Serial epidemiological surveys in an urban Indian population demonstrate increasing coronary risk factors among the lower socioeconomic strata.

OBJECTIVE: To determine trends of coronary risk factors in an Indian urban population and their association with educational level as marker of socioeconomic status. METHODS: Two successive coronary risk factor surveys were performed in randomly selected individuals. In the first study (in 1995) 2212 subjects (1415 men, 797 women) and in the second (in 2002) 1123 subjects (550 men, 573 women) were studied. Details of smoking, physical activity, hypertension, diabetes, coronary heart disease, body-mass index, waist-hip ratio, blood pressure and electrocardiography were evaluated. Fasting blood was examined for lipid levels in 297 (199 men, 98 women) in the first and in 1082 (532 men, 550 women) in the second study. Educational status was classified into Group 0: no formal education, Group I: 1-10 years, Group II: 11-15 years, and Group III: > 16 years. Current definitions were used for risk factors in both the studies. RESULTS: Prevalence of coronary risk factors, adjusted for age and educational status, in the first and second study in men was smoking/tobacco in 38.7 vs. 40.5%, leisure time physical inactivity in 70.8 vs. 66.1%, hypertension (> or = 140 and/or 90 mm Hg) in 29.5 vs. 33.7%, diabetes history in 1.1 vs. 7.8%, obesity (body-mass index > or = 25 Kg/m2) in 20.7 vs. 33.0%, and truncal obesity (waist:hip > 0.9) in 54.7 vs. 54.4%. In women, tobacco use was in 18.7 vs. 20.5%, leisure time physical inactivity in 72.4 vs. 75.3%, hypertension in 36.9 vs. 33.7%, diabetes history in 1.0 vs. 7.3%, obesity in 19.9 vs. 39.4%, and truncal obesity (waist:hip > 0.8) in 70.1 vs. 69.2%. In men, high total cholesterol > or = 200 mg/dl was in 24.6 vs. 37.4%, high LDL cholesterol > or = 130 mg/dl in 22.1 vs. 37.0%, high triglycerides > or = 150 mg/dl in 26.6 vs. 30.6% and low HDL cholesterol < 40 mg/dl in 43.2 vs. 54.9%; while in women these were in 22.5 vs. 43.1%, 28.6 vs. 45.1%, 28.6 vs. 28.7% and 45.9 vs. 54.2% respectively. In the second study there was a significant increase in diabetes, obesity, hypertension (men), total- and LDL cholesterol and triglycerides and decrease in HDL cholesterol (p < 0.05). In the first study with increasing educational status a significant increase of obesity, total cholesterol, LDL cholesterol and triglycerides and decrease in smoking was observed. In the second study increasing education was associated with decrease in smoking, leisure-time physical inactivity, total and LDL cholesterol, and triglycerides and increase in obesity, truncal obesity and hypertension (Least-squares regression p < 0.05). Increase in smoking, diabetes and dyslipidaemias was greater in the less educated groups. CONCLUSIONS: Significant increase in coronary risk factors--obesity, diabetes, total-, LDL-, and low HDL cholesterol, and triglycerides is seen in this urban Indian population over a seven year period. Smoking, diabetes and dyslipidaemias increased more in low educational status groups.

Influence of total cholesterol levels on long-term mortality in coronary heart disease: a reappraisal.

To examine the prognostic significance of total cholesterol levels at baseline in subjects with stable coronary heart disease, 605 patients with stable coronary heart disease were enrolled; 45 of these did not meet inclusion criteria, 41 were lost to follow-up and 40 opted for coronary bypass surgery. Data of the remaining 479 (389 males, 90 females) were analysed. There were 102 males in group I (cholesterol < 200 mg/dL), 187 in group II (cholesterol 200-239 mg/dL), and 100 in group III (cholesterol > or = 240 mg/dL) and 49 females in group I and 41 in group II. The groups were evenly matched for age and numbers with stable angina or survivors of myocardial infarction. Proportion of smokers, hypertensives, diabetics or obese was also similar (p > 0.05). Mean follow-up in years in men was 6.82 +/- 3.15 in group I, 6.37 +/- 3.11 in group II and 6.81 +/- 2.84 in group III while in women it was 6.95 +/- 2.84 in group I and 7.03 +/- 2.58 years in group II and was not different in various groups (p > 0.05). The overall cardiovascular mortality in various groups in men was 20.6 percent in group I, 28.9 percent in group II and 23.0 percent in group III and in women it was 14.3 percent in group I and 22.0 percent in group II. The crude mortality rate was 2.51 percent per year in males and 1.77 percent per year in females. Actuarial survival at end of seven years in males was 0.76 +/- 0.05 in group I, 0.67 +/- 0.04 in group II, and 0.67 +/- 0.05 in group III and in females it was 0.85 +/- 0.05 in group I and 0.73 +/- 0.09 in group II. The cumulative hazard rates per 1000 person- year follow-up in group I, II and III in males were, at age less than 50 years: 5.4 +/- 5, 19.8 +/- 7, 17.4 +/- 8; at 50-59 years: 23.8 +/- 11, 38.5 +/- 9, 39.8 +/- 13; and at 60 years and over: 76.9 +/- 20, 112.6 +/- 20, 108.2 +/- 28, respectively (p < 0.001 on comparison of group I with groups II and III). In females the trends were not significant. Total cholesterol levels at baseline predict long-term cardiovascular mortality in men with stable coronary heart disease.

Smoking and alcohol intake in a rural Indian population and correlation with hypertension and coronary heart disease prevalence.

3148 persons (1982 males and 1166 females) aged more than 20 years in a cluster of three villages were examined. The overall prevalence of smoking was 51% in males (n = 1006) and 5% in females (n = 54). Among male smokers there were 26% light smokers (< or = 5 bidis/day), 51% moderate smokers (6-20/day) and 17% heavy smokers (> 20 day) and in females there were 54% light smokers, 41% moderate smokers and 5% heavy smokers. Smokers were less educated and had higher prevalence of work-related physical activity and alcohol intake. There was a higher prevalence of hypertension and of ECG Q-waves in male smokers. Regular alcohol intake was seen in 19% males (n = 377) and in 2% females (n = 26). Among males there were 43% light drinkers (< or = 28 gm ethanol/day), 32% moderate drinkers (28-56 gm ethanol/day) and 5% heavy drinkers (> 56 gm ethanol/day). Although this group had a higher prevalence of hypertension there was an insignificant difference in CHD prevalence and a significantly lower prevalence of ECG Q-waves. Subgroup analysis has also been performed taking non-smoker-non-alcohol consuming group as controls. It was found that group which comprised of smokers-non-alcohol consumers had a significantly higher prevalence of hypertension and of ECG Q-waves. Alcohol intake-smoker group had a significantly higher prevalence of hypertension. The habits of smoking and alcohol consumption are widely prevalent among males in this rural community. Smoking and alcohol-intake, both individually and collectively, are related to higher prevalence of hypertension as well as CHD. While the prevalence of hypertension is more among the alcohol consumers, smokers have a higher prevalence of CHD.

Coronary heart disease and coronary risk factor prevalence in rural Rajasthan.

To determine the prevalence of coronary risk factors and coronary heart disease (CHD) in rural Rajasthan, 1150 randomly selected individuals in a cluster of villages in central Rajasthan have been studied. These included 805 men and 345 women. The prevalence of various coronary risk factors in the whole group were: Smoking 488 (42.4%); Diabetes (history): 5(0.4%); Alcohol intake: 146 (12.7%); Sedentary lifestyle: 797 (69.3%); Stressful life events: 48 (4.2%); Hypertension (BP > or = 140/90) 152 (13.2%); obesity (BMI > or = 27 Kg/M2): 194 (10.9%); and Truncal obesity (waist:hip > or = 0.93): 20.8%. The overall prevalence of CHD was 46.1/1000. Patients with CHD had a higher prevalence of male sex (67.9 vs 51.5%); educated persons (30.2 vs 28.8%); businessmen (13.2 vs 10.2%); smoking (47.2 vs 40.5%); sedentary lifestyle (75.5 vs 62.3%); stressful life events (7.5 vs 4.8%); and hypertension (26.4 vs 14.8%). On the other hand, persons without CHD had higher prevalence of alcohol intake (10.8 vs 7.5%); regular prayers (23.1 vs 22.6%); physically active lifestyle (37.7 vs 24.5%); obesity (13.6 vs 6.9%), and truncal obesity (21.0 vs 20.0%). The following risk factors emerged significant on statistical analysis (Odds ratio, 95% confidence intervals): male sex (1.99, 1.04 to 3.7); hypertension (2.04, 1.01 to 4.09); male smokers (1.80, 1.28 to 4.09); and sedentary lifestyle (1.86, 1.01 to 3.59). This study shows a low prevalence of CHD in rural population which is however more than previously reported studies from India.

Prognostic significance of radiographic cardiomegaly in patients with coronary heart disease.

To define the long term prognosis in patients with coronary heart disease (CHD) we have used criteria of radiographic cardiomegaly supplemented by M-mode echocardiography. 74 patients (Group A) with CHD and cardiomegaly were seen from 1980 to 1983 and have been compared to 121 patients (Group B) with normal cardiac size and prior myocardial infarction. Patients in Group A were defined by radiographic cardiomegaly with cardio-thoracic ratio of 0.50 or more. The groups were matched for age, sex and major coronary risk factors like hypertension, total cholesterol levels, smoking and diabetes. The echocardiographic diastolic left ventricular internal dimension of 6.16 +/- 0.34 cm was significantly more in Group A as compared to 4.94 +/- 0.26 cm in Group B (t = 2.03, p < 0.05). Actuarial analysis indicates that mortality or surgical option is significantly higher in patients with cardiomegaly (Logrank test = 59.72, p < 0.001) and the mortality is significantly more during the initial years. Thus, radiographic cardiomegaly indicates a bad prognosis in patients with CHD.

Influence of cessation of smoking on long term mortality in patients with coronary heart disease.

Cessation of smoking in patients with coronary artery disease (CAD) has shown variable results. The long term mortality in patients of coronary heart disease (CHD) who quit smoking following diagnosis of their disease has been variable. We have analysed the long term effects of cessation of smoking on mortality in a cohort of 173 patients with CAD and compared the mortality of this group with 299 nonsmokers and 52 current smokers. The baseline data were identical for major risk factors like age, hypertension, diabetes, cholesterol levels, and congestive heart failure among the three groups (p > 0.1). There were more patients with previous myocardial infarction in past (38.7%) and current smokers (40.4%) than among nonsmokers (25.4%). All patients were followed for a period extending upto 11 years. The mean duration of follow up was 6.81 +/- 2.95 years in non-smokers, 5.98 +/- 2.94 years in exsmokers, and 6.32 +/- 3.44 years in current smokers. Actuarial analysis shows that overall mortality was significantly more among exsmokers than nonsmokers (Logrank test = 3.72, 1p < 0.05). The exsmokers showed similar mortality as current smokers during the first three years of follow up (Logrank test = 1.10, 1p < 0.1); but afterwards the mortality was significantly less in exsmokers than in current smokers (Logrank test = 6.29, 1p < 0.025). However, the overall mortality was lowest in nonsmokers when compared to that of exsmokers and current smokers (Logrank test = 3.92, p < 0.05). The total mortality was 28.1% in nonsmokers, 32.4% in exsmokers, and 46.2% in current smokers. The incidence of sudden death was, however, similar in all the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Induction of myocardial ischaemia by mental stress in coronary heart disease.

To define the importance of mental stress in the genesis of myocardial ischaemia in patients with coronary heart disease, we studied 50 cases in whom ischaemia was provoked by a variety of mental stress tasks: arithmetic calculations, reading aloud and emotionally arousing speech. The haemodynamic responses were compared to those induced by exercise stress tests in 38 of these patients. Thirty four of the 50 patients tested (68%) developed electrocardiographic evidence of ischaemia during mental stress tasks as compared to 29 to 38 patients (76.3%) undergoing treadmill stress test (p > 0.05). The personally relevant emotionally arousing speech task caused more frequent changes as compared to maths and reading tasks (p < 0.01), although reading task provoked more ischaemia than maths task (p < 0.01). The magnitude of ischaemic changes was similar for emotionally arousing speech and treadmill test. On comparison of haemodynamic changes in 38 patients in whom both exercise and speech tasks were performed, it was seen that ischaemic changes occurred at lower heart rates (p < 0.01), lower peak systolic blood pressure (p < 0.01) and a lower double product (p < 0.01) during emotionally arousing speech task than during treadmill stress test.

Long term follow up study of prognostic significance of exercise duration during treadmill stress test in patients with stable coronary heart disease.

Treadmill stress tests provide useful noninvasive prognostic information in patients with coronary heart disease (CHD). The present study has prospectively analysed the long term prognostic value of exercise tolerance as measured by exercise time during treadmill stress test in 335 consecutive patients with stable CHD. 161 had exercise time of 6 minutes or less (mean 4.58 +/- 1.54 minutes) on a modified protocol (Group A) and 174 had exercise time of more than 6 minutes (mean 9.30 +/- 0.74 minutes)(Group B). Both groups were matched for major coronary risk factors (hypertension, smoking, diabetes and cholesterol levels) and type of drug therapy (betablockers, nifedipine, diuretics and aspirin). The patients have been followed up for upto 9 years with a mean of 6.28 +/- 2.99 years (Group A) and 7.87 +/- 1.98 years (Group B). Actuarial analysis shows that the overall survival after dropout due to death or coronary artery bypass surgery was significantly lower in group A [dropouts = 66 (41.0%)] than in Group B [dropouts = 19 (10.9%)] (Logrank test = 39.94, p < 0.001). The mortality was significantly higher in Group A with 58 deaths (36.0%) as compared to Group B with 16 deaths (9.2%) (x2 = 34.98, p < 0.001). The crude death rate was 5.73% per year in Group A as compared to 1.17% per year in Group B. The incidence of sudden deaths was also higher in Group A with 28(17.4%) instances as compared to 5(2.9%) in Group B (x2 = 19.85, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Total cholesterol and mortality in patients with pre-existing coronary artery disease.

BACKGROUND. A positive correlation exists between serum cholesterol levels and cardiovascular mortality. However, the role of serum cholesterol in persons with pre-existing coronary artery disease is not clear. METHODS. A cohort of 524 patients with coronary artery disease was divided into four groups based on the total serum cholesterol values. Group I consisted of 68 patients with cholesterol levels of 200 mg/dl or less; Group II of 116 patients with cholesterol levels between 201 and 220 mg/dl; Group III of 187 patients with levels between 221 and 240 mg/dl and Group IV of 153 patients with cholesterol levels greater than 240 mg/dl. RESULTS. Actuarial survival analysis over an 11-year follow up did not show any overall difference in mortality between these groups (Logrank test statistic = 1.89, p > 0.1). Analysis after adjustment of the data also showed that mortality rates were not different (chi (2) = 4.73, p > 0.05). Hazard function analysis indicated that death rates per thousand person years of follow up were 49.97 +/- 8.4 in Group I, 41.38 +/- 8.4 in Group II, 55.39 +/- 4.4 in Group III and 45.38 +/- 6.4 in Group IV. These were also not statistically significant. Comparison of mortality rates in patients with angina pectoris and past myocardial infarction also showed similar results. CONCLUSION. Total serum cholesterol levels do not influence long term survival in patients with pre-existing coronary artery disease.

Mitral valve prolapse: two dimensional echocardiography reveals a high prevalence in three to twelve year old children.

The prevalence of mitral valve prolapse (MVP) appears to be age related, MVP being commoner in children as compared to adults. This suggests that asymptomatic MVP may be most frequent in children who are very young. In this study, to better define the prevalence of MVP in young children, we used two dimensional echocardiography and prospectively surveyed 213 healthy urban school children between 3 and 12 years of age. MVP was diagnosed when prolapse of mitral leaflet/s was demonstrated by both two-dimensional and M-mode echocardiography at parasternal long-axis views. Overall, MVP was found in 28 of 213 (13.1%) children. MVP was similarly prevalent in all age groups studied (3-5.9 years: 13 of 83 (13.5%); 6-8.9 years: 9 of 71 (11.2%); and 9-12 years: 6 of 31 (16.2%) children; Chi square = 0.57, p greater than 0.5). Univariate analysis showed that the prevalence of MVP was independent of sex, birth weight, resting heart rate and systolic or diastolic blood pressure. A mid systolic murmur was present in 50.6% of the children although it correlated with echocardiographic diagnosis of MVP in only 39.3%. The left ventricular size or wall thickness and mitral EF and DE slopes were similar in children either with or without MVP. Our results indicate that asymptomatic MVP is frequent in children upto 12 years of age. As a diagnostic test of MVP, presence of apical systolic murmur is considerably inferior to echocardiography. No morphological left ventricular correlates were identified in MVP.

Prognostic value of profound ST segment depression during treadmill stress test in coronary heart disease: nine years follow-up study.

To define the prognostic significance of profound ST segment depression (greater than or equal to 3mm) during exercise test, 106 patients of definite coronary heart disease enrolled in a prospective study were followed for up to 9 years. Group A (56 patients) had profound (greater than or equal to 3mm) ST segment depression (3.56 +/- 0.74mm) and Group B (50 patients) had less than 3mm ST segment depression (1.23 +/- 0.35mm, P less than 0.01) during treadmill testing. Group A patients tolerated exercise for a lesser duration in comparison to group B patients (7.22 +/- 3.35 vs. 10.18 + 4.07 minutes, p less than 0.01). At the end of the study, 21 (37.5%) group A patients either died or underwent coronary artery bypass surgery as compared to 8 (16.0%) group B patients (p = 0.02). The difference in the incidence of cardiac deaths between the two groups was not statistically significant (19.6% in group A and 14.0% in group B). However, sudden deaths were significantly more common in group A as compared to group B patients (10 of 11 (90.9%) vs 4 of 7 (57.1%), p = 0.02). These data suggest that profound ST segment depression (greater than 3mm) during treadmill stress test indicates an adverse long term prognosis with the risk in particular, of sudden cardiac death.