|Year : 2017 | Volume
| Issue : 1 | Page : 1-8
Quality of life in heart failure: A review
Saheed O Adebayo1, Taiwo O Olunuga1, Amina Durodola1, Okechukwu S Ogah2
1 Department of Internal Medicine, Cardiology Unit, Federal Medical Centre, Abeokuta, Nigeria
2 Department of Medicine, Division of Cardiology, University College Hospital, Ibadan, Nigeria
|Date of Web Publication||10-Mar-2017|
Okechukwu S Ogah
Department of Medicine, Division of Cardiology, University College Hospital, PMB 5116, Ibadan
Source of Support: None, Conflict of Interest: None
Heart failure (HF) is a major cause of morbidity and mortality worldwide. HF severity and mortality can be predicted by measurement of quality of life (QOL). Generic and disease-specific instruments for measurement of QOL have been shown to be effective in clinical settings and in research. QOL compares favorably with traditional calibrators of HF severity such as New York Heart Association (NYHA) class, left ventricular ejection fraction (LVEF), 6-min walk test (6MWT), and B-type natriuretic peptide levels. QOL measurement using domains such as social interaction, emotion, environmental interaction, sexual activity, and demographic characteristics, among others, can be used effectively in resource-limited environments, as well as adjunct to echocardiography and BNP. Lower QOL predicts early and more frequent HF hospitalization, depression, higher NYHA class, poor 6MWT, lower estimated glomerular filtration rate, and lower LVEF. Older age, lower socioeconomic status, longer duration of HF, and comorbidities correspond to lower QOL scores. Clinical trials incorporating QOL as primary and/or secondary end-point show improved QOL with the use of angiotensin receptor blockers, angiotensin-converting enzyme inhibitors, beta blockers, device therapies, such as implantable cardiac defibrillator, and exercise-based rehabilitation. The aim of this paper is to review information on QOL in HF.
Keywords: Health outcome, heart failure, quality of life
|How to cite this article:|
Adebayo SO, Olunuga TO, Durodola A, Ogah OS. Quality of life in heart failure: A review. Nig J Cardiol 2017;14:1-8
| Introduction|| |
Since the 1980s when the concept of quality of life (QOL) in health was introduced, it has received tremendous acceptance to the extent that clinical trials include it as part of outcome measures.,, It is now routinely assessed for clinical, research, and health policy decisions. It has effectively predicted the severity of heart failure (HF), morbidity and mortality as well as the cost of management.,,,,,, Because of psychological, social, emotional, and mental dimensions involved in health-related QOL (HRQOL), its assessment provided additional advantages over the traditional functional status assessment (New York Heart Association [NYHA], 6-min walk test [6MWT], and left ventricular ejection fraction [LVEF]).
QOL is viewed in a broad sense as all factors relating directly or indirectly to health status. It is a reflection of a person's mental and physical well-being in their everyday life. Because the functional status of HF patients tends to affect the domains of the QOL (physical, psychological, social, emotional, sexual, and mental well-being), it is prudent to probe into the relationship between the QOL and functional status of the patients.
The goals of treatment in patients with HF are to relieve symptoms, prevent hospital re-admission, and improve survival. Therefore, clinical trials have focused on mortality and hospital readmission as primary end-points and changes in functional status (NYHA class, 6MWT), cardiac biomarkers, left ventricular function, serum creatinine, blood urea nitrogen, and estimated glomerular filtration rate (GFR) as secondary end-points.
Recently, QOL was introduced as an outcome measure as well as a prognostic variable as many patients prefer improvement in QOL at the expense of prolonged survival. Meaningful survival indicates satisfactory QOL to the patient.
QOL reflects the way a person's physical and mental well-being is evident in their life. It measures the effect of an illness or its treatment from patients' perspective. Measurement of HRQOL promotes patient's active participation in his or her care. Determination of HRQOL is likened to blood pressure measurement in the sense that both require formal assessment are reproducible and independently predict adverse outcome.
The aim of this paper is to review information on QOL in individuals with HF with special reference to available data from Nigeria.
| Definitions of Quality of Life|| |
In 1948, the World Health Organization (WHO) defined health as “a state of complete physical, mental and social well-being and not merely the absence of disease and infirmity.” Since then, QOL issues have steadily become more important in health-care practice and research. Although there is no universally agreed definition of QOL, the WHO has defined QOL as “an individual's perception of their position in life in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards, and concerns.”
QOL is viewed in a broad sense as all factors relating directly and indirectly to health status. It is a reflection of a person's mental and physical well-being in their everyday life.
According to Schipper et al., HRQOL measures the effects of an illness or treatment from the patient's perspectives. The ranges of manifestation of disease in a given patient include symptoms, functional limitations, and QOL, in which QOL is the discrepancy between actual and desired functions.
Calman defined QOL as the gap between the patient's expectations and achievements. The smaller the gap, the higher the QOL. Conversely, the less the patient can realize his expectations, the poorer his QOL. It has also been shown that the gap between expectations and achievement may vary over time as the patient's health improves or regresses in relation to the effectiveness of treatment or progress of disease.
A related term to the QOL is health status, which means the impact of disease on patient's function as reported by the patient.
While discussing the social dimension of QOL, Siegrist and Junge defined social health as “the dimension of an individual's well-being that concerns how the individual gets along with others, how other people react to him or her, and how the person interacts with social institutions and norms.”
The three constructs QOL, HQOL, and Health Status are frequently used interchangeably in medical literature.
| Quality of Life Instruments|| |
Central to the concept of the QOL is the measurement which makes use of certain tools referred to as instruments. These instruments are basically into two categories: generic instrument and disease-specific instrument.
In general, instruments used in measuring QOL must possess the following psychometric properties-validity (if it is really measuring what it is supposed to measure), reliability (if it gives the same measurement after repeated administration in stable patients), sensitivity (if it can detect clinically meaningful differences in QOL across the broad spectrum of the clinical conditions), and responsiveness (if it detects changes when the patients' conditions change).
These are general health measures applicable to a wide range of groups, age, diseases, and cover a wide range of QOL domains., Examples are shown in [Table 1]. Among all of these, Short Form 36 (SF-36) is the most frequently used.
|Table 1: Types and examples of instruments used for the assessment of quality of life|
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These instruments are specifically designed for cardiovascular diseases (CVDs). They focus on the area of the health status specific to the cardiac disorders. They are disease, symptom, or domain specific. Examples are shown in [Table 1].
The Minnesota Living with Health Failure (MLHF) Questionnaire is the most frequently used disease-specific instrument.,
In QOL research, it is recommended that both a generic and a disease-specific instrument be combined so as to synergize the advantages inherent in each of the instruments.,
Domains of quality of life
These are aspects of behavior that are measured. These vary depending on the type of instrument used. They range from physical activity, social interaction, sexual activity, work, emotion, psychological, environmental, symptom stability, symptom burden, self-efficacy, clinical summary, gender, age, mental health, body pain, role limitations, etc.,
Medical Outcomes Study (Item Short Form 36)
The SF 36 was developed by Stewart, Hayes, and Ware in 1988 for a health insurance study by RAND Corporation. It is the most widely and extensively used generic instrument. It is used to gather information about the individual's multidimensional health concepts. It also measures a full range of domains including well-being and personal evaluations. SF-36 is suitable for use in HF trials and can be used in conjunction with disease-specific questionnaires. It has been found to be more sensitive to small degree of impairment in QOL.
SF-36 consists of eight scaled scores, which are the weighted sums of the questions in their section. Each scale is directly transformed into a 0–100 scale on the assumption that each question carries equal weight.
The eight sections are vitality, physical functioning, bodily pain, and general health perceptions. Others include physical role functioning, emotional role functioning, social role functioning, and mental health.
Two summary scores can be generated from the above which are the physical component and the mental component summaries.
Minnesota Living with Health Failure Questionnaire
The questionnaire was developed in 1984 by Rector et al. in the USA.,
The objective is to systematically and comprehensively assess the patient's perceptions of the effects of HF and its treatment on his or her daily life., It is a 21-item questionnaire using a six-point Likert scale (0–5) with score 0 (no impairment) and score 105 (maximum impairment) as a result of HF. It is the most frequently and extensively studied disease-specific instrument. MLHF assesses the patient's perception of the effects of HF on the physical, socioeconomic, and psychological aspects of life. It is, short, easy to understand, and easy to administer. It can be self- or interviewer-administered and could be completed within 5–10 min. It has high internal consistency reliability with Cronbach's alpha of 0.86.,
Quality of life and demographic profile of heart failure patients
The relationship between QOL and demographic profiles of HF patients, especially age, gender, and race are inconsistent. While some studies reported that older age is associated with higher QOL, others reported no correlation or that older age is associated with lower QOL.,,, However, recent study by Hoekstra et al. revealed that low QOL is related to older age, female gender, duration of HF, and comorbidities. Contrary to this, Mbakwem et al. found that gender did not correlate with QOL in an HF cohort in Lagos.
In a review of QOL studies in Iran between the year 2000 and 2012, men were found to have better QOL compared to women, especially in physical and mental function while increasing age was associated with significant decrease in QOL in most of the studies.
In addition, higher educational status being married and being employed had positive correlation with QOL in the majority of the studies. In contrast, longer duration of cardiac disease, frequent hospitalizations, background medical disorders (such as hypertension, diabetes, and hyperlipidemia), and family history of cardiac diseases had a significant decremental relationship to QOL.
In a recent scientific statement by the American Heart Association on measurement of patient-reported health status, it was concluded that women with CVDs had poorer QOL status. Likewise, lower socioeconomic status (SES) is also associated with worse health status.
Findings on race and ethnicity were dependent on specific disease conditions. For coronary heart disease, Blacks and Hispanic had significantly worse QOL than whites. No relationship was found between ethnicity and QOL in patients with advanced HF.
Quality of life and socioeconomic status
SES is usually assessed using the educational level, occupation, and income., Studies in the USA have shown that low SES is associated with high prevalence of risk factors, poor health education and knowledge of risk factors, late/severe presentation of CVDs, poor health-seeking behavior, and poor access to the health care. In addition, it is associated with inability to afford the medication, poor adherence to the treatment, poor follow-up, and high rehospitalization rate and mortality.,,,
Results from Atherosclerosis Risk in Communities Study indicate that people with lower SES had a 50% greater risk of developing heart disease. Therefore, being poor or having low level of education can be considered as extra risk factors for developing CVDs.
Similarly, a study from Iran showed that lower SES independently and strongly increased the risk of readmission for HF with a hazard ratio of 2.66, after controlling for the confounders.
Spertus et al. investigated the effect of the difficulty affording health care on health status. The authors found that QOL (using the Seattle Angina Questionnaire) was significantly affected at the time of coronary revascularization which persisted 6 months after the percutaneous coronary intervention in subjects who had difficulty in financing their health care. Similarly, using level of employment grade as an indicator for SES, lower grade was associated with poor physical function on SF-36 QOL questionnaire.
Heavy economic burden of HF has recently been shown from the Abeokuta HF registry, in which total cost of care was estimated to be ₦76 million translating to ₦319,000 per patient per year., In developed countries, QOL assessment had been used to predict cost of treatment over the 12 months period thereby guiding the allocation of the scarce resources in the management of cardiac diseases.,
In QOL substudy of the Eplerenone Post-Acute myocardial Infarction HF Efficacy and Survival Study (EPHESUS), health status assessment using Kansas City Cardiomyopathy Questionnaire (KCCQ) was used to predict the cost of treatment over the next 12 months with more than 300% additional cost incurred by the subjects with worst health status.
Quality of life and depression
The prevalence of depression is high among CHF patients contributing to the low QOL. A study found that the incidence of depression in an outpatient HF population was 48%, with higher rates among females (compared with males) and Whites (compared with Blacks). In addition, when compared with nondepressed individuals, depressed individuals were more likely to receive higher QOL scores on both the SF-36 and the MLHF.
Depressed individuals were also more likely to receive lower QOL scores on the KCCQ and depression remains a strong predictor of short-term decreases in QOL even after controlling for other patients' variables., This could be partially explained by poor motivation.,,
Likewise, lower QOL as measured on the KCCQ was associated with decreased medication adherence in HF outpatients and that concomitant depression seems to partially explain this correlation.
Ola et al. in Ile-Ife evaluated the relationship between depression and QOL in HF patients and found that the QOL was worse in subjects with major depressive disorder than those without depression. The factors that independently correlated with poor QOL were disability due to illness, younger age, duration of illness, and presence of major depressive disorder. The authors concluded that programs designed to improve QOL should also incorporate early detection and treatment of depression.
Quality of life and severity of heart failure
Low QOL correlates with higher NYHA functional class, poor 6MWT, and low estimated GFRs. Juenger et al. found that QOL decreases as NYHA functional class worsens (P < 0.001). Jefferson and Brofman found that QOL correlated significantly with the distance covered (r = −0.62, P = 0.004). The longer the distance covered in the 6MWT, the better the QOL.
However, the relationship with ejection fraction (EF) is inconsistent. Parajón et al. found no correlation between LVEF and QOL while Quittan et al. reported weak correlation with LVEF (p = 0.01).,
Quality of life and interventions
Pharmacologic and nonpharmacologic trials are now incorporating QOL as primary and/or secondary end-points. There are interventions that have been found to improve QOL in HF patients. Use of angiotensin II receptor blocker (candesartan), angiotensin converting enzyme inhibitor, beta blockers, device-based therapy-(Pacing, Cardiac, and Resynchronization Therapy), and exercise-based rehabilitation are known to improve QOL.,,,, Furthermore, the increase in peak oxygen uptake achieved by exercise training had been associated with an improvement in QOL  Hoekstra et al. also found that patients with low QOL are less likely to be using beta blockers.
However, in the assessment of long-term effects of irbesartan on HF with preserved EF (I-PRESERVE trial) as measured by the MLHF questionnaire, irbesartan did not substantially improve the MLHF scores after 6 months of follow-up. A controlled clinical trial also demonstrated that digoxin did not significantly improve MLHF scores compared to placebo. However, withdrawing digoxin from those already on it was associated with worsened MLHF scores compared to those who continued on the drug. Similarly, there was no significant improvement in QOL measured by MLHF in several clinical trials of calcium channel blockers in HF.,
Accordingly, interventions that improve QOL are now forming an integral component of the HF management.
Quality of life as an independent predictor of mortality
Baseline QOL is a predictor of adverse clinical outcomes such as short-term mortality, risk of early hospital readmission, and duration of hospital stay.
Konstam et al. found that the baseline QOL independently predicted mortality and HF-related hospitalizations in symptomatic and asymptomatic patients randomized to enalapril or placebo treatment in the studies of the left ventricular dysfunction. In this study, domains of activities of daily living and general health were found to predict mortality and HF-related hospitalizations in both univariate and multivariate analysis. EPidémiologie de l'Insuffisance Cardiaque Avancée en Lorraine study also found that 10-point decrease in MLHF scores assessed 4 weeks after discharge from hospital admission for HF was associated with unadjusted 23% increased risk of death and 33% increased risk of rehospitalization or death during follow-up.
Mbakwem et al. in Lagos found a negative correlation between QOL and number of hospital admissions (r = −0.167, P = 0.02). Recent work by Hoekstra et al. also found that QOL independent of BNP values predicted 3 years mortality in patients with HF. These findings indicate that QOL assessment provides additional predictive values with respect to both mortality and HF-related hospitalizations, superior to the predictive power of variables, such as EF, age, treatment, and the NYHA class.
| Studies of Quality of Life in Heart Failure Patients in Nigeria|| |
There are few studies on the QOL in Nigerian HF population., Ola et al. in 2006 investigated the relationship between depression and QOL in Nigerian outpatients with HF. One hundred HF subjects were studied. Subjects completed the WHO QOL scales brief version (WHO QOL BREF) to assess their QOL, and depression was diagnosed according to Diagnostic and Statistical Manual of Mental Health Disorders, fourth edition. The result of this study revealed the factors independently associated with poor QOL. These include disability from the illness, presence of major depressive illness, younger age, and longer duration of illness. Patients with major depressive illness were noted to have worse QOL than those without major depressive illness on dimension of physical health, psychological health, and environment.
In another study, Mbakwem et al. did a comparative analysis of the QOL of HF patients in Lagos using a generic questionnaire (WHO QOL BREF and a disease-specific questionnaire, KCCQ). The authors reported that 25% of the participants had poor QOL. There was positive correlation between the KCCQ QOL and WHO-BREF QOL score (P < 0.001), and the four domains assessed, namely, physical health, psychological, social relationship, and environment.
Furthermore, Iseko in Ibadan recently investigated the relationship between functional status and HRQOL in patients with HF. The authors concluded that 41.6% of the subjects had suboptimal QOL and that the disease-specific instrument used, MLHF demonstrated high reliability with Cronbach's alpha score (reliability coefficient) of 0.928. There were statistically significant relationship between the MLHF and the NYHA class (r - 0.776, P < 0.001) and 6MWT (r - 0.3986, P < 0.001). There was also significant relationship between LV systolic function and global QOL (r - −0.235, P < 0.005).
From the above, it is obvious that the QOL in Nigerian HF patients is significantly impaired. None of the mentioned studies has objectively compared the QOL findings in HF patients with that of healthy controls and also evaluated the correlation with the laboratory features in HF subjects.
Therefore, there is great need to further document the QOL and its correlates in HF patients in our environment.
| Conclusion|| |
QOL has been used successfully as a predictor of adverse outcome in HF. Its reliability in HF assessment and prognostication is comparable to traditional HF assessment tools such as LVEF, 6MWT, B-type natriuretic peptide, and NYHA class. Various generic and disease-specific measurement instruments have proved effective in QOL measurement in HF. Hence, its application as a tool in routine clinical assessment for HF patients at baseline and as a tool for assessing the impact of pharmacologic as well as nonpharmacologic care of HF patient is important.
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Conflicts of interest
There are no conflicts of interest.
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