| Abstract|| |
Background: Psychiatric morbidity and Health Related Quality of Life (Hr-QoL) in Ischemic Heart Disease (IHD) are relatively less studied in our country.
Aims: This cross-sectional observational study was undertaken to assess the common psychiatric disorders and Hr-QoL in IHD.
Materials and Methods: One-hundred and thirty patients with IHD were evaluated for psychiatric morbidity and Hr-QoL. Tools used were SCID-1, Euro QoL-5D, and Socio-demographic data sheet. The data were analyzed using SPSS v 10.0 software, Chi-square test, T-test, ANOVA were used as needed.
Results: Psychiatric morbidity was assessed using psychiatric assessment schedule SCID-I for generating diagnosis as per DSM-IV criteria. Major depressive disorder was found in 34.6% (n=45) patients. 23.8% (n=31) patients had a diagnosis of depression due to general medical condition. Anxiety disorder due to general medical condition was present in 36.9% (n=48) patients. Around 95.4% of patients reported psychiatric symptoms, either depression or anxiety. Though widely disputed, low educational status was reported as significantly associated with psychiatric morbidity in IHD. Female sex of the patient and the presence of diabetes mellitus were associated with psychiatric morbidity in a significant manner. Majority of patients with poor quality of life were in the domain of anxiety/depression.
Conclusion: The findings of our study reveal a high rate of psychiatric morbidity and impaired quality of life in IHD Patients.
Keywords: Anxiety, cardiovascular, depression, ischemic heart disease, IHD India
|How to cite this article:|
John S. Prevalence and pattern of psychiatric morbidity and health related quality of life in patients with ischemic heart disease in a tertiary care hospital
. Indian J Psychiatry 2013;55:353-9
|How to cite this URL:|
John S. Prevalence and pattern of psychiatric morbidity and health related quality of life in patients with ischemic heart disease in a tertiary care hospital
. Indian J Psychiatry [serial online] 2013 [cited 2020 Feb 28];55:353-9. Available from: http://www.indianjpsychiatry.org/text.asp?2013/55/4/353/120554
| Introduction|| |
Ischemic heart disease (IHD) is no longer confined by geographical area or by age, sex, or socioeconomic boundaries. Heart disease has already reached epidemic proportions in poorer countries. Of the 45.0 million adult deaths reported worldwide in 2002, three-quarters (32 million) were due to non-communicable diseases. Globally, IHD was the leading killer in the age group ≥60 years, and, with 1 332 000 deaths in adults aged 15-59 years.  Asian Indians residing in different countries have higher rates of incidence, hospitalization, prevalence, morbidity, mortality, and case fatality from IHD than people of other ethnicity. , Psychological problems associated with IHD have been studied including the prevalence of psychiatric disorders, their predictors, and quality of life. Complex multidimensional relationships exist among depression and IHD. Depression is recognized as an independent risk factor for the development of IHD as well as a significant predictor of higher morbidity and mortality in patients with symptomatic IHD.  The etiology of IHD is multi-factorial. Risk factors include modifiable ones like cigarette smoking, high blood pressure, elevated serum cholesterol, diabetes, obesity, sedentary habits, and stress. ,, The non-modifiable risk factors include increasing age, male sex, family history, and genetic disposition. ,
Increased IHD risk associated with depression was also found in a 6-year study of 4493 elderly Americans (age ≥ 65 years) who were free of IHD at baseline.  In a Spanish study,  authors analyzed the psychiatric morbidity and IHD in a consecutive series of 194 patients with IHD. The results demonstrated a high prevalence of psychiatric morbidity (44.8%) in patients with cardiological pathology in contrast to another study using a similar methodology (prevalence=35%). 
During the past three decades, quality of life (QOL) has emerged as an important attribute of clinical outcome and patient care. A study has attempted to identify clinical, demographic, and psychosocial characteristics of patients at admission that were independent predictors of QOL 6 months and 1 year after acute myocardial infarction.  They measured physical and mental QOL (Short Form-36 Physical and Mental Components Summary Scores) and overall QOL (Euro QOL health perception scale) in a prospective cohort of 587 patients. The results suggested that age and psychosocial characteristics at baseline are the most important predictors of QOL after acute myocardial infarction. Authors suggested routine measurement of QOL and the level of depression at the time of admission for myocardial infarction to target treatment interventions that can improve QOL for patients with the lowest scores. Another study evaluated the association between a history of depression and patient reported angina frequency, physical limitation, and QOL 7 months after discharge from the hospital for acute coronary syndrome.  Out of 1957 patients, 526 patients (26.7%) had a history of depression. Authors found a strong association between a history of depression, heavier angina burden, and worse QOL after an acute coronary syndrome. The presence of depression at entry point as a powerful predictor of QOL among survivors of myocardial infarction was reported by other studies also. , Apart from depression, effect of anxiety on QOL in patients hospitalized for acute myocardial infarction was also studied. One such study reported that symptoms of anxiety and depression did predict QOL among those who lived to 12 months after acute myocardial infarction.  This finding confirmed the previous similar report. 
Psychological and psychosocial factors play important roles in the etiology course and outcome of IHD. The importance of psychological factors was even more evident when attempts were made to rehabilitate IHD patients. Changes in psychological factors in patients with IHD have been found to be important determinants for improvement. The disease can directly affect the mental function and result in chronic impairment in mental function. By so far, the most commonly reported emotional consequences associated with IHD are depression, anxiety, certain psychosocial work characteristics, social networks and social support, and type A personality behavior plus hostility.  These psychosocial components are important in the secondary prevention of IHD apart from their role in primary and primordial prevention. Understanding the interplay between psychosocial factors and IHD is crucial in understanding QOL in IHD. 
| Aims and Objectives|| |
The aim of the study is to assess the psychiatric morbidity and QOL in coronary heart disease (IHD).
1. To assess prevalence and patterns of psychiatric morbidity in patients with IHD
2. To assess health related QOL in patients with IHD
3. To assess the relationship among socio-demographic and clinical factors, psychiatric morbidity, and health related QOL in patients with IHD.
| Materials and Methods|| |
The sample comprised patients with coronary heart disease. The following diagnoses are included under the heading of coronary heart disease: (1) myocardial infarction with ST segment elevation, (2) myocardial infarction without ST segment elevation, (3) chronic stable angina, and (4) unstable angina.
Data were collected from the inpatient cardiology department at St. John's Medical college Hospital Bangalore. Investigator visited the patients admitted to the coronary care unit on a daily basis. Consultants from the Cardiology department confirmed the diagnosis of IHD with the aid of ECG and cardiac enzyme studies. Patients fulfilling the inclusion criteria were selected and were explained about the nature of the study, and then informed consent was taken from all the patients. Selected patients were interviewed on third or fourth day of the admission instead of the day itself, in view of possible unstable medical condition interfering with the interview procedure. All instruments were administered in a single session of one and a half to two hours duration approximately. Patients were first administered the Mini Mental Status Examination (MMSE) or Hindi Mental Status Examination (HMSE) wherever applicable. Then the clinical proforma, Structured Clinical Interview for DSM-IV Axis I Diagnosis (SCID-I), and Health related quality of scale (EQ-5D) were administered. The diagnosis (ICD-10 and DSM-IV), the proposed medication and the role of counseling were discussed with the cardiologists and the clients having a psychiatric morbidity.
| Results|| |
The sample consisted of predominantly males (n=101, 77.7%) compared to females (n=29, 22.3%). Age ranged from 26 to 80 years. Seventy-two patients were in the range of 46-60 years, 38 below age 45, and 20 patients were above 60 years. The religious break up found predominance of Hindus (70.8%), followed by Christians (23.1%) and Muslims (6.2%). Majority of the patients were married (n=109, 83.8%).4.6% were unmarried and 11.5% lost their spouses. 93 (71.6%) patients were from urban background whereas 28.4% represented rural areas. The family structure revealed clients belonging to nuclear family represented 73.8% while 26.2% were from non nuclear family. Most of the patients had formal education (49.2% were with school education and 43.8% had college education). 6.9% were illiterate. Twenty-nine (22.3%) were unemployed. Employment break up revealed professionals (11.5%), business (16.2%), farmers (13.1%), skilled workers (13.1%), and clerks (6.9%). Retired ones and house wives comprised 16.9%. Majority of the patients (n=87, 66.9%) reported financial problems and almost a similar number of patients (n=84, 64.6%) reported decreased efficiency in work capacity in the previous 1 year.
Clinical details and illness related information
Mean age at onset of IHD was 50.96 with a range of 49 (min =26, max 75) and SD was 10.03. Mean age of the patient in this study was 56.81, range 54 (26-80) SD was 10.72.
Number of episodes of MI
Forty-one (31.5%) patients reported history of previous episodes in the past. In these 41 patients, the majority (n=24, 58.5%) reported a single episode of MI in the past, 11 (26.8%) reported two episodes and 6 patients (14.6%) reported more than two episodes.
Presence of diabetes, hypertension, dyslipidemia
Majority of the patients (n=72, 55.4%) had hypertension along with IHD, almost a similar number of patients (n=68, 52.3%) were with Diabetes Mellitus. Number of patients with co-morbid dyslipidemia was even higher than diabetes and hypertension (n=85, 65.4%).
Other clinical details
Ten patients (7.7%) had invasive procedures like CABG and angioplasty in the past.
The diagnostic categories included ST elevated MI (STEMI) (53.8%), non ST elevated MI (NSTEMI) (19.2%), unstable angina (UA) (26.2%), and chronic stable angina (CSA) (one patient).
On general examination, 55 (42.3%) patients had some form of abnormal physical signs like pallor, edema, raised JVP etc., and on systemic examination 59 (45.4%) patients had abnormal cardio vascular signs like S3, S4, murmur, crepitations etc., Majority of patients (n=84, 64.6%) had an ejection fraction more than 41%.
Alcohol and smoking
About 45.4% reported past or present alcohol use of which 19 (32.2%) were current users, 14 (23.7%) were ex-users and 20 (33.8%) patients fulfilled a diagnosis of alcohol dependence syndrome (ADS). 54.6% reported no alcohol use.
Sixty (46.9%) patients had history of smoking. Among these, 43 (70.5%) were current smokers and 18 (29.5%) patients had past smoking history.
Psychiatric symptoms, either depressive or anxiety were present in most of the patients (n=124, 95.4%). Depressive symptoms were noticed in 111 (85.4%) patients whereas anxiety symptoms were present in 66 (50.8%). With regard to psychiatric diagnosis major depressive disorder was present in 45 (34.6%) patients. 31 (23.8%) patients were qualified for a diagnosis of depressive disorder due to a general medical condition (IHD). Anxiety disorder was diagnosed in 48 (36.9%). Sixteen patients reported both anxiety disorder and depressive disorder. None of patients reported psychotic disorder. Thirty-nine (30.0%) patients had the presence of dysthymia, of which 26 patients had double depression. Comorbid psychiatric disorders included panic disorder (3.1%), generalized anxiety disorder (3.8%), and adjustment disorder (7.7%) [Figure 1].
For the purpose of further analysis, patients were classified into four groups: (1) Major Depressive disorder (MDD) (2) anxiety disorder due to medical condition, (3) those having both anxiety disorder and MDD, (4) those without any psychiatric diagnosis. Further analysis using tests like 't' test and Pearson Chi-Square, significant association was observed in the following variables such as (i) sex of the patient (ii) educational status, (iii) the presence of diabetes mellitus, (iv) and the presence of abnormal physical signs.
Health related quality of life
EURO QOL-5D measures the quality of life across five dimensions. They are mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Usual activities include house work, study, family, or leisure time activities and work. Patients who reported some problems form the majority group in all domains except for anxiety or depression domain [Table 1].
Thirty-one (23.8%) patients reported that they were unable to perform usual activities and 19 (14.6%) patients reported no problem in activity. Majority (n=80, 61.5%) reported some difficulties. Only 8 (10%) patients reported impairment in mobility and 29 (22.3%) reported no impairment in mobility [Table 2].
Number of patients with good QOL were more (n=45, 34.6%) in self care domain. 21 (16.2%) patients reported poor QOL in the same.
Higher rate of poor QOL was noted in the anxiety/depression domain (n=65, 50%). Pain and discomfort domain revealed high percentage of good quality of life (n=62, 47.7%).
The Hr QOL mean score was 9.654 with a range of nine having a maximum score of 15 and minimum score of five. Summary statistics for individual items are shown in [Table 2]. Chi-Square results from cross tabulation between Hr QOL items with psychiatric morbidity as well as socio-demographic and illness related variables have shown significant association for following items (i) activity, (ii) anxiety/depression, (iii) mobility, (iv) and self care. One-way ANOVA was used for comparison of mean EQ 5 total score between the groups with psychiatric morbidity. In post hoc test (multiple comparisons) for Hr QOL total ratings across different groups the following items have shown significant association (i) group with depression versus no psychiatric morbidity group, (ii) group with only anxiety versus group having both anxiety and depression, (iii) group with both anxiety and depression versus none group. Post hoc test results for Hr QOL total ratings for depression due to IHD versus MDD groups revealed significant association for two groups: MDD versus depression due to general medical condition and MDD versus none group. Comparison of mean Hr QOL EQ five total score with different variables has shown following items as significant (i) age, (ii) sex, (iii) marital status, (iv) family type, (v) psychiatric morbidity (depressive episode, depression due to general medical condition and anxiety disorder), (vi) diabetes mellitus, (vii) abnormal physical, and cardiac signs, (viii) treatment for IHD.
| Discussion|| |
The focus on psychiatric aspects of medical disease has been on the increase in the past few decades. The concept of consultation liaison psychiatry is gaining ground as more research is being done in this area. Psychosocial management is becoming a part of treatment of chronic medical illness. More awareness is being created among physicians, and evidence of effective treatment for psychiatric disorders is reducing the negative attitudes toward psychiatric disorders. This study was undertaken to systematically examine the psychiatric aspects of IHD focusing on the prevalence of psychiatric symptoms and disorders and its relation to health related to quality of life.
MMSE is a simple, brief scale with high sensitivity and reliability  also is used for excluding patients with cognitive impairment.
To assess psychiatric morbidity, Structured Clinical interview for DSM-IV Axis I diagnosis (SCID-I) was used.  It is a semi structured diagnostic interview and all available information including hospital records, informants, and patient information was used to rate the SCID-I. The superior quality of SCID as a tool for research on mental disorders ensured a uniform and standard assessment in all subjects.
Though there are generic as well as disease specific instrument available to assess QOL, EQ-5D was used in this study.  This is a simple scale, short, and easy to administer, which basically measures health related QOL across five dimensions. It has been used in a variety of medical conditions. This instrument has minimum possible confounding influence on socio cultural differences. This instrument has proved as a valid general Hr QOL measurement post-MI.  The limitation with disease specific questionnaires like Mac new Heart Disease Quality of Life instrument is that many items are not applicable to Indian population. 
Majority of the sample were males (n =101, 77.7%). This is expected since male gender is an established risk factor for IHD. One earlier study has reported that peak period for IHD is: (a) between 51-60 years (b) males are affected more than females (c) hypertension and diabetes account for about 40% of all cases (d) heavy smoking is responsible etiologically in a good number of cases.  Our findings are also in conformity with these observations. In our study more than half of the patients (55.4%) were in the age group of 45-60 years. Diabetes mellitus was present in a similar proportion of patients (52.3%). Sixty-one (46.9%) patients were reported nicotine use. Majority of our sample had the presence of hypertension and dyslipidemia (55.4 and 65.4%, respectively). Though family history is a risk factor for IHD in our sample only a minority had a family history of IHD (n=31, 23.8%). , Patients who had abnormal physical or cardiac signs were less than half of the sample. This is expected because of the fact that at the time of interview, patients were largely stable and received good medical support. The same fact is reflected in the finding that majority had normal ejection fraction, >41% (n=84, 64.6%).
Prevalence of psychiatric comorbidity associated with IHD varies from 17 to 45%. A high proportion of patients reported psychiatric symptoms in our study either depression or anxiety (n=124, 95.4%). Two studies on prevalence of psychiatric morbidity reported rates of 35%, 44.8%. , Though widely disputed, low educational status was reported as significantly associated with psychiatric morbidity in IHD. , In our study, we found the same association, thus making a strong point that low educational status is indeed associated with psychiatric morbidity. Studies, which looked into the influence of marital status contributing to the psychosocial morbidity, reported conflicting results on the association. , This has been confirmed in another study.  In our study, we also did not find an association between marital status and psychiatric morbidity. We found that female sex of the patient and the presences of diabetes mellitus were associated with psychiatric morbidity in a significant manner. Diabetes is a known medical illness producing marked psychiatric morbidity, especially affective disorders. So the finding was in accordance with current research evidence with regard to diabetes and psychiatric morbidity.
Quality of life (QOL) has been defined as "the subjective satisfaction expressed or experienced by an individual in his physical, mental, and social situations.  Various measures both generic as well as disease specific have been used to assess QOL. The performance of basic social roles and activities of daily living is often used as a standard for the impact of disease on quality of life. The dimensions of quality of life that were analyzed included the following: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Since weighted scores are not available for Indian population, we have taken the grand total and subtotal for analysis. When the frequency tabulations were done, we found that maximum number of patients with good quality of life were in the domain of pain/discomfort domain. Reflecting the same finding in Chi-square cross tabulation with psychiatric morbidity the domain of pain/discomfort did not show any significant association. Patients with poor quality of life were seen maximum in the domain of anxiety/depression. We divided psychiatric morbidity into four groups, namely major depressive episode, anxiety due to general medical condition, both depression and anxiety disorder and a group with none. These groups were compared with Health related QOL mean total score, we found that group with major depression, group with anxiety due to general medical condition, and group with both comorbidity have shown significant association with QOL total score compared to group having no psychiatric morbidity. This finding is comparable to the previous studies that had shown depression and anxiety at entry point as a powerful predictor of QOL among survivors of myocardial infarction. ,,
When major depressive episode was compared with depression due to general medical condition on HrQOL total mean score, major depression was found to be more significant. 't' test results for Hr QOL EQ 5 D total score with various demographic and clinical variables have shown results in the expected lines. Age has been reported as a significant variable in earlier QOL studies.  These studies had reported poor quality of life as age increases. Like the previous studies, we also found that advanced age is a predictor of poor quality of life. Male patients were found to have better quality of life compared to female patients. People with nuclear family had good quality of life compared with patients from non-nuclear families. Among psychiatric morbidity depression had the maximum significance with regards to poor quality of life compared with depression due to general medical condition or anxiety. Abnormal physical signs or other medical illnesses with an established role in the pathogenesis of psychiatric morbidity like diabetes were proved as significant with regard to QOL in this study.
These findings are preliminary and need more studies before any definite conclusion can be drawn. Lacks of comparable studies also makes these findings interesting and support the case for further studies.
Standardized instruments with proven reliability and validity were used for assessments. To improve the quality of assessments, we took adequate precautions to avoid any possible interference due to delirium and other serious medical complications. All the variables on which data were collected were truly reflective of the problem and have got practical implications.
In view of the paucity of studies in our country concerning psychiatric morbidity in IHD, our attempts to have a close look at psychiatric morbidity and quality of life in a reasonable sample of IHD patients may serve a platform for further research.
Limitations of the study and suggestions
The design was cross sectional but a prospective study would have given a better idea about development and course of psychiatric symptoms and disorders. A large sample based prospective study with a control group is needed to overcome the limitation of cross sectional studies. Axis II problems were left out from the purview of our assessment, Axis II issues have important role in quality of life as well as psychiatric morbidity. A study looking at both Axis I and Axis II comorbidity patterns would be helpful to understand the problem comprehensively. A control group would have enabled us to compare the rates with age and sex matched populations.
| Acknowledgment|| |
Thank to Dr. Prakash Appaya and Dr. E. Mohandas for their valuable contributions to this work.
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Department of Psychiatry, Amala Institute of Medical Sciences, Thrissur, Kerala
Source of Support: None, Conflict of Interest: None
[Table 1], [Table 2]