Prevalence of hypertension and its associated factors among adults in Islamabad, Pakistan

Cardiovascular diseases (CVD) are a major public health concern worldwide with South Asians being at a much higher risk of developing CVD. Hypertension is the commonest cardiovascular disorder. It has cardiovascular, cerebro-vascular and renal complications, which lead to increased morbidity and mortality. It is a modifiable and preventable condition. Twenty four percent of Americans are hypertensives. Different studies on hypertension in Pakistan have shown a relatively high prevalence of hypertension. The National Health Survey of Pakistan (NHSP) estimated the prevalence of hypertension in Pakistan to be 17.9%, but did not include Islamabad in is sample. Islamabad is a multiethnic city with people from almost all races and tribes Iiving in it; having an overall literacy of 72% compared to 38.9% for the rest of Pakistan. There was need to assess the prevalence and associated factors of hypertension in Islamabad. A two stage cluster sampling technique was employed for a cross-sectional study to draw a sample of 789 individuals aged 18 years and above in urban Islamabad, during July- December 2001. A pre-tested questionnaire in Urdu, after taking informed consent, was administered. Height, weight, and blood pressure (BP) were measured using standard methodology. Hypertension was defined as resting systolic BP of ≥140 mm Hg and/or resting diastolic BP of ≥90 mm Hg, based on the mean of six readings on three different occasions and/or taking anti-hypertensive medication. There were 632 (78.6%) males and 172 (21.4%) females in the study. The overall prevalence of hypertension was I7.0% [95% CI (I4.3 - 20.0)]. In the final multivariate logistic model hypertensives were more likely to be females as compared to nonhypertensives [OR = 1.8, 95% CI (1.1 - 2.8)], while adjusting for age, occupation, tobacco use, body mass index (BMI) and family history. Hypertensives were more likely to be involved in sedentary occupations as compared to non-hypertensives [OR = 2.6, 95% A Q-2 - 5.8)1. Taking BMI \u3c25k/m2 as reference category and adjusting for the t 1V effect of other variables in the model, hypertensives were more likely to have BMI \u3e25kglm2 [OR = 2.3, 95vo CI (1.5 - 3.5)] as compared to non-hyperrensives. Hypertensives were more likely to be tobacco users as compared to non-hypertensives [OR = 2-3, 95% CI (1.3 – 3.9)]. An interaction between age and family history of hypertension was also significant in the final multivariate logistic model, showing that when family history was present the risk of developing hypertension increased substantially with increase in age. The high prevalence of hypertension, shown by this first report of a population-based study, to estimate the prevalence of hypertension and identify its associated factors in Islamabad warrants immediate action. Of the factors found to be associated with hypertension in this study tobacco use, occupation and BMI are modifiable. Interventions to reduce the risk of development of hypertension should be initiated immediately. Further research is needed to assess established risk factors that have not been addressed by this study