Association of body weight and physical activity with blood pressure in a rural population in the Dikgale village of Limpopo Province in South Africa

BACKGROUND: Africa is faced with an increasing burden of hypertension attributed mainly to physical inactivity and obesity. Paucity of population based evidence in the African continent hinders the implementation effective preventive and control strategies. The aim of this study was to determine the association of body weight and physical activity with blood pressure in a rural black population in the Limpopo Province of South Africa. METHODS: A convenient sample of 532 subjects (396 women and 136 men) between the ages 20-95 years participated in the study. Standard anthropometric measurements, blood pressure, and physical activity were recorded by trained field workers. RESULTS: Anthropometric measurements showed that a high percentage of women were significantly (p < 0.001) overweight and obese than men. Hypertension was significantly high among women (38.1%) compared to men (27.9%). In the univariate analysis mean body mass index (BMI), waist circumference (WC), hip circumference (HC) and waist hip ratio (WHR) showed a significant positive association (p ≤ 0.05) with systolic and diastolic BP in women, and only WHR was statistically significant in men. The odds of being hypertensive also increased with BMI, WC and WHR in both women and men, including HC in women. No relationship was found between physical activity and high blood pressure. In the multivariate analysis only increase in HC and WHR was consistently associated with increase in SBP in women and WHR with hypertension in men. CONCLUSIONS: The study findings indicate that women in this black South African rural population are overweight and obese than men and are at higher risk of hypertension as determined by selected anthropometric parameters.