Association of hypertension with infection and inflammation in a setting of disadvantage in rural India.

Abstract

We assessed the association of hypertension with markers of inflammation and infection in a rural and disadvantaged Indian population. In a case-control study, we age- and gender-matched 300 cases with hypertension to 300 controls without hypertension. Blood pressure was measured according to a strict protocol. We measured markers of inflammation and infection including serum high-sensitivity C-reactive protein (hs-CRP), blood lymphocyte count, serum homocysteine, tooth loss, overcrowding and exposure to fecal contamination. Multivariable conditional logistic regression was used to determine their association with hypertension. Median serum hs-CRP was 42% greater in cases than controls, while median serum homocysteine was 10% greater. In multivariable conditional logistic regression, elevated homocysteine (OR 1.75, 95% CI 1.09-2.82), greater lymphocyte count (OR 1.49, 95% CI 1.01-2.01) and exposure to fecal contamination, defined as a distance from the field used for toilet purposes to the household of ≤50 m (OR 2.38, 95% CI 1.07-5.29), were independently associated with hypertension in this rural population. In separate analyses for each gender, elevated hs-CRP (OR 2.62, 95% CI 1.04-6.58) was associated with hypertension in men, whereas edentulism (OR 4.75, 95% CI 1.62-13.96) was associated with greater odds of hypertension in women. Our findings demonstrate specific associations between hypertension and markers of inflammation and infection including hs-CRP, homocysteine, lymphocyte count, edentulism and exposure to fecal contamination. Thus, strategies aimed at reducing inflammation and infection may reduce the burden of hypertension in such settings of disadvantage in rural India.