https://imcjms.com/public Ibrahim Medical College Journal of Medical Science https://imcjms.com/public/registration/journal_full_text/189 Wed, 19 Apr 2017 15:04:58 +0000 Coronary heart disease (CHD) is a major global health problem with the majority of burden observed increasingly in the developing countries. There has been no estimate of CHD in Bangladesh. This study addresses the prevalence of CHD in a Bangladeshi rural population which also aimed to determine the risk factors related to CHD. Ten villages of Nandail sub-district under Mymensingh were selected purposively. All subjects of age ³20y were considered eligible and were interviewed about family income, family history of T2DM, CHD and HTN. The investigations included height, weight, waist-girth, hip-girth, systolic and diastolic blood pressure (SBP & DBP), fasting blood glucose (FBG), triglycerides (TG), cholesterol (Chol) and high density lipoprotein (HDL). Hemoglobin A1c (HbA1c) and albumin-creatinine ratio (ACR) were also estimated. Finally, electrocardiography (ECG) was undertaken in all participants who had family history of diabetes or hypertension or CHD. Diagnosis of CHD was based on history of angina or changes in ECG or diagnosed by a cardiologist. A total of 6235 subjects were enlisted as eligible (age ³20y) participants. Of them, 4141 (m / f: 1749 / 2392) subjects volunteered for the study. The age-adjusted (20-69y) prevalence of CHD was 1.85 with 95% CI, 1.42 – 2.28. There was no significant difference between men and women. The mean (SD) values of age (p<0.001), SBP (p<0.01), DBP (p<0.05), HbA1c (p<0.05) and ACR (p<0.01) were significantly higher among subjects with CHD than those without; whereas, there were no significant differences in BMI and WHR, TG, Chol and HDL. Logistic regression analysis showed that adjusted for age, sex, social class and obesity, the subjects with higher age (³45y), higher 2hBG (³7.0mmol/l), higher ACR (³17.2) and family history of CHD had significant risk for CHD. The prevalence of CHD is comparable with other Asian population. Family history of CHD and age over 45 years, and who had hyperglycemia and higher ACR were proved to be the independent predictors of CHD. CHD was found to affect participants irrespective of sex, social class, obesity and lipid status. Though the IFG and diabetes groups appeared to have similar biophysical characteristics, only the diabetes group had significant risk for CHD. Further study in a larger sample may be undertaken to confirm the study findings and to explore some unidentified risk factors of CHD. Address for Correspondence: Prof. M Abu Sayeed, Department of Community Medicine, Ibrahim Medical College, 122 Kazi Nazrul Islam Avenue, Shahbag, Dhaka-1000, e-mail: sayeedma@dab-bd.org   Morbidity and mortality from coronary heart disease (CHD) have increased to an epidemic form in the past several decades. A substantial number of reports indicatethattheprevalenceofCHDhasincreasedboth in the developed and in the developing countries.1-4 Recently published reports suggests that CHD is related to social deprivation and low socio-occupational classes.5,6 It is well known that Bangladesh is one of the least developing countries and its per capita GNP is one of the lowest (USD 370) in the world.7 Another important and relevant consideration is that CHD is the leading cause of death among individuals with diabetes.8 The information on CHD and its association with known risk factors in populations with high rates of diabetes is limited and the influence of known duration of diabetes was not observed to be a significant contributor to the cardiovascular risk factors.9 The risk factors were found to be significant in the sub-sample of patients with duration of diabetes even less than 15 years. As regards diabetes, Bangladeshis were found to have a high prevalence of impaired fasting glucose (IFG: 4 – 12%) and type-2 diabetes (T2DM: 4-11%) in the age group equal to or greater than 20 years.10-13 Thus, it appears that the people of Bangladesh are likely to develop CHD for the two obvious reasons – first, due to the exposure of social deprivation; and second, there being a high prevalence of diabetes. However, there has been no known study so far conducted to address this issue. This study was undertaken to determine the prevalence of CHD in a sub-sample of the vast majority of rural Bangladesh and to investigate the risk factors acting upon them. Subjects and Methods The objectives and procedural steps were informed to every individual participant for taking consent. Having consent each individual was requested to attend a nearby investigation spot with at least 12h fast. Each participant was interviewed for clinical history, medication and physical activities, and for women, menstrual history to exclude pregnancy [Figure-1]. Measurements of height, weight, and girth of waist and hip were taken with light clothes and barefooted. Blood pressure was measured after 10min rest. Hemocue Cuvettes were used for measuring capillary fasting blood glucose (FBG). The participants were classified into hyperglycemic and normoglycemic groups based on FBG cut-off at 5.6 mmol/l. All the subjects with hyperglycemia (³5.6mmol/l) were considered eligible for further investigations like oral glucose tolerance test (OGTT), total cholesterol (t-chol), triglycerides (TG), high-density-lipoprotein chol (HDL-Chol), hemoglobin A1c (HbA1c), electrocardiogram (ECG) and urinary albumin-creatinine ratio [Figure-1]. Additionally, the normoglycemic (FBG <5.6mmol/l) subjects also had all these investigations but only in randomly selected 20%.       A total of 6235 subjects of 10 villages were found eligible for the study. Of them, 4141 (m / f = 1749 / 2392) volunteered for the study. The mean (SD) age of the participants was 37.6 (15.2) years and the values for BMI, WHR, SBP, DBP and FBG were 19.4 (2.9), 0.84 (0.07), 120 (18) mmHg, 77 (12) mmHg and 4.7 (0.89) mmol/l, respectively (Table-1a). The participants, as mentioned, were categorized into hyperglycemic (FBG ³5.6) and normoglycemic (FBG<5.6) groups [figure 1]. Further biochemical investigations are also shown in the same table. Hyperglycemia was found in 7.2% (n=300) and normoglycemia in 92.8% (n=3841) subjects. All of the hyperglycemic and 20% of the randomly selected normoglycemic subjects (n=768) were undertaken for further investigations like cholesterol, TG, HDL, HbA1c, ACR shown in Table-1b. The characteristics of the hyperglycemic and normoglycemic subjects were compared (Table 2). Compared with the normoglycemic, the hyperglycemic subjects had significantly higher age, WHR, WHtR, SBP, DBP and FBG; whereas, they did not differ with respect to sex, social class, family history of HTN and CHD. In contrast, the family history of diabetes was significantly higher among the hyperglycemic group (p<0.01). Fig.1: Algorithm for investigation:     Table 1b: Investigations undertaken for the hyperglycemic and randomly selected groups (n = 976)     Table-3 shows the comparison of characteristics between subjects with and without CHD. The subjects with CHD had a significantly higher age (p<0.001), WHtR (p<0.03), SBP (p<0.01), DBP (p<0.05), FBG (p<0.001) and ACR (p<0.01) than their non-CHD counterpart; whereas, other characteristics like BMI, WHR, Chol, TG, HDL, LDL, VLDL and lipoprotein (a) did not differ. Table 3: Comparison of characteristics between subjects with and without coronary heart disease (CHD)       We also estimated the association of CHD with family income, education, occupation and smoking habits. None of these variables showed any significant association with CHD. In contrast, family history of hypertension and family history of CHD proved to have a significant risk for CHD.     Discussion     Additional merit of the study is that more than 90% of the selected participants volunteered for ECG, OGTT, t-cholesterol, TG, HDL, LDL and ACR in a rural setting. As regards risk factors for CHD, advancing age, diabetes, hypertension, family history of CHD and high ACR are very consistent with other studies.14-16,18-20 Interestingly, smoking habit, general obesity (high BMI), central obesity (high WHR), dyslipidemia (high chol, TG, low HDL) and extremes of social class (affluent or socially deprived) were found not significantly related to CHD. Why these known risk factors are not related to CHD in the study population is not clear. Possibly, the study population was neither obese (mean BMI±SD: 19.4±2.9; WHR: 0.84±0.07) nor dyslipidemic (95% CI: cholesterol, 121 -129, TG, 105 – 117) and not exceeding the thresholds of obesity or dyslipidemia for developing CHD. Consequently, these risk factors were found not contributing to atherosclerosis.   The study concludes that the prevalence of CHD is almost comparable with the Indians and even higher than Japanese and Chinese. Family history of CHD and age over 45 years, and who had hyperglycemia and higher ACR were observed to be the independent predictors of CHD. CHD was found to affect participants irrespective of sex, social class, obesity and lipid status. Although the IFG and diabetes groups appeared to have similar biophysical characteristics, only the diabetes group had a significant risk for CHD. Further studies on a larger sample may be undertaken to confirm the study findings and to explore some unidentified risk factors of CHD. Acknowledgements   1.   Azambuja MI, Levins R. Coronary heart disease (CHD)—one or several diseases? Changes in the prevalence and features of CHD. Perspect Biol Med 2007; 50: 228-42. 3.   Jabara R, Namouz S, Kark JD, Lotan C. Risk characteristics of Arab and Jewish women with coronary heart disease in Jerusalem. Isr Med Assoc J. 2007; 9: 316-20. 5.   Strong M, Maheswaran R, Radford J. Socioeconomic deprivation, coronary heart disease prevalence and quality of care: a practice-level analysis in Rotherham using data from the new UK general practitioner quality and outcomes framework. J Public Health (Oxf) 2006; 28: 39-42. 7.   Musa AKM, Khan AH. Statistical pocket book of Bangladesh 2004: Bangladesh bureau of statistics, planning division, ministry of planning, Government of the Peoples’ Republic of Bangladesh 2006; 437-8. 9.   John L, Nayyar V, Shyla PM, Kanagasabapathy AS. Comparison of cardiovascular risk factors in type II (non-insulin dependent) diabetics with and without coronary heart disease. J Assoc Physicians India. 1993; 4: 84-7. 11.Sayeed MA, Banu A, Khanam PA, Mahtab H and Azad Khan AK. Prevalence of Hypertension in Bangladesh: effect of socioeconomic risk on difference between rural and urban community. Bang Med Res Coun Bull 2002; 28: 7-18. 13.Sayeed MA, Mahtab H, Khanam PA, Ali SMK, Chowdhury RI, Vaalar S, Hussain A and Azad Khan AK. Fasting cut-offs in determining the prevalence of diabetes and intermediate glucose abnormality in a non-obese population. Bang Med Res Counc Bull 2004; 30: 105–114. 15.Silbiger JJ, Ashtiani R, Mehran Attari, Tanya M. Spruill, Mazullah Kamran, Deborah Reynolds, Russell Stein and David Rubinstein. Aheroscerlotic heart disease in Bangladeshi immigrants: risk factors and angiographic findings. Int J Cardiology 2008; 12: 175 [letter]. 17.Rahman MA, Zaman MM. Smoking and smokeless tobacco consumption: Possible risk factors for coronary heart disease among young patients attending a tertiary care cardiac hospital in Bangladesh. Public health J 2008; 122: 1331-1338. 19.Joshi R, Chow CK, Raju PK, Raju R, Reddy KS, MacMahon S, Lopez D, Neal B. Fatal and nonfatal cardiovascular disease and the use of therapies for secondary prevention in a rural region of India. Circulation. 2009; 119: 1950-1955. 21.Nazarethhttp://heartasia.bmj.com/content/2/1/28. abstract - aff-1 I, D’Costa G, Kalaitzaki E, Vaidya R, King M. Angina in primary care in Goa, India: sex differences and associated risk factors. Heart Asia 2010; 2: 28-35. 23.Yusuf S, Reddy S, Ounpuu S and Anand S. Global burden of cardiovascular diseases: Part II: Variations in cardiovascular disease by ethnic groups and geographic regions and prevention strategies. Circulation 2001; 104: 2855-2864. 2026 Ibrahim Medical College. All rights reserved.