The Role of Lifestyle in Development of Coronary Heart Disease

This chapter focuses on the study designed to assess the role of lifestyle in the development of coronary heart disease (CHD). The data were analyzed to compare the patients of CHD with matched normal. Lifestyle is defined as the general behaviour pattern of an individual including health behaviour, job involvement and work style, social interactions, intimacy, locus of control and values. For this purpose the matching of patients was carried out on one to one basis and on the parameters of the age, education, family size and socioeconomic status. Total sample size was 162. To measure lifestyle, a structured interview schedule was prepared which included questions on the subparts, viz. health behaviour pattern, job involvement and work style, social interactions, intimacy, locus of control, values. The coding of the responses was quantified. The higher is the scores more is the risky lifestyle whereas lower scores indicate the healthy lifestyle. Qualitative and quantitative analysis were carried out.


Introduction
Cardiovascular disease is reported to be the leading cause of death in world. In 1998, 12.4 million people died of heart attack and stroke. Of these 78% were in low and middle income countries. The high income countries had lower death rates because of better preventive and treatment program [1]. Though, several clinical and biochemical risk factors have been identified, the role of psychological factors are also gaining importance during the past few decades. Several risk factors have been identified to be associated with coronary heart disease (CHD) which include causative risk factors (hypertension, hyperlipidemia and diabetes), conditional risk factors (triglycerides and lipoprotein), and predisposing risk factors (obesity, physical activity, sex, family history, socioeconomic factors, insulin resistance and psychological factors) [2]. Evidence of various studies has shown a strong association in psychological stress and CHD. Cardiovascular disorders pose a major health problem for industrialized societies in terms of excess of morbidity and mortality. It is evident from the review of literature that there is a strong relationship between coronary heart disease and some psychological factors. Psychological variables like stress, personality, anxiety and lifestyle are contributing along with high blood pressure, obesity; lack of exercise,

Status in India
In India, in the past five decades, rates of coronary disease among urban populations have risen from 4 to 11% and four Indians die every minute due to heart disease. In India, 50% of heart patients are under 45 years of age [11]. CHD is emerging as a major cause of death in India. It has been projected that 15 years from now India would have highest CHD deaths compared to any other country [12]. ICMR and WHO have predicted that cardiovascular diseases would be the most important cause of mortality and morbidity in India by the year 2015 [13]. Data from Christian Medical College, Vellore and All India Institute of Medical Sciences, New Delhi, over a period of 30 years showed a decline in admission for rheumatic heart disease (RHD) and increase in admission for CHD [14]. A comparative study in Singapore on Indians and Chinese, revealed stronger cardiovascular reactivity to stress among Indians than compared to Chinese men [15]. Chronic anxiety and tension have been suggested as factors in the development of CHD. There is strong evidence supporting prognostic associations with social isolation and low perceived emotional support and unhealthy lifestyle behaviors in the development of CHD [16]. In India, it has been observed that there is age related increase in CHD. The incidence of myocardial infarction (MI) was more common in urban India than rural areas of India [17]. Studies in India have shown that heart attacks in India occur 10 years earlier than in West. Hence it is needed to undertake well designed prospective studies for evaluation of CHD in relation to psychological factors [18]. According to Theorell et al. [19], cases of CHD may increase from about 2.9 crore in 2000 to as many as 6.4 crore in 2015.The prevalence rates among younger adults (age group of 40 years and above) are also likely to increase. Prevalence rates among women will keep pace with those of men across all age groups. Data also suggest that prevalence rates of CHD in rural populations will remain lower than that of urban population [17].
In brief the rationale of the study is the limited research available in this area related to psychological factors in India. This study was carried on matched subjects to contribute to this significant domain of research.
Lifestyle is one of the major factors which have shown a strong association with CHD [5]. Lifestyle is based on subjective perception. The behaviour pattern of an individual as expressed by his motives, his manners of coping and other factors including values, social and family satisfaction, job satisfaction and work style are called lifestyle. In the present study lifestyle is measured on heath and behaviour pattern, job involvement, social interactions, intimacy, locus of control and values. Research work has been done linking lifestyle, personality and coronary heart disease. It shows that Type A behaviour pattern (TABP) promotes a lifestyle which facilitates exposure to range of social, personal and occupational stresses which emerges into a coronary heart disease. Wright's identified five separate paths to coronary artery disease that are inherited risk based on family history, risks that accrue from personal lifestyle choices such as overeating and lack of exercise, anger directed inward, anger directed outward that is combined with a sense of time urgency and chronic activation and the traditional Type A pattern identified by Rosenman and Friedman. Regular physical activity in the context of work, recreation or an exercise training programme is associated with a marked reduction in heart disease related deaths in patients. Exercise has positive effects on the cardiovascular system that reduce risk for coronary artery disease and myocardial ischemia. Exercise tends to reduce heart rate, it improves the efficiency of the heart and it reduces blood pressure. It improves efficiency in the respiratory system so that oxygenation of blood and supply of oxygen to heart is better. Exercise reduces weight and there is a beneficial effect on cholesterol, triglycerides and ratio of HDLs to LDLs. The National High Blood Pressure Education Program recommended four changes in lifestyle to help, prevent or manage hypertension, since hypertension is a major modifiable risk factor for CHD. These are weight control, reduced salt intake, increased exercise and moderate alcohol consumption. Diet has a direct and important role in heart disease that goes beyond cholesterol. A diet high in saturated fat increases the risk of heart disease and stroke. Gender linked risk cannot be changed but high blood pressure, elevated cholesterol and smoking can be significantly reduced by life changes. Simple adjustments to diet and exercise have positive effects on both cholesterol and blood pressure. Tobacco use, whether it is smoking or chewing tobacco, increases risk of cardiovascular disease. Passive smoking is also risk factor for CHD. The relationship between smoking and risk for CHD is simple and direct. Incidence of heart attacks and sudden cardiac deaths is directly related to the number of cigarettes smoked on a regular basis. Cigarette smoking is the most preventable cause of coronary heart disease. The Framingham data show that men who smoke have up to 10 times the likelihood of sudden death compared to nonsmoker. Smoking interferes with the oxygen carrying capacity of blood, it reduces bioelectrical control and finally smoking increases the tendency to platelet aggregation and clot formation. Clots increase the potential for thrombosis and fatal coronary. Russek and Zohman [8] observed emotional strain associated with job responsibility in young coronary patients. There is a positive association between job dissatisfaction and CHD. Karasek's group in Sweden [18] explored the relationship of the kinds of work stresses that may be associated with cardiac pathology. They had given a model which links high work demands with an inability to make decisions. Theorell's prospective study of 6500 middle aged males in Swedish construction industry found dissatisfaction with domestic and working life was predictive of suffering a myocardial infarction during subsequent 2 years. In a study of London transport bus drivers and conductors, results showed that bus drivers had significantly higher incidence of heart disease than bus conductors because of more responsible and stressful nature of their work. The Framingham study showed that men undergo in frequent work promotions sustained an increased chance of developing CHD. A supportive social network and having community ties promote emotional and physical wellbeing. Some studies validate positive relationship between social support and CHD mortality. Studies on marital status have repeatedly shown that the single widowed or divorced have higher CHD mortality rates compared to their counter parts. It was also found that interpersonal relationship and marital dissatisfaction or disagreements were risk factors for CHD.
The association between values and attitudes towards life was studied in cross cultural context in Japanese young men.
It was found that Japanese who maintain their traditional way of life, values and language after their emigration to US, do not have increased rate of CHD. In study of Japanese-American males found that those with the lowest level of social affiliation had double the risk of developing CHD. The rate of CHD mortality increases due to smoking, alcohol and foods rich in fats, less exercise, lack of control over one's working environment, reduced levels of social support, the cumulative life cycle experience of belonging to a social class or nation undergoing rapid urbanization and industrialization.
The main objective of this research was to study the role of lifestyle in development of CHD and hypothesis formulated was patients of coronary heart disease (CHD) would score higher on subscales of lifestyle as compared to matched non-CHD individuals.
This being a study on stress, anxiety, type A behaviour pattern and lifestyle variable of the patients of coronary heart disease (CHD) and their matched normal patients for the present study were selected from cardiac care unit (CCU) of hospitals from Pune city. During the survey for CHD patients 10:1 ratio of male to female was observed. As, there is a physiological cause that men having a greater risk of heart disease than women do, because, the higher levels of high density lipoprotein (HDL) cholesterol, which helps to slough off the more lethal low density lipoprotein (LDL), these higher HDL levels appear to be linked to premenopausal women's level of estrogen. Estrogen diminishes sympathetic nervous system arousal, which may add to protective effect against heart disease seen in women. So in the present study only male CHD patients were selected. Out of 121 male CHD patients admitted in CCU's of various hospitals in Pune, 81 CHD male patients agreed to participate in the present study. In the present study selection of 81 matched normal was done by keeping the patients in view. The patients and normals were matched, one to one on the variables of age, education, occupation, family type and socioeconomic status. These 81 male CHD patients met the inclusionary criteria, which were as follows: Age: 30-60 years; education: minimum S.S.C. passed; occupation: employed; family type: nuclear family is staying with wife and children, and joint family is staying with wife, children and parent; socioeconomic status: minimum income Rs 10,000 per annum. The normals were selected after the medical checkup by the physicians who labeled them as normal as they were not suffering from any disease.
Following tools and measures we used for data collection. Personal data sheet: A personal data sheet comprising 14 items was prepared and was required to be filled in by the patients and normal before the actual administration of psychological scales. The items were designed to get the information about age, education, occupation, family type and socioeconomic status.
Interview schedule: To measure lifestyle in CHD patients and normal individuals, structured interview schedule was prepared on the basis of operational definition of lifestyle. Interview schedule includes four subparts in which questions are formulated beforehand and asked in a set order in a specified manner. The description of interview schedule is given in Appendix A.
Description of the sub-dimensions is given below.

Procedure
A special permission was sought to collect the data of CHD male patients from cardiac care unit (CCU) of Pune city which includes Ruby Hall Clinic, Jahangir Hospital, DinDayal Heart Institute, Dinanath Mangeshkar Hospital, Joshi Hospital, Kashibai Navale Hospital and Sasoon Hospital.
On the initial contact, after noting down residential address of the patients, a formal permission was sought to see them at home after discharge from CCU within 10 days. Special visits were made to see the CHD patients from Khadki, Dapodi, Aund, Pimpari, Chinchwad, Vishrantwadi and Katraj in Pune city to interview and complete the psychological measures. After establishing proper rapport and explaining the objectives and purpose of the study the patients of CHD co-operated whole heartedly. All the scales and interview schedule used for this study were given individually to each patient at his residence. All the patients were assured that information given by them would be kept confidential and utilized solely for research purpose only. They were also instructed to ask for clarification of any doubtful item, specific instructions for each scale were printed at the beginning of the scale. No time limit was imposed for the completion of the scales.
Immediately within a week the sample of Non-CHD individuals were selected after medical checkup by the physician who labeled them as normal as they were not suffering from any disease. The patients and Non-CHD individuals were matched one to one on each of the variables of age, education, occupation, family type and socioeconomic status. A matched normal was assessed by psychological tests and was interviewed personally by visiting their houses. Initially it was proposed to take 75 numbers of data for both CHD patients and matched normal. But effective rapport and co-operation by CHD patients and matched non-CHD individuals the sample size was increased to 85, out of which four were rejected because the questionnaires were incomplete. In the present study the no of CHD patients were 81 and matched Non-CHD individuals were 81. So the total sample size was 162.

Analysis of data
Data were analyzed with the help of statistical techniques like descriptive statistics, and 't' test. However, a few cases were explained to understand the qualitative analysis.

Qualitative analysis
Analysis of personal data sheet was carried out. A personal data sheet comprising 14 items was prepared. The information in the personal data sheet was sought in order to match patients of CHD and non-CHD individuals on age, education, type of family and socioeconomic status.  Table 1 and Figure 1 show age group wise sample distribution. Fifty percent respondents belonged to the age group of 40-50 years. Similarly 14.8% belonged to 30-40 years of age, and 34.6% belonged to 50-60 years of age. Table 2 and Figure 2 show that there are 53% participants who are having PG education. There are 35.8% participants who were having graduation and remaining 11.2% participants who had completed H.S.C or diploma. Table 3 and Figure 3 show that 71.6% participants belonged to the nuclear family. Similarly 28.4% belonged to joint family. Table 4 and Figure 4 show socioeconomic status wise sample distribution. 4.9% respondents belonged to the 1,00,000-3,00,000 annual income group. 38.4% respondents belonged to the 3,00,000-6,00,000 annual income group. 35.8% respondents belonged to the 6,00,000-9,00,000 annual income group and similarly 20.9% respondents belonged to 9,00,000 and above annual income group.

Demographic characteristics of the sample
Two case studies have been given to understand experiences of CHD male patients in greater detail. As mentioned earlier, a lifestyle was referred as a general behaviour pattern of an individual which includes health behaviour pattern, job involvement and work style, social interactions, intimacy, locus of control and values. Health behaviour pattern is a set of habits includes sleeping habits, dietary habits, daily exercise, smoking habit and physical and mental health.

Case study 1
A CHD patient of 37 years old working as a senior manager from last 2 years. He represents a nuclear family having a wife and a daughter. He had no family history of any disease. He is non-vegetarian and most of the time had outside eatables. He is a chain smoker. He is workaholic, carrier and money oriented and no time to spend with his family. A matched non-CHD individual also non vegetarian but most of time take his meal with family and rarely had outside eatables. He does not have any bad habit like smoking, chewing tobacco, etc. He had perfect compartment of work place and for family. He spends his weekends with picnic, get-together with friends, His priority to people and money.

Case study 2
A CHD patient of 45 years working as a senior lecturer from last 14 years. He represents a nuclear family of a wife and two daughters. He had no family history of any disease. He is vegetarian, not spend a single minute for exercise. He always chews tobacco. He is very competitive and always feels unhappy about his life and feels unlucky. He is religious and always depends on god. "I am very unlucky." "Asel debauch manat tar milel" such type of dialog often with him. He does not spend money, always worried about dowry and marriage of daughters. A matched Non-CHD individual is vegetarian as well as non-vegetarian. He daily takes a walk for half an hour. He is happy go lucky enjoy all the moments and takes responsibility of his work. The qualitative description of the two representative cases of CHD and non-CHD groups clearly demonstrates the noticeable differences in lifestyle factors. Results have been now discussed quantitatively.

Lifestyle among patients of CHD and matched non-CHD individuals
The results of present study indicate that the mean differences were statistically significant for subscales of lifestyle.
With reference to Table 5, CHD and lifestyle risk factors showed a significant positive association with sleeping habits, dietary habits, exercise and Smoking respectively. It was also appeared that there was a positive link between poor social interactions, poor intimacy, more external locus of control and more money and religious values. So, the hypothesis, "Patients of Coronary Heart Disease (CHD) would score higher on subscales of lifestyle as compared to matched Non-CHD individuals" is accepted.
The results of the present study support the findings of the earlier studies in association with lifestyle and risk of coronary heart disease (CHD). Gupta and Gupta [18] carried out a study on Indian male. In the present study, it was found that lifestyle risk factors like diet, smoking habits plays an important role in development of CHD. Orth-Gomer et al. [20] have demonstrated that low social support and poor social integration predicted incidence of major coronary events. The results revealed that the patients of CHD showed significant differences on locus of control, it indicates that the patients were titled towards external locus of control due to which they experienced the high stress on the other hand the matched non-CHD individuals due to their internal locus of control experienced less amount of stress and remain healthy [21]. The obtained results were discussed in the light of violation of assumption and compared with the results of earlier studies with necessary caution. A positive family history of premature coronary heart disease is recognized as an independent predictor for cardiovascular mortality in the first degree relatives. This will enable public health and behavioral epidemiologists to plan and target appropriate and effective preventive lifestyle   techniques to adults. Therefore, its primary prevention is an important factor. Several studies have shown that primary prevention of coronary heart disease by family life education in the community has better benefits compared to secondary prevention for cardiovascular mortality as well as morbidity. Prevention programmers should have a multi-level focus, including individual, family and other social institutions. It is also important to identify subgroups for intervention, so that necessary steps at earlier level itself can be taken for the prevention of lifestyle diseases like coronary heart disease.

Limitations
CHD is a life time disorder; it is difficult to detect the sufferer as this illness does not reveal any overt causal symptoms. Moreover to get the authentic data, it was highly essential to consult the medical practitioners or cardiologists. Therefore, the researcher had to fully depend upon on the data which was available only in hospitals and clinics.
1. As mentioned in literature, the incidence of CHD is a global health problem which is given only medical attention, the psychological part of it is almost neglected. Though there are many psychological dimensions to it, only lifestyle has been studied in the present research, the other dimensions also needed to be studied.
2. The research is based on the data from Pune only.
3. This study was limited to male population only.

Implications
Healthy behaviour patterns like sufficient sleep, healthy diet, regular exercise, more social interactions, intimacy, and internal locus of control have beneficial effects among the non-CHD individuals. It is therefore reasonable to promote such a healthy lifestyle to the patients of CHD.  Table 5.