Indian Consensus for Prevention of Hypertension and Coronary Artery Disease: Indian Consensus Group: Report of a Consensus Development Workshop Conducted by the Indian Society of Hypertension and the International College of Nutrition, New Delhi, 1995

Dietary Approaches to Stop Hypertension via Indo-Mediterranean Foods, May Be Superior to DASH Diet Intervention

Western-type diet with high salt and sugar, sedentary behavior, obesity, tobacco and alcoholism are important risk factors for hypertension. This review aims to highlight the role of western diet-induced oxidative stress and inflammation in the pathogenesis of hypertension and the role of various types of diets in its prevention with reference to dietary approaches to stop hypertension (DASH) diet. It seems that it is crucial to alter the western type of diet because such diets can also predispose all CVDs. Western diet-induced oxidative stress is characterized by excessive production of reactive oxygen species (ROS) with an altered oxidation-reduction (redox) state, leading to a marked increase in inflammation and vascular dysfunction. Apart from genetic and environmental factors, one important cause for differences in the prevalence of hypertension in various countries may be diet quality, deficiency in functional foods, and salt consumption. The role of the DASH diet has been established. However, there are gaps in knowledge about the role of some Indo-Mediterranean foods and Japanese foods, which have been found to decrease blood pressure (BP) by improving vascular function. The notable Indo-Mediterranean foods are pulses, porridge, spices, and millets; fruits such as guava and blackberry and vegetables, which may also decrease BPs. The Japanese diet consists of soya tofu, whole rice, in particular medical rice, vegetables and plenty of fish rich in fish oil, fish peptides and taurine that are known to decrease BPs. Epidemiological studies and randomized, controlled trials have demonstrated the role of these diets in the prevention of hypertension and metabolic diseases. Such evidence is still meager from Japan, although the prevalence of hypertension is lower (15-21%) compared to other developed countries, which may be due to the high quality of the Japanese diet. Interestingly, some foods, such as berries, guava, pumpkin seeds, carrots, soya beans, and spices, have been found to cause a decrease in BPs. Omega-3 fatty acids, fish peptide, taurine, dietary vitamin D, vitamin C, potassium, magnesium, flavonoids, nitrate and l-arginine are potential nutrients that can also decrease BPs. Larger cohort studies and controlled trials are necessary to confirm our views.

Are Gujarati Asian Indians 'older' for their 'vascular age' as compared to their 'Chronological age'?

BACKGROUND

South Asians are known to carry higher burden of cardiovascular diseases when compared with their Caucasian counterparts.

AIM

This study was designed to evaluate whether vascular age is advanced for Gujarati Asian Indians as matched to their chronological age in apparently healthy, asymptomatic population. We have also assessed the contributing risk factors for premature vascular ageing.

DESIGN

It was cross-sectional study of 2483 individuals of Gujarat state in Western India having no past or present history of major illness including cardiovascular diseases.

METHOD

The vascular age of the population was calculated using Framingham vascular age calculator. A relationship between risk factor prevalence and vascular ageing was evaluated using univariate analysis of variance.

RESULTS

The mean chronological age of the study population was 46.8 (±10.35) years whereas mean vascular age was 53.34 (±16.05) years, and the difference (6.54±9.5) between both was statistically significant (P < 0.0001). Contributory risk factors for advanced vascular age apart from chronological age (75.4%) and male gender (66.2%) were the presence of dyslipidemia (60.4%) hypertension (57.34%) and increased waist circumference (WC) (male 39.7%, female 29%). Results of regression analysis showed that vascular age progression was highly associated with blood pressure (19.9, 95% CI: 14.34-27.63), followed by smoking (15.23, 95% CI: 8.4-27.59), and blood sugar (12.97, 95% CI: 3.48-48.25).

CONCLUSION

The Gujarati Asian Indians are subjected to premature vascular ageing and henceforth routine screening for vascular age and risk factors prevalence is strongly advocated in this ethnic group.

Type of vegetarian diet, obesity and diabetes in adult Indian population

Background

To investigate the prevalence of obesity and diabetes among adult men and women in India consuming different types of vegetarian diets compared with those consuming non-vegetarian diets.

Methods

We used cross-sectional data of 156,317 adults aged 20–49 years who participated in India’s third National Family Health Survey (2005–06). Association between types of vegetarian diet (vegan, lacto-vegetarian, lacto-ovo vegetarian, pesco-vegetarian, semi-vegetarian and non-vegetarian) and self-reported diabetes status and measured body mass index (BMI) were estimated using multivariable logistic regression adjusting for age, gender, education, household wealth, rural/urban residence, religion, caste, smoking, alcohol use, and television watching.

Results

Mean BMI was lowest in pesco-vegetarians (20.3 kg/m²) and vegans (20.5 kg/m²) and highest in lacto-ovo vegetarian (21.0 kg/m²) and lacto-vegetarian (21.2 kg/m²) diets. Prevalence of diabetes varied from 0.9% (95% CI: 0.8-1.1) in person consuming lacto-vegetarian, lacto-ovo vegetarian (95% CI:0.6-1.3) and semi-vegetarian (95% CI:0.7-1.1) diets and was highest in those persons consuming a pesco-vegetarian diet (1.4%; 95% CI:1.0-2.0). Consumption of a lacto- (OR:0.67;95% CI:0.58-0.76;p < 0.01), lacto-ovo (OR:0.70; 95% CI:0.51-0.96;p = 0.03) and semi-vegetarian (OR:0.77; 95% CI:0.60-0.98; p = 0.03) diet was associated with a lower likelihood of diabetes than a non-vegetarian diet in the adjusted analyses.

Conclusions

In this large, nationally representative sample of Indian adults, lacto-, lacto-ovo and semi-vegetarian diets were associated with a lower likelihood of diabetes. These findings may assist in the development of interventions to address the growing burden of overweight/obesity and diabetes in Indian population. However, prospective studies with better measures of dietary intake and clinical measures of diabetes are needed to clarify this relationship.

Frequency of fish intake and diabetes among adult Indians

OBJECTIVES

Recent studies have shown that the choice of foods plays a role in diabetes prevention. However, little empirical evidence on this association exists in developing countries. We aimed to examine the association between frequency of fish intake and self-reported diabetes status among adult men and women in India.

METHODS

Analysis of cross-sectional data from participants in India's third National Family Health Survey conducted during 2005-2006 was performed. Associations between fish intake, determined by frequency of consumption (daily, weekly, occasionally, and never), and self-reported diabetes were estimated using multivariable-adjusted models in 99,574 women, 56,742 men, and 39,257 couples aged 20-49 years after adjusting for frequency of consumption of other food items, body mass index (BMI) status, tobacco smoking, alcohol drinking, watching television, age, education, living standard of the household, and place of residence.

RESULTS

After adjustment for other dietary, lifestyle, and socioeconomic and demographic characteristics, odds of diabetes were 2 times higher (odds ratio [OR]: 2.02; 95% confidence interval [CI], 1.59-2.57; p < 0.0001) among those who reported consuming fish daily compared to those who never consumed fish. Weekly fish intake was also associated with a higher odds of having diabetes (OR: 1.55; 95% CI, 1.25-1.93; p < 0.0001). The adjusted effect of daily fish intake on diabetes was greater among men (OR: 2.46; 95% CI, 1.66-3.65) than among women (OR: 1.72; 95% CI, 1.26-2.33). In cross-spousal sensitivity analysis, the odds of a husband having diabetes was also associated with wife's daily/weekly consumption of fish (OR: 1.36; 95% CI, 0.92-2.01) and the odds of a wife having diabetes was also associated with husband's daily/weekly consumption of fish (OR: 1.21; 95% CI, 0.87-1.68).

CONCLUSIONS

In a large nationally representative sample of adult men and women in India, daily or weekly fish intake was positively associated with the presence of diabetes. However, this is an observational finding and uncontrolled confounding cannot be excluded as an explanation for the association. More epidemiological research with better measures of food intake and clinical measures of diabetes is needed in a developing country setting to validate the findings.

Association between legume intake and self-reported diabetes among adult men and women in India

BACKGROUND

It is postulated that a diet high in legumes may be beneficial in preventing diabetes. However, little empirical evidence on this association exists in developing countries. We aimed to examine the association between legume intake and self-reported diabetes status in adult men and women in India.

METHODS

The analysis is based on a population-based cross sectional study of 99,574 women and 56,742 men aged 20-49 years included in India's third National Family Health Survey conducted in 2005-06. Association of legume intake, determined by the frequency of consumption of pulses and beans (daily, weekly and occasionally or never), with the reported prevalence of diabetes were estimated using multiple logistic regression after adjusting for frequency of consumption of other food items, BMI status, tobacco smoking, alcohol drinking, watching television, age, education, living standard of the household, residence and geographic regions.

RESULTS

Daily (OR: 0.71; 95% CI: 0.59-0.87; p=0.001) and weekly (OR: 0.66; 95% CI: 0.54-0.80; p<0.001) legumes intake were associated with a significantly reduced prevalence of diabetes among adult Indian women even after controlling for the effects of potentially confounding factors, whereas non-significant inverse associations were observed in men.

CONCLUSION

Daily or weekly intake of legumes was inversely associated with presence of diabetes in the Indian population. However, this is an observational finding and uncontrolled confounding cannot be excluded as an explanation for the association. More epidemiological research with better measures of legumes intake and clinical measures of diabetes is needed to clarify this relationship.

Sib-recruitment for studying migration and its impact on obesity and diabetes

BACKGROUND

Urban-rural comparisons are of limited relevance in examining the effects of urban migration in developing countries where urbanisation is due to growth of existing urban populations, expansion of urban boundaries, and rural in-migration. Cultural, genetic and life-style backgrounds of migrants and host populations further limit the value of rural-urban comparisons. Therefore we evaluated a sib-comparison design intended to overcome the limitations of urban-rural comparisons.

METHODS

Using the framework of a current cardiovascular risk factor screening study conducted in Indian factories, we recruited the non-migrant rural sibs of migrant urban factory workers and the urban sibs of non-migrant factory workers. The response rate, completed interviews and examinations conducted were assessed. Adequacy of generic food frequency questionnaires and WHO quality of life questionnaire were assessed.

RESULTS

All the urban factory workers and spouses approached agreed to be interviewed. Of the 697 participants interviewed, 293 (42%) had at least one rural dwelling sibling. Twenty (22%) siblings lived further than 100 km from the study site. An additional 21 urban siblings of non-migrant factory workers were also investigated to test the logistics of this element of the study. Obesity (BMI >25 kg/m2) was more common in rural sibs than urban factory workers (age adjusted prevalence: 21.1% (17.1 to 25.0) vs. 16.1% (11.9, 20.3). Diabetes prevalence (fasting plasma glucose greater than 126 mg/dl) was higher than expected (age-adjusted prevalence: 12.5% (22 out of 93) in urban migrants and 4.5% (8 out of 90) in rural non-migrant sibs.

CONCLUSION

The sib-comparison design is robust and has been adopted in the main study. It is possible that simple urban-rural study designs under-estimate the true differences in diabetes risk between migrants and non-migrants.

Body fat percent by bioelectrical impedance analysis and risk of coronary artery disease among urban men with low rates of obesity: the Indian paradox

OBJECTIVE

To determine the association between body fat percent and prevalence of coronary artery disease (CAD) and coronary risk factors in subjects with low rates of obesity.

SUBJECTS AND METHODS

We randomly selected 850 men, aged 25 to 64 years. The survey methods were questionnaire and bioelectrical impedance analysis for body composition. Subjects were divided into high-fat (n = 357), over-fat (n = 230), normal-fat (n = 200) and under-fat (n = 63) based on criteria of body-fat percent analysis.

RESULTS

The prevalence of CAD and the coronary-risk factors hypercholesterolemia, hypertension, diabetes, mellitus and sedentary lifestyle were significantly associated with high and moderate body fat percent despite low body-mass index (23.6+/-4.1 kg/m2). Mean total cholesterol, triglycerides and blood pressure were significantly associated with high and moderate body fat percent. The prevalence of smoking was weakly but inversely associated with high body-fat percent. Mean HDL cholesterol was positively associated with high body-fat percent. Body mass index was positively associated with high body-fat percent.

CONCLUSIONS

High and moderate body-fat-percent subjects were associated with high prevalence of CAD and the coronary-risk factors hypertension, diabetes mellitus, higher body-mass index and sedentary lifestyle.

Social class, coronary risk factors and undernutrition, a double burden of diseases, in women during transition, in five Indian cities

OBJECTIVE

To find out the association between social class and coronary risk factors in women.

DESIGN AND SETTING

Cross-sectional surveys were conducted in six-twelve urban streets in each of five cities from various regions of India following a common study protocol and criteria of diagnosis.

SUBJECTS AND METHODS

We randomly selected 3257 women, aged 25-64 years inclusive, from the cities of Moradabad (n=902), Trivandrum (n=760) Calcutta (n=410), Nagpur (n=405) and Bombay (n=780). Evaluation was by questionnaires validated at Moradabad. All subjects, after pooling of data, were divided into social class 1 (n=985), social class 2 (n=790), social class 3 (n=674), social class 4 (n=602) and social class 5 (n=206), based on various attributes of socioeconomic status.

RESULTS

The prevalence of hypertension, diabetes mellitus, family history of coronary disease, obesity, central obesity and sedentary lifestyle were significantly associated with higher social classes and tobacco consumption was not associated with social class. Oral contraceptive intake and postmenopausal status were also more common among higher social classes, which may be due to more education and a longer lifespan among the higher social classes, respectively. Mean total cholesterol, high density lipoprotein cholesterol, systolic and diastolic blood pressure, mean body mass index and waist-hip ratio showed significant association with higher social classes. Mean age, body weight, body mass index, waist-hip ratio, systolic and diastolic blood pressure, total cholesterol and 2-h blood glucose were significantly positively correlated with social class, as assessed by Spearman's rank correlation. Higher social classes 1-3 were more common in Trivandrum and Bombay than in Moradabad. The prevalence of hypertension, diabetes mellitus and being overweight (body mass index >25 kg/m2) were also more common in Trivandrum and Bombay compared to Moradabad. Undernutrition was negatively associated with higher social classes and was more common in Moradabad and Nagpur than Trivandrum.

CONCLUSIONS

Higher social classes among Indian urban women have a higher prevalence of coronary risk factors, hypertension, diabetes mellitus, being overweight, central obesity, sedentary lifestyle, family history of coronary disease, oral contraceptive intake and postmenopausal status. Mean concentrations of total and high density lipoprotein cholesterol were also significantly associated with higher social classes.

Low fat intake and coronary artery disease in a population with higher prevalence of coronary artery disease: the Indian paradox

OBJECTIVE

To determine the association between saturated fat intake and prevalence of coronary artery disease (CAD) and coronary risk factors.

DESIGN AND SETTING

Total community cross sectional survey of 20 urban streets out of 196 streets, in the city of Moradabad in north India.

SUBJECTS AND METHODS

Adult population between 25 to 64 years inclusive comprised of 1806 subjects (904 men, 902 women) were divided into three groups according to level of saturated fat intake as assessed by 7-day dietary intake records (very low < 7%, low 7 to 10%, high > 10% energy (en) per day).

RESULTS

We examined the relationship between CAD risk and levels of % en from fat intake. Low (7 to 10% en/day) and high (> 10% en/day) saturated fat were positively and significantly associated with higher prevalence of CAD. The prevalence of coronary risk factors (hypertension, hypercholesterolemia, obesity and sedentary lifestyle) were significantly higher among subjects with low and high saturated fat intake compared to subjects with very low (< 7%) saturated fat intake. Logistic regression analysis with adjustment for age showed that hypercholesterolemia (OR: men 0.89, women 0.68), hypertension (men 0.92, women 0.56), physical activity (men 0.80, women 0.36), obesity (men 0.82, women 0.88) and smoking (0.70 men) were significant risk factors of CAD. Low and high saturated fat intake were associated with more prestigious occupations, higher and middle income status and better educational levels compared to very low saturated fat intake.

CONCLUSIONS

The prevalence of CAD and coronary risk factors was higher in urban Indians with low and high saturated fat intake than those with lower saturated fat intake. These findings suggest that the saturated fat intake should be < 7% en/day for prevention of CAD in Indians.

Serum cholesterol and coronary artery disease in populations with low cholesterol levels: the Indian paradox

OBJECTIVE

To examine the relation between serum cholesterol and coronary artery disease prevalence below the range of cholesterol values generally observed in developed countries.

DESIGN AND SETTING

Cross-sectional survey of two randomly selected villages from Moradabad district and 20 randomly selected streets in the city of Moradabad.

SUBJECTS AND METHODS

3575 Indians, aged 25-64 years including 1769 rural (894 men, 875 women) and 1806 urban (904 men, 902 women) subjects. The survey methods were questionnaires, physical examination and electrocardiography.

RESULTS

The overall prevalences of coronary artery disease were 9.0% in urban and 3.3% in rural subjects and the prevalences were significantly (P<0.001) higher in men compared to women in both urban (11.0 vs. 6.9%) and rural subjects (3.9 vs. 2.6%). The average serum cholesterol concentrations were 4.91 mmol/l in urban and 4.22 mmol/l in rural subjects without any sex differences. The prevalences of coronary artery disease were significantly higher among subjects with low and high serum cholesterol concentration compared to subjects with very low cholesterol and showed a positive relation with serum cholesterol within the range of serum cholesterol level studied in both rural and urban in both sexes. Among subjects with low serum cholesterol, there was a higher prevalence of coronary risk factors, hypertension, diabetes, obesity and sedentary lifestyle. Serum cholesterol level showed a significant positive relation with low density lipoprotein cholesterol and triglycerides in all the four subgroups. Logistic regression analysis after pooling of data from both rural and urban, with adjustment of age showed that low serum cholesterol level (odds ratio: men 0.96, women 0.91) had a positive strong relation with coronary artery disease and there was no evidence of any threshold. Diabetes mellitus (men 0.73, women 0.74) and sedentary lifestyle (men 0.86, women 0.74) were significant risk factors of coronary disease in both sexes. Hypertension (men 0.82, women 0.64) and smoking (men 0.81, women 0.52) were weakly associated with coronary disease in men but not in women.

CONCLUSION

Serum cholesterol level was directly related to prevalence of coronary artery disease even in those with low cholesterol concentration (<5.18 mmol/l). It is possible that some Indian populations may benefit by increased physical activity and decline in serum cholesterol below the range of desired serum cholesterol in developed countries.

Prevalence and risk factors of hypertension and age-specific blood pressures in five cities: a study of Indian women. NKP Salve Institute of Medical Sciences, Nagpur, India. Five City Study Group

OBJECTIVE

To measure the prevalence of hypertension and age-specific blood pressure in urban populations from five Indian cities. Cross-sectional surveys were conducted in six-twenty urban streets in different cities from five different corners of India, using similar methods of sample selection and criteria. There were 3212 randomly selected women from Moradabad (n=902), Trivandrum (n=760), Calcutta (n=365), Nagpur (n=405) and Bombay (n=780), aged 25-64 years, inclusive. Evaluation was by a physician and a dietitian, an administered questionnaire, a physical examination and using a sphygmomanometer. The diagnosis of hypertension was based on old World Health Organisation criteria and new World Health Organisation/International Society of Hypertension criteria. The prevalence of hypertension (>140/90 mm Hg) was significantly (P<0.01) high in Trivandrum, South India (30.7%), and Bombay, West India (28.0%), compared to Moradabad, which is in northern India (22.6%), Nagpur, in central India (24.2%), and Calcutta, in east India (19.1%). Mean systolic and diastolic blood pressures were significantly higher in Trivandrum and Bombay compared to the other three cities. The overall prevalence of hypertension was 25.6% (n=823) and isolated diastolic hypertension was the most common form of hypertension (50.5%, n=1506) in the five Indian cities. According to old criteria, the overall prevalence of hypertension (>160/95 mm Hg) was 14.8% (n=481). Multivariate logistic regression analysis on pooled data from the five cities, after adjustment for age, showed that age (odds ratio 1.16), body mass index (1.68) and obesity were strongly associated with hypertension. A sedentary lifestyle and salt intake were weakly associated and alcohol intake was not a factor with these women.

Association of higher saturated fat intake with higher risk of hypertension in an urban population of Trivandrum in south India

Saturated fat intake appears to be a risk factor of insulin resistance which is important in the pathogenesis of diabetes and cardiovascular disease. This study aims to demonstrate whether saturated fat intake may be a risk factor of hypertension. Cross-sectional survey in six randomly selected streets in Trivandrum city in south India was conducted to study 1497 randomly selected subjects (737 males and 760 females) of 25-64 years of age. The prevalence of hypertension by Joint National Committee V criteria (> 140/90 were 34.6% (n = 255) in males and 30.7% (n = 234) in females. The consumption of food groups showed that they were within desirable limits. However, the intake of fruit, vegetable, legume and coconuts was lower and saturated fat intake higher (> 10% kcal/day), although total fat intake was within desirable limits. Total and saturated fat intake, and the consumption of coconut oil and butter, flesh foods, milk and yogurt as well as sugar and jaggery were significantly associated with hypertension. Total visible fat (> 20 g/day) intake was positively associated whereas fruit, vegetable, legume and coconut intake (< 400 g/day) was inversely associated with hypertension. Salt intake (> 8 g/day), smoking and illiteracy were not associated with hypertension. Multivariate logistic regression analysis showed that saturated fat intake, age and body mass index were independently and strongly associated with hypertension whereas fruits, vegetable, legume and coconuts, coconut oil and butter and alcohol (males) intakes were weakly associated with hypertension. The odds ratio indicate higher risk of hypertension due to higher intake of saturated fat in both sexes (mean: odds ratio, 1.07, 95% confidence interval 1.05-1.09; women, 1.08, 1.06-1.12, P < 0.01). Significant determinants of hypertension were higher saturated fat, particularly coconut oil, and lower fruit, vegetable, legume and coconuts, particularly legumes and coconuts in the diet, apart from conventional risk factors.