Anna and Asko, I dedicate this doctoral thesis to you; you are my everything. Thank you.
This study was supported financially by the Finnish Foundation of Cardiovascular Disease, the Aarne and Aili Turunen Foundation, and the Finnish Nursing Associations, for which I am very grateful.
In Laukaa, November 2017 Outi Kähkönen
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List of the original publications
This dissertation is based on the following original publications:
I Kähkönen O, Kankkunen P, Saaranen T, Miettinen H, Kyngäs H and Lamidi ML.
Motivation is a crucial factor for adherence to a healthy lifestyle among people with coronary heart disease after percutaneous coronary intervention. Journal of Advanced Nursing 71(10): 2364 - 2373, 2015. doi: 10.1111/jan.12708.
II Kähkönen O, Saaranen T, Kankkunen P, Lamidi ML, Kyngäs H and Miettinen H.
Predictors of adherence to treatment by patients with coronary heart disease after a percutaneous coronary intervention. Journal of Clinical Nursing. Accepted
manuscript online: 3 NOV 2017. doi: 10.1111/jocn.14153.
III Kähkönen O, Saaranen T, Lamidi M, Miettinen H and Kankkunen P. Perceived Health among Patients with Coronary Heart Disease Four Months after a
Percutaneous Coronary Intervention. International Journal of Caring Sciences 10(1):
54 – 66, 2017.
IV Kähkönen O, Kankkunen P, Miettinen H, Lamidi ML and Saaranen T. Perceived social support following percutaneous coronary intervention is a crucial factor in patients with coronary heart disease. Journal of Clinical Nursing 26(9 – 10): 1264 – 1280, 2017. doi: 10.1111/jocn.13527.
The publications were adapted with the permission of the copyright owners.
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Content
1 INTRODUCTION ... 1
2 CORONARY HEART DISEASE ... 3
2.1 Coronary heart disease: a significant public health problem ... 3
2.2 Treatment for coronary heart disease ... 5
2.2.1 Essential lifestyle treatment and pharmacotherapy for coronary heart disease ... 5
2.2.2 Revascularisation in coronary heart disease ... 8
3 THEORETICAL FRAMEWORK OF THE STUDY ... 10
3.1 Literature search ... 10
3.2 Adherence as a concept ... 10
3.3 Adherence to treatment for the management of coronary heart disease .... 12
3.4 Perceived health for the management of coronary heart disease ... 13
3.5 Social support for the management of coronary heart disease ... 14
3.6 Summary of existing literature ... 15
4 PURPOSE OF THE STUDY ... 17
5 MATERIALS AND METHODS ... 18
5.1 Study design and sample ... 18
5.2 Data, instruments and analysis ... 19
5.2.1 Adherence of People with Chronic Disease Instrument ... 21
5.2.2 EuroQoL five-dimensional scale and EuroQoL visual analogue scale instruments ... 24
5.2.3 Social Support of People with Coronary Heart Disease Instrument .. 25
5.2.4 Adherence Visual Analogue Scale Instrument ... 27
5.3 ETHICAL CONSIDERATIONS ... 28
6 RESULTS ... 30
6.1 Characteristics of the participants... 30
6.2 Testing the theory of adherence of people with chronic disease – Suitability for patients with coronary heart disease after percutaneous coronary intervention (Article I) ... 32
6.3 Predictors of adherence to treatment by patients with coronary heart disease after percutaneous coronary intervention (Article II) ... 33
6.4 Perceived health of patients with coronary heart disease after percutaneous coronary intervention (Article III) ... 35
6.5 Social support of patients with coronary heart disease after percutaneous coronary intervention (Article IV) ... 39
6.6 Modelling adherence to treatment of patients with coronary heart disease after percutaneous coronary intervention ... 42
6.7 Summary of the results ... 44
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7 DISCUSSION ... 46
7.1 Discussion of the results ... 46
7.2 Discussion of the reliability and validity of the study ... 52
8 CONCLUSIONS ... 57
9 RECOMMENDATIONS ... 58
REFERENCES ... 60
APPENDICES………..101
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Abbreviations
ACDI Adherence of people with chronic disease intrument
ACE Angiotensin-converting-enzyme ACS Acute coronary syndrome ADP Adenosine diphosphate receptor AMI Acute myocardial infarction AMOS Analysis of moment structures ARB Angiotensin reseptor blocker ASA Acetylsalicylic acid
BMI Body mass index
CABG Coronary artery bypass grafting CFI Comparative fit index
CHD Coronary heart disease CI Confidence Interval CVD Cardiovascular disease DF Degrees of freedom ECG Electrocardiogram EFA Exploratory factor analysis EQ-5D-5L EuroQoL five-dimensional scale EQ-VAS EuroQoL visual analogue scale fP-Gluk Fasting plasma glucose value GFI Goodness-of-fit index IFI Incremental fit index
LDL-C Low density lipoprotein cholesterol MeSH Medical Subject Heading
NCD Non-communicable disease NRT Nicotine replacement therapy NSTEMI Non-ST elavation infarction
OR Odds Ratio
PCI Percutaneous coronary intervention PH Perceived health
PUBMED United States National Library of Medicine
RMSEA Root mean square error of approximation
SD Standard error
SEM Structural equation modelling SPSS Statistical package for social
sciences
SSCHDI Social support for people with coronary heart disease instrument STEMI ST-elevation infarction
UAP Unstable angina pectoris VAS Visual analogue scale WHO World Health Organization
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1 Introduction
Cardiovascular diseases (CVDs) are the leading cause of death and disability among adults worldwide (Mendis et al. 2011; Piepoli et al. 2016), CVDs cause about 46% (17.5 million) of deaths from non-communicable diseases (NCDs; Mendis et al. 2011) despite the fact that preventive measures and therapies have significantly enhanced the prognoses of cardiac patients (Piepoli et al. 2016). The main reasons for this are the higher standard of living and rapidly ageing population, which increase the prevalence of NCDs. The increased incidence of NCDs is an issue of international concern. Mortality due to CVDs is estimated to grow globally by about 27% by the year 2030, which means the annual number of deaths from CVDs will be 22.7 million. CVDs account for the largest proportion (37%) of premature mortality under the age of 70 years. (World Health Organization [WHO] 2014.)
In Finland, the age-standardised mortality of coronary heart disease (CHD), which is the most prevalent disease group of CVDs, has significantly decreased over the past few decades (by 82–84% from 1972 to 2012; Jousilahti et al. 2016). However, the prevalence of CHD remains a significant public health problem (Jula et al. 2011). In the Finnish population, one third of men and one fourth of women have been diagnosed with CHD.
Among them, 54% of men and slightly more than 34% of women have been treated by invasive methods—either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI; Jousilahti et al. 2016). CVDs cause high direct medical cost; in EU about nine percent and in Finland about 12% of the total health care expenditure (Nichols et al. 2012).
Secondary prevention strategies to reduce the risk of adverse cardiovascular events include healthy lifestyle planning, which takes into account the patient’s psychological risk factors and individually designed medication regimens (Roffi et al. 2016). However, only about half of patients diagnosed with CHD are prescribed appropriate drug therapies, make the necessary lifestyle changes or participate in cardiac rehabilitation. Secondary prevention strategies and adherence to treatment are not afforded the appropriate level of importance despite the significance of these treatments for patients with CHD after undergoing PCI (Perk et al. 2012; Garcia et al. 2013; Brown et al. 2014; WHO 2014; Piepoli et al. 2016). Therefore, identifying effective evidence-based strategies to promote health and to prevent and manage chronic diseases is essential.
Many risk factors related to the development of CHD have been identified. Some risk factors, such as family history, increasing age and male gender, cannot be modified.
Nevertheless, there are numerous modifiable CHD risk factors, the most important of which are smoking, hyperlipidaemia, hypertension, abdominal obesity, diabetes, physical inactivity, an unhealthy diet, harmful alcohol consumption, and stress (Piepoli et al. 2016;
Roffi et al. 2016).In relation to sociodemographic and psychological factors, being without relationship impairs CHD patients’ prognosis and adherence to treatment (Lauck et al.
2009; Lammintausta et al. 2014). Moreover, low socioeconomic status contributes to both the risk of developing CHD and the progression of the disease (Pogosova et al. 2015; WHO 2015). These factors are related to low support and social isolation, as well as reduced adherence to treatment (Lauck et al. 2009; Lammintausta et al. 2014). The main prevention strategies for CHD recommended by the WHO (2014) are based on influencing modifiable
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risk factors, since about 75% of CVD mortality is still preventable with adequate lifestyle changes. Hence, the WHO is targeting a 25% reduction in overall mortality from NCDs including CHD by 2025 (WHO 2014).
CHD is strongly related to lifestyle, and conventional risk factors have been thoroughly studied. In recent decades, CHD and adherence to treatment (Booth et al. 2014; Perk et al.
2015), particularly adherence to medication (Ho et al. 2009; Baroletti & Dell’Orfano 2010;
Booth et al. 2014; Reuter et al. 2015), have been widely studied. Additionally, certain psychological factors have gained increased attention related to the prognosis of CHD. In particular, poor perceived health (Perk et al. 2012; De Smedt et al. 2013), and lack of social support (Barth et al. 2010), have been objects of interest. However, little is known about the relationship between these elements and their association on adherence to treatment among patients with CHD after PCI.
The purpose of this study was to describe and explain adherence to treatment and related factors; perceived health, social support, and related socio-demographics (age, gender, relationship, profession, employment status, length of education), health behaviour (physical activity, smoking, consumption of vegetables and alcohol), and disease-specific background variables (duration of CHD, previous acute myocardial infarction [AMI], previous PCI, previous CABG, systolic and diastolic blood pressure, total cholesterol and low density lipoprotein cholesterol [LDL-cholesterol]) among patients with coronary heart disease four months after percutaneous coronary intervention (n = 416).
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2 Coronary heart disease
2.1 CORONARY HEART DISEASE: A SIGNIFICANT PUBLIC HEALTH PROBLEM
CVDs are the most significant disease group globally in terms of premature mortality and the loss of quality of life (Mendis et al. 2011; Piepoli et al. 2016). CHD is a chronic CVD that progresses over the course of decades. The most common manifestations of CVDs include acute myocardial infarction and stroke (Mendis et al. 2011).
Family history in first-degree relatives (before 55 years of age men and 65 years of age in women), ageing, and male gender (Han et al. 2008) are statics risk factors for CHD (Piepoli et al. 2016). Modifiable main riskfactors for CHD are smoking, having an elevated LDL- cholesterol, and high blood pressure (Jousilahti et al. 2016). Other risk factors are metabolic syndrome, type 2 diabetes (Li et al. 2014) and physical inactivity. (Lee et al. 2012; Piepoli et al. 2016). With regard to sociodemographic and psychological risk factors, a poor perceived health (Schenkeveld et al. 2010; Grool et al. 2012), lack of social support (Barth et al. 2010) and low socioeconomic status (Alter et al. 2014), stress at work and in family life (Kivimäki et al. 2012), depression, anxiety (Pogosova et al. 2015), hostility (Chida & Steptoe 2009), and a type D personality (i.e. a stable tendency to experience a wide range of negative emotions) contribute to both the risk of developing CHD and the progression of the disease (Grande et al. 2012); they are also known to reduce adherence to treatment and to complicate lifestyle changes (Perk et al. 2012; Jousilahti et al. 2016; Piepoli et al. 2015; Stable Coronary Artery Disease: Current Care Guidelines 2015).
Worldwide, CHD mortality has decreased over recent decades in developed countries.
There is strong evidence that prevention has reduced CHD mortality by as much as 50%.
These prevention strategies, such as smoking cessation and being increasingly conscious of dietary fat intake (resulting in lower cholesterol concentrations), are aimed at changing the risk factors for CHD. According to Jousilahti et al. (2016), during the last 10 years of slightly less than two third of the reduction could be explained by changes in the three main risk factors; smoking, high LDL-cholesterol, and high blood pressure. Moreover, the treatment methods have improved significantly over the past 30 years in relation to invasive treatment and medication, which has also caused a 40% reduction in CHD mortality (Perk et al. 2012; Piepoli et al. 2016). The reduced incidence of mortality associated with acute coronary events, coupled with the ageing population, has caused the total number of people living with CHD to increase. For the majority of people, CHD develops at an advanced age, often leading to a challenging array of co-morbidities (Hemingway et al.
2006; Montalescot et al. 2013). Although the rate of mortality and the incidence of CHD have decreased considerably, the need for hospital care has increased because of the better prognosis of illness, and CHD is increasingly being regarded as an age-related disease (Perk et al. 2012).
CHD is almost invariably due to an atherosclerosis process and obstruction of the coronary arteries (Figure 1). The obstruction begins to develop in the tunica intima of the
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coronary artery, initially forming fatty deposits. As these fatty deposits increase, they begin to accumulate around the connective tissue of the artery walls, resulting in the formation of plaques and the thickening of the arterial wall (Mendis et al. 2011; Montalescot et al. 2013).
Progression of the disease process results in the obstruction of the coronary arteries, leading to an insufficient myocardial oxygen supply and cardiac ischaemia—symptoms of angina pectoris. Usually, the stenosis must be closed by approximately 50%–75% of the coronary artery lumen diameter before heart muscle ischaemia becomes noticeable. Often, this lack of cardiac muscle oxygenation will become apparent during exercise, when the heart muscle oxygen demand increases (Montalescot et al. 2013; Roffi et al. 2016).
Angina due to CHD is classified as stable angina when the symptoms (i.e. chest pain and shortness of breath) occur at the same level of physical strain. Patients with CHD often know their own maximum level of exercise to avoid symptoms, and there is usually no immediate risk of a myocardial infarction. This type of angina is usually related to a stable plaque. (Montalescot et al. 2013; Roffi et al. 2016.)
CHD can occur as an acute coronary syndrome (ACS), unstable angina (UAP), non-ST elevation infarction (NSTEMI) or ST-elevation infarction (STEMI). ACS is suspected when the symptoms worsen rapidly and appear more frequently at a lower level of exercise. This process is generally associated with an unstable plaque and may lead to a myocardial infarction with damage to the heart muscle if the arterial plaques damage and rupture, initiating intra-arterial clotting and partial or complete occlusion of the coronary artery.
This thrombus occluding the coronary artery results in myocardial infarction (Roffi et al.
2016). About 40% of coronary events result in death, and a significant proportion of deaths occur before hospitalisation. The condition in question is a medical emergency that requires immediate and aggressive treatment to prevent progression to a full-blown myocardial infarction (Roffi et al. 2016).
The diagnosis of CHD is based on the patient’s reported symptoms, clinical findings and electrocardiogram (ECG). The final diagnosis is based on an assessment of the patient’s troponin levels, a potential biological marker of myocardial injury. Unstable angina refers to the severity of coronary syndrome with ischaemic ECG, but without the elevation of myocardial markers. The diagnoses between NSTEMI and STEMI is based on the presence or absence of ST elevation and elevated troponin markers. Identification of the STEMI is important to avoid delays in patient treatment aimed at reperfusion (Montalescot et al.
2013; Roffi et al. 2016). PCI (or pharmacological reperfusion by thrombolysis) should be performed as early as possible, preferably within 12 hours of symptom onset. However, in the case of NSTEMI, patient care is determined based on a risk assessment, with a high-risk patient undergoing angiography within two to three days and low-risk patients receiving diagnostic examination as outpatients (Roffi et al. 2016).
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Figure 1. Coronary arteries: Figure A: normal artery with normal blood flow. Figure B: an artery with plaque build-up. (Source: National Heart, Lung, and Blood Institute, National Institutes of Health.)
2.2 TREATMENT FOR CORONARY HEART DISEASE
2.2.1 Essential lifestyle treatment and pharmacotherapy for coronary heart disease
The pathogenesis of CHD may follow a unique pathway for each patient, and it is treatable with several methods. Nonetheless, the starting point for treatment is the correct diagnosis and an assessment of why the patient experiences chest pain. At this time, it is necessary to determine the severity of CHD and the condition of the myocardium, factors that substantially affect the choice of treatment (Montalescot et al. 2013; Roffi et al. 2016).
Once the diagnosis is ensured by clinical testing or by coronary catheterisation, proper treatment should be given, including individually tailored smoking cessation, physical exercise, diet, medication with aspirin, beta-blockers or cholesterol-lowering drugs, PCI with or without stenting, or CABG. In summary, there are three main treatment groups for CHD: lifestyle treatment, medication, and revascularisation with PCI or CABG. It is worth noting that the treatment methods are not mutually exclusive; rather, they complement each other (Montalescot et al. 2013; Roffi et al. 2016).
These methods constitute the cornerstones of the treatment of CHD from the acute phase onwards; they are also an important part of secondary prevention. The attendance of CHD is indicated by the incidence of angina pectoris, myocardial infarction and the history of coronary artery procedures. Patients with CHD are at considerable risk for cardiac events and premature death. It is vital to understand the chronic nature of CHD and the need for adequate secondary prevention strategies to reduce the risk of adverse cardiovascular events; such strategies include leading a healthy lifestyle as a form of lifestyle treatment and adherence to an individually designed medication regimen (Piepoli et al. 2016; Roffi et al. 2016).
With respect to lifestyle treatments (Table 1), smoking cessation is of utmost importance, and patient education should be intensive during hospitalisation and should continue for at least one month after discharge. Aids to smoking cessation can be used, such as nicotine replacement therapy (NRT), which is safe in the context of ACS and should be offered to all
6
patients upon initial hospitalisation (Ludvig et al. 2005; Montalescot et al. 2013; Stable Coronary Artery Disease: Current Care Guidelines 2015; Ibanez 2017). Physical exercise should be individually tailored, taking into account the patient’s overall health status. Most patients can safely perform limited exercises 7–14 days after primary PCI for STEMI at an exercise intensity of 70%–85% of the peak heart rate. Physical exercise is recommended for at least 75 – 150 minutes per week (Perk et al. 2012; Montalescot et al. 2013; Roffi et al. 2016;
Ibanez et al. 2017).
Healthy eating habits include the consumption of at least 5 dl per day of vegetables (Stable Coronary Artery Disease: Current Care Guidelines 2015, and alcohol consumption should be limited to one to two drinks per day (Ibanez et al. 2017). Physical exercise and diet are aimed at achieving and maintaining a normal body weight and blood glucose level, and they are integral to the lifestyle treatment of CHD. Patients should aim for a self- measured fasting plasma glucose (fP-Gluck) value of less than 7 mmol/l. With regard to diabetes, the HbA1c target is < 7.0%. The desirable body mass index (BMI) is 18.5–25 kg/m2. For overweight patients, the BMI target is 25–29.9 kg/m2; for obese patients, the BMI target is over 30 kg/m2 or simply to reduce weight permanently by 5%–10%. Healthy lifestyles are likewise related to a targeted blood pressure under 140/90 mmHg and to cholesterol LDL- cholesterol < 1.8 mmol/l (Stable Coronary Artery Disease: Current Care Guidelines 2015).
Table 1. Main categories of lifestyle treatment in coronary heart disease (Ibanez et al. 2017; Piepoli et al. 2016).
Smoking cessation
Physical exercise
Diet Weight Alcohol
consumption
Follow-up Nicotine
replacement therapy Bupropion Varenicline
Participation in an exercise- based rehabilitation programme Moderate intensity: 150 min week or Vigorous intensity: 75 min per week or
combination of both performed in session with a duration at least 10 minutes
Saturated fat max 10% of total energy Salt intake <
5 g per day Fiber 30 – 45 g per day Fruits and vegetables ≥ 400g per day Fish 1 – 2 times per week Unsalted nuts 30 g per day
BMI 20 – 25 kg/m2
Limited alcohol consumption 1 – 2 portions per day: 20 g daily for men, 10 g daily for women Moderate alcohol consumption in abstainers is not
recommended
1 – 2 months after PCI Written treatment plan In future, every 6 – 12 months
While medication regimens (Table 2), are individually tailored to each patient, statins, aspirin, beta-blockers and angiotensin-converting-enzyme inhibitors (ACE inhibitors) are generally included. Statin therapy, in conjunction with a healthy diet, is the primary recommended pharmacotherapy for lowering blood LDL-cholesterol. Other recommended
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therapies include antithrombotic therapy such as low-dose aspirin (75–100 mg/day) to avoid platelet aggregation, as well as adequate antihypertensive medication (beta-blockers, ACE inhibitors or angiotensin reseptor blockers [ARBs]) to reduce and maintain the patient’s blood pressure. In mild cases of chest pain, short-acting nitro-glycerine might be considered as a standalone treatment. In patients who are more prone to recurrent chest pain, however, beta-blockers, in addition to either a long-acting nitrate or calcium channel blocker, might be considered to prevent the reoccurrence of chest pain (Montalescot et al.
2013; Stable Coronary Artery Disease: Current Care Guidelines 2015; Roffi et al. 2016).
These pharmacotherapy approaches are aimed at alleviating the patient’s symptoms of angina pectoris. While these approaches are not always successful, the patient should at least experience sufficient pain relief to minimise restrictions on their quality of life. Care should be taken to ensure that pharmacotherapies do not cause any undue side effects or impede the patient’s performance. While pharmacotherapy is almost always initiated as the first line of treatment, as well as an important part of secondary prevention, this is only a prelude to often needed invasive investigation and treatment of the patient’s CHD.
A crucial factor of the treatment after PCI is a continuum of care following discharge.
According to the guidelines (Stable Coronary Artery Disease: Current Care Guidelines 2015), the first follow-up visit of these patients should happen one to two months after discharge. The guidelines recommend making a written treatment plan, assessing risk factors and noting the patient’s psychological presentation, including signs of depression and anxiety, to ensure adequate follow-up support. Long-term follow-up monitoring should be conducted at least every 6–12 months and include medication assessment and dosage adjustment as necessary, the assessment of possible depression, and the evaluation of working and driving capacities (Stable Coronary Artery Disease: Current Care Guidelines 2015).
Secondary prevention strategies are aimed at the control of risk factors and include direct therapeutic interventions that protect coronary arteries from the progression of the disease (Giannuzzi et al. 2008; Montalescot et al. 2013; Roffi et al. 2016). Ultimately, the goal of the treatment is to influence the prognosis of the disease by subtracting from the risk of myocardial infarction and adverse cardiovascular events and by reducing the recurrence of CHD and decreasing coronary mortality in patients with established CHD. This objective is pursued by preventing the progression of atherosclerosis, stabilising existing plaques and reducing the risk of thrombosis due to plaque rupture (Stable Coronary Artery Disease:
Current Care Guidelines 2015; Roffi et. al. 2016). The effective treatment of CHD improves not only the prognosis, but also the cost-effectiveness of health care (Piepoli et al. 2016).
Table 2. Main categories of pharmacotherapy in coronary heart disease (Roffi et al. 2016).
Antithrombotic drugs Anti-ischaemic drugs
Antihypertensive drugs Lipid-lowering drugs
ASAa Nitratesb Diureticsa Statinsa
Heparin Beta-blockersa Beta-blockersa
ADP inhibitorsa ACE inhibitors/
AR blockersa
ACE inhibitors/
AR blockersa
Calcium-channel blockersb Calcium-channel blockersb
a) Improve prognosis; b) Relieve symptoms; Abbreviations: ASA = acetylsalicylic acid; ADP = adenosine diphosphate receptor inhibitors; ACE = angiotensin-converting-enzyme inhibitors; AR = angiotensin reseptor blockers.
8 2.2.2 Revascularisation in coronary heart disease
PCI (Figure 2) and CABG (Figure 3), both revascularisation procedures, offer relief from angina and result in considerable improvement in the overall health status of patients with CHD. The use of PCI has increased steadily over the past decade. PCI is an effective, safe, less invasive and more economical revascularisation treatment compared with CABG. PCI is rapidly becoming the treatment of choice for CHD because it leads to a more rapid recovery and short-term improvements in overall health status (Wong 2007; Cohen et al.
2011; Roffi et al. 2016). PCI also reduces the need for anti-angina drugs, improves survival and increases the quality of life (Roffi et al. 2016).
PCI is usually performed immediately following coronary angiography, generally as part of the same procedure. The procedure can be performed just as well through either the radial or femoral artery. (Karjalainen & Romppanen 2016; Roffi et al. 2016.) PCI involves the insertion of a soft-tipped, thin-walled guide catheter through the mouth of the coronary artery. A guide wire is inserted through the catheter and transported close to the obstruction of the coronary artery. Following X-ray fluoroscopy, a contrast agent–filled balloon catheter is inserted and expanded. The desired degree of balloon inflation is determined such that the expanded ball diameter will be equal to the diameter of a healthy portion of the vessel. While 4–12 atmosphere will usually suffice, in some situations, the balloon’s inflation pressure may exceed 20 athmosphere. (Ylitalo et al. 2016.) Because of the risk for restenosis following PCI, a stent will be installed to keep the walls of the vessel from collapsing (Roffi et al. 2016).
In many cases, the patient can be discharged on the same day following a successful procedure. While short-term hospitalisation is inherently more cost-effective (Kotowycz et al. 2010; Patel et al. 2010), post-discharge care is ultimately the responsibility of the patient (Lauck et al. 2009). Poor patient education and discharge planning can lead to a diminished understanding of the significance of CHD and a reduced understanding of risk factors, adversely affecting adherence to treatment (Fernandez et al. 2009; Lauck et al. 2009; Garcia et al. 2013).
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Figure 2. Revascularisation: percutaneous coronary intervention. (Source: National Heart, Lung, and Blood Institute, National Institutes of health.)
Figure 3. Figure A shows the location of the heart. Figure B shows how vein and artery bypass grafts are attached to the heart. (Source: National Heart, Lung, and Blood Institute, National Institutes of health.)
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3 Theoretical framework of the study
3.1 LITERATURE SEARCH
The literature was searched and reviewed during the study process several times. Peer- reviewed original research articles or literature reviews published in English between January 2004 and April 2017, which addressed the phenomenon in question, were accepted in the literature search. The literature search was performed using PubMed, Scopus and Cinahl (Ebsco) databases. The search focused on each main concept separately according to the phase of the study. The search of the literature was initially begun in 2014 when the articles were written. The first literature search focused on the theoretical aspects of adherence as a concept. The literature on the practical considerations of adherence to treatment of patients with CHD was then examined. (Phase I; Articles I and II.) Following this, the literature was searched to find accounts of the perceived health of patients with CHD (Phase II, Article III). The fourth literature search focused on the social support of patient with CHD (Phase III, Article IV). During the publication process between January 2015 and April 2017, the latest literature was added to the article in question.
The final literature search was conducted using systematic search strategy (Appendix 1, Table 3) in April 2017 in order to get deepen understanding and to include the latest studies of existing knowledge to the summary of the thesis. In the first phase of selection, the titles of retrieved articles were read and assessed for relevance to the topic of the phase of the study. Then the relevance of abstracts and full text of the chosen articles were evaluated, and duplicates were removed. (Burns & Grove 2009.) Furthermore, Clinical Practice Guidelines and Scientific Statements of the European Society of Cardiology, Current Care Guidelines of the Finnish Medical Society Duodecim, and WHO Statements were manually searched regarding CHD and its riskfactors and tretment. Finally, 135 articles were
selected. The essential studies concerning theoretical framework of this study are presented in the Appendix 2, Table 4.
3.2 ADHERENCE AS A CONCEPT
Adherence has been studied extensively in various aspects of science, such as medicine, nursing science, psychology and health economics. There is no commonly accepted definition of adherence, and the terminology has evolved over time. In response to the confusion over the concept of adherence, alternative concepts such as compliance, concordance, cooperation and therapeutic alliance have been proposed and used (Kyngäs et al. 2000a; Bissonette 2008; Cohen 2009; Snowden et al. 2013; Chakrabarti 2014; Rafii et al.
2014).
These different concepts and definitions have received criticism. Compliance was used for a long time in a wide range of sectors. As an abstract and complex concept (Kyngäs et
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al. 2000a), it is currently understood from the perspective of nursing science to involve patients as powerless recipients of care who passively follow orders (Cohen 2009; Selzer 2013; Gardner 2014; Chakrabarti 2014; Rafii et al. 2014). Adherence is defined as persistence in the practice and maintenance of desired health behaviours, and it is the result of active participation and agreement (Carpenter 2005; Cohen 2009; Selzer 2013; Chakrabarti 2014).
Adherence and compliance connote a behaviour undertaken by the patient as a result of a health consultation. Such behaviour can take many forms, including medication and making dietary changes (Bissonette 2008; Selzer et al. 2013). Compared with compliance, adherence relies on a more therapeutic contract between the patient and health care professionals. The concept of adherence emphasises communication and cooperation, as well as the patient’s role as a partner of health care professionals in decision making that concerns their own health (Gould et al. 2010; Gardner 2014).
In an effort to highlight the communication and collaboration between health care professionals and patients regarding treatment and continuous assessments, a number of experts have replaced the terms adherence and compliance with concordance (DeMaria 2012;
Snowden et al. 2013). If adherence is described as a partnership, then concordance is more like a coaching relationship in which self-care commitment is based on equality between patients and health care professionals, and patients can independently solve the problems of their care based on their knowledge of the disease (Routasalo & Pitkälä 2009; Chakrabarti 2014).
The lack of a commonly accepted definition of adherence causes several challenges when comparing different studies, which has led to the use of many alternative terms (Bissonette 2008; Rafii et al. 2014). In this study, the concept of adherence is used because patients with CHD after PCI need knowledge as well as partnership and cooperation with health care professionals after the procedur. Adherence is understood and defined as an active, intentional and responsible process of care (Kyngäs 1999) in which patients with chroninc conditions work to maintain their health in collaboration with health care professionals.
Adherence to treatment includes items measuring adherence to medication and adherence to a healthy lifestyle (diet, exercise, smoking and alcohol consumption). Additional factors associated with adherence to treatment have also been studied. According to Kyngäs´
Theory of Adherence of People with Chronic Disease (1999), the explanatory factors of adherence to treatment are responsibility, cooperation, sense of normality, motivation, results of care, support from next of kin, support from nurses, support from physicians and fear of complications (Kyngäs 1999; Kyngäs et al. 2000).This theoretical framework has been the basis of research on adherence in different adolescent and adult patient groups. In particular, motivation (Kyngäs 2002; Kääriäinen et al. 2013; Ylimäki et al. 2014), results of care (Kyngäs 2000b), support from next of kin, nurses, and physicians (Kyngäs & Rissanen 2001; Lunnela et al. 2013) have been shown to explain chronic disease patients’ adherence to health regimens.
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3.3 ADHERENCE TO TREATMENT FOR THE MANAGEMENT OF CORONARY HEART DISEASE
Adherence to treatments, including healthy lifestyle and appropriate medical treatments, is a cornerstone of reducing CHD progression and adverse events (Baroletti & Dell’Orfano 2010; Booth et al. 2014; Windecker et al. 2014; Piepoli et al. 2016). However, the prevalence of nonadherence regarding medication (Aghabekyan et al. 2012; Chowdhury et al. 2013) and a healthy lifestyle (Booth et al. 2014) is estimated to range from 30% to 60% among patients with CHD after PCI. Poor medication adherence causes almost one tenth of all cardiovascular events. Good adherence to cardiac medication is associated with 20% lower cardiovascular mortality and a 35% reduced risk of all-cause mortality. The major reasons for nonadherence to medication are socioeconomic, communication-related and motivational factors (Baroletti & Dell’Orfano 2010), such as poor knowledge, negative perceptions of medication, side effects and cost (Chowdhury et al. 2013).
The prognosis of CHD is related to a healthy lifestyle, the most important aspects of which are smoking cessation (Booth et al. 2014; Jousilahti et al. 2016),engaging in physical activity (Bäck et al. 2008; Anderson & Taylor 2014) and adhering to a recommended diet (Booth et al. 2014).However, despite the strong evidence, a large majority of patients with CHD after PCI do not achieve the guideline standards for secondary prevention (Cooney et al. 2013; Garcia et al. 2013; Kotseva et al. 2016). Numerous studies have reported persistent smoking (16%–20%) among patients with CHD after PCI (Chen et al. 2006; Budnik &
Opolski 2015; Perk et al. 2015; Kotseva et al. 2016). Between 36% and 60% of patients with CHD after PCI have a low level of physical activity (Budnik & Opolski 2015; Perk et al.
2015; Kotseva et al. 2016), which, together with insufficient changes in nutritional habits, contributes to metabolic disorders, obesity, hypercholesterolaemia and hypertension (Kotseva et al. 2016). In addition, the failure to make lifestyle changes, misunderstandings regarding CHD and cardioprotective lifestyle are common. Many patients with CHD after PCI do not know their risk factors and even believe that limiting physical activity is beneficial (Budnik & Opolski 2015). The lifelong chronic nature of CHD is difficult to understand; many patients (38%–67%) believed they were cured, and 38% perceived no need to make lifestyle changes (Lauck et al. 2009; Perk et al. 2015).
The foundations of good adherence to treatment among patients with CHD after PCI include cooperation with health care professionals, an understanding of the disease and its risk factors, knowledge of the indications and consequences of nonadherence, perceived health benefits and an understanding of the importance of medications (Rushworth et al.
2012; Housholder-Hughes et al. 2015). Cardiac rehabilitation programmes would be an adequate way to respond to the challenge to improve patients’ knowledge (Ghisi et al.
2015). However, less than half of patients with CHD after PCI throughout Europe participate in rehabilitation (Perk et al. 2015; Kotseva et al. 2016).
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3.4 PERCEIVED HEALTH FOR THE MANAGEMENT OF CORONARY HEART DISEASE
Perceived health is the subjective dimension of health, which is influenced by how a person’s life is affected by the disease, treatment effectiveness and physical symptoms. The concept reflects people’s overall perceptions of their own health, including both physical and psychological dimensions (OECD 2010). The concept of Perceived health reflects the WHO’s concept of health as a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity (WHO 1948). Although this definition of health is more utopian and difficult to operationalise, it forces one to think about well-being in terms of a broader health status (Morgan 2009; Skodova et al. 2011). Perceived health as a concept does not have an entirely unambiguous definition. It is often used as synonymous with the concepts of self-rated health, health status and perceived health status, and it is strongly related to the terms well-being and health-related quality of life (Cepeda-Valery et al. 2011). In this study, perceived health is used to describe individuals’
perceptions of their own health and health-related quality of life (De Smedt et al. 2014a).
Over the years, how individuals perceive their health has gained attention, especially in long-term chronic conditions, where full recovery is unlikely. Many patients consider the quality of the additional life years gained to be as important as the length of life (Cepeda- Valery et al. 2011). A subjective assessment of perceived health is widely used as a health indicator in population health surveys. Perceived health is consistent with objective health status and can serve as a global measure of health status in the general population. It has also proven to be a strong predictor of functional capacity, health care use and institutionalisation, as well as mortality in the general population (Prättälä et al. 2011).
Perceived health has become increasingly important as an outcome measure among patients with CHD because poor perceived health has been shown to predict mortality independently of the presence and severity of disease and risk factors (Schenkeveld et al.
2010; Grool et al. 2012; Rutledge et al. 2012) and morbidity (Schüz et al. 2011; Grool et al.
2012). Perceived health also strongly predicts long-term clinical outcomes in patients with CHD (Cepeda-Valery et al. 2011).
Patients with CHD often suffer from impaired perceived health (De Smedt et al. 2013).
De Smedt et al. (2013) examined factors associated with perceived health across 22 European countries in the EUROASPIRE III survey. They found that female gender, older age, lower education, myocardial infarction or ischaemia as recruiting diagnosis, a history of stroke, and experience of a recurrent CHD event were related to lower perceived health and quality of life. As for lifestyle, current smoking, central obesity, lack of exercise and inappropriate HbA1c control in patients with diabetes reduced perceived health significantly; thus, lifestyle risk factors are important determinants of perceived health (De Smedt et al. 2013). Lifestyle changes such as smoking cessation, increasing physical activity and adopting a healthy diet improved perceived health and the quality of life significantly (De Smedt et al. 2014a).
PCI is currently considered the most effective method for treating ACS. PCI seems to reduce mortality and ischaemic events (Blankenship et al. 2013) and improve the quality of life among patients with CHD (De Quadros et al. 2011; Blankenship et al. 2013; Chaudhury
& Srivastava 2013). However, poor perceived health has been shown to predict mortality
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among patients with CHD after PCI; thus, patient-rated health is an important means by which to identify high-risk patients in clinical practice (Schenkeveld et al. 2010).
Additionally, poor to moderate perceived health seems to be an important outcome predictor of unplanned rehospitalisation after coronary revascularisation with PCI or CABG (Benzer et al. 2016). These results highlight the importance of including patients’
subjective experience of their own health status in the evaluation strategy to optimise risk stratification and management in clinical practice (Grool et al. 2012).
3.5 SOCIAL SUPPORT FOR THE MANAGEMENT OF CORONARY HEART DISEASE
According to Cohen and Wills’ (1985) theory, social support consists of informational, emotional and functional support.Based on this theory, the dimensions of social support are defined as follows in this study: Informational support occurs when people receive information, feedback and recommendations. Emotional support is provided by listening to another person, providing care and encouragement, and appreciating their trust. Functional support includes counselling, offering one’s time, and assisting and caring for those who have trouble with coping (Cohen & Wills 1985; Madan et al. 2012). Finfgeld-Connett (2005) defined social support as a dynamic interpersonal process, centred on the reciprocal exchange of information, which changes across contexts. Social support is manifested between providers and recipients; depending on its context, social support might appear multifaceted (Finfgeld-Connett 2005).
Patients may encounter several uncertainties and stressful factors in situations where their health status has changed or is threatened (Cutrona & Russel 1990; Pisanti et al. 2014), such as in an acute cardiac event. According to Cutrona and Russel (1990), the importance of social support is emphasised in an acute situation in a stressful life event, when the social network brings out security, a feeling of love and a sense of belonging to a community (Cassar & Baldacchino 2012; Aazami et al. 2016).
The protecting mechanism of social support has been used to explain relations among stressors, social support and psychological distress. According to the main effect theory, social support promotes health directly under any circumstance, whereas buffering theory states that social support promotes health indirectly by moderating adverse stress effects (Cohen & Wills 1985). The main effect model considers stressors and the lack of social support to have direct and independent effects on psychological distress. Alternatively, the stress-buffering model posits that social support protects individuals against the harmful outcomes of stressors (Pisanti et al. 2014). Social support seems to alleviate vulnerabilities, possibly through its effects on other psychosocial factors, such as encouraging efficient coping strategies, and through its effects on several neurobiological factors (Ozbay et al.
2007).
A low level of social support is considered an independent risk factor for CHD in healthy individuals, and it reduces the good prognoses among people diagnosed with CHD. Strong evidence has shown that low levels of support are strongly associated with higher mortality in patients with CHD (Barth et al. 2010; Roohafza et al. 2012; Compare et al. 2013). A major reason for these results is the benefits of social support with regard to health behaviours.
People with high levels of social support probably smoke less (Hilding & Frilund 2004;
