Prevalence and risk factors for prehypertension and hypertension in five Indian cities
Background There are few studies detailing the prevalence of prehypertension and hypertension in India. Methods Men and women, over 25 years of age were included. After completion of a dietitian-administered questionnaire followed evaluation by a physician, physical examination and blood pressure measurement. Cross-sectional survey screened 6940 subjects, (3507 men (M), 3433 women (W): 1993-96) from cities located in five corners of India (Kolkata, n = 900; Nagpur, n = 894; Mumbai, n = 1542; Thiruanantpuram, n = 1602; Moradabad, n = 2002). Prehypertension (BP 130-139/85-89 mm Hg) and hypertension (BP ≥ 140/90 mm Hg) were diagnosed according to the European Society of Cardiology criteria. Results Prevalence of prehypertension and hypertension, respectively, was significantly greater in South India (Trivandrum: W 31.5; 31.9%; M 35.1; 35.5%) and West India (Mumbai: W 30.0; 29.1%; M 34.7; 35.6%) compared to North India (Moradabad: W 24.6; 24.5%; M 26.7; 27.0%) and East India (Kolkata: W 20.9; 22.4%; M 23.5; 24.0%). Subjects with prehypertension and hypertension were older, had a higher BMI, central obesity and a sedentary lifestyle. They had a higher salt and alcohol intake, with greater oral contraceptive usage (W). Multivariable logistic regression analysis revealed strong positive associations of hypertension with age, central obesity, BMI, sedentary lifestyle, salt and alcohol intake and oral contraceptive usage (W). Fruit, vegetable and legume intake showed inverse associations, tobacco intake showed none. One in four with hypertension was aware of their diagnosis and of those receiving treatment, one in three had well-controlled hypertension. Conclusions There is little awareness that prehypertension and hypertension are public health issues in India. Ageing population, central obesity, sedentary lifestyle, excessive salt and alcohol, lower fruit, vegetable and legumes intake increase risk for blood pressure elevation.