Patterns and predictors of undiagnosed and uncontrolled hypertension: observations from a poor-resource setting

Early detection is the cornerstone of hypertension management; still majority remains undetected until complications arise, especially in poor-resource settings. Paucity of information regarding undiagnosed and uncontrolled hypertension in eastern India thus called for a detailed investigation involving a representative sample of adults in Malda, one of the poorest districts in the region. In a cross-sectional study, between October 2013 and July 2014, using multistage random sampling with probability-proportional-to-size, 18 028 consenting adults were interviewed. Diagnosed cases were defined as uncontrolled if they still had hypertensive level of blood pressure (according to JNC-VIII criteria) while those detected during this study were defined as undiagnosed. Descriptive and regression analyses were performed using SAS version 9.3.2. Among 18 028 participants, 4695 (26.04% (95% confidence intervals: 95% CI=25.40-26.68)) had hypertension, of which 3937 (83.86% (82.80-84.91)) were undiagnosed and 548 (72.30 (69.10-75.49)) had uncontrolled hypertension. Relatively older subjects (adjusted Odds ratio (aOR)_{41-60 years}=0.34 (95% CI=0.26-0.43) and aOR_{>60 years}=0.29 (0.21-0.38)), who were divorced/separated/widowed/widower (aOR=0.76 (0.61-0.95)), had higher education (aOR=0.61 (0.43-0.88)), better socio-economic status (SES) (aOR_Middle=0.77 (0.60-0.99) and aOR_Upper=0.64 (0.48-0.85)) and urban residence (aOR=0.44 (0.36-0.55)) were less likely while subjects who belonged to backward castes (aOR=1.37 (1.15-1.64)) were more likely to have undiagnosed hypertension. Odds of having uncontrolled hypertension were higher among participants aged >60 years (aOR=2.25 (1.27-3.99)). Burden of hypertension (diagnosed and undiagnosed) was high in Malda district of West Bengal. Significant predictors of undiagnosed hypertension were young age, backward caste, poor education and lower SES, while older subjects had poor control. Thus, appropriate surveillance targeting these at-risk groups might be effective in controlling hypertension in similar poor-resource settings.