Descriptive epidemiology of blood pressure in a rural adult population in Northern Ghana.

INTRODUCTION

There are limited data on blood pressure (BP) levels in rural populations in sub-Saharan Africa. This is a cause for concern considering high BP contributes to a substantial public health burden in this population.

METHODS

Blood pressure levels were measured in a representative rural sample from Kassena-Nankana District of Northern Ghana, West Africa, and associations with anthropometric indices, age, sex, and time of BP measurement were assessed. This cross-sectional survey was made on a random sample drawn from a population register and included 207 males and 367 females aged between 18 and 65 years. Data collection consisted of anthropometric and blood pressure measurements after questionnaire interviews. Household salt consumption was also measured in 20 randomly selected households.

RESULTS

Overall prevalence of casual high BP was 19.3% (111/574). Age-adjusted mean (standard deviation) systolic BPs (SBPs) and diastolic BPs (DBPs) were 124.25 (18.67) and 69.92 (12.09) mmHg in males and 122.07 (22.01) and 72.11 (12.35) mmHg in females. Mean body mass index (BMI) was 21.78 (3.09) kg/m2; 21.13 (2.27) for males and 22.15 (3.41) kg/m2 for females (p > 0.05). Blood pressures increased with age, 4 and 3 mmHg per decade for SBP and DBP, respectively (p < 0.000). Regression analyses showed that SBP was significantly associated with age, BMI, waist circumference and time of BP measurement (p < 0.000). In multiple regression analyses, age and BMI were independently associated with SBP and DBP in women (p < 0.001). Time of BP measurement was independently associated with SBP but only in men (p < 0.001). There was no increase in BMI with age. Repeat measurements in 89 subjects yielded a regression dilution factor of 0.57 for SBP. Salt consumption per individual was estimated as equivalent to 12.5 g of pure salt/day.

CONCLUSION

Average BPs are not notably high in this predominantly lean rural West African population. Blood pressures do, however, increase as expected with age and BMI. Population-wide approaches need to be developed, appropriate to the level of medical provision, in order to address vascular disease risks resulting from higher than optimal BPs. These should include programs to reduce salt consumption.