High blood pressure and associated risk factors among women attending antenatal clinics in Tanzania

Aim: Hypertension during pregnancy (HDP) is one of the leading causes of maternal and perinatal mortality worldwide. This study examined prevalence and potential risk factors for HDP among pregnant women in Tanzania. Methods: We examined 910 pregnant women, aged at least 20 years, mean gestational age 27 weeks, from rural (n = 301) and urban (n = 609) areas, during their usual antenatal clinic visits. Hypertension was defined as clinic SBP at least 140mmHg or DBP at least 90 mmHg. Dietary assessment included dietary diversity score using 16 food groups. Multiple logistic regression analysis was used to assess the independent association of risk factors associated with prevalence of hypertension. Results: A total of 62 women (6.9%) had HDP, prevalence being higher in urban (8.1%) compared to rural area (4.4%). For the urban area, mother's age [ odds ratio (OR) 1.10, 95% confidence interval (CI) 1.03-1.20], gestational age (OR 1.10, 95% CI 1.02-1.20), mid-upper arm circumference (OR 1.13, 95% CI 1.01-1.23), dietary diversity score (OR 1.31, 95% CI 1.20-1.60) and being HIV-positive (OR 2.40, 95% CI 1.10-5.18) were independently associated with HDP. When adjusted for proteinuria, associations with HIV status and mid-upper arm circumference weakened. In the rural area, HDP risk increased with age and gestational age. Conclusion: Prevalence of HDP was higher in urban compared to rural area, which points at high risk for preterm delivery, low birth weight and future cardiovascular diseases. The observed risk factors identify risk groups to be screened and targeted for prevention. The role of HIV status needs to be further explored.