District specific correlates for hypertension in Kaoma and Kasama rural districts of Zambia.

INTRODUCTION: Hypertension a major risk factor for cardiovascular disease and is the most widely recognized modifiable risk factor for this disease. There is little information on the prevalence and risk factors for hypertension in Zambia, and in particular in rural areas of the country. In order to contribute to the existing global literature on hypertension, particularly in rural Zambia, this study was conducted to determine the prevalence of hypertension and its correlates in two rural districts of Zambia, namely Kaoma and Kasama.
METHODS: A cross-sectional study using a modified World Health Organization (WHO) global non communicable diseases (NCD) surveillance initiative NCD-STEPwise approach was used. Proportions were compared using the Yates' corrected χ2 test, and a result yielding a p-value of less than 5% was considered significant. Bivariate and multivariate logistic regression analyses were conducted. Factors that were significantly associated with the outcome in bivariate analyses were considered in a multivariate logistic regression analysis using a backward variable selection method. Adjusted odds ratios (AOR) and their 95% confidence intervals (CI) were reported.
RESULTS: In total, 895 participants from Kaoma and 1198 participants from Kasama took part in the surveys. Overall, 25.8% participants (27.5% male, 24.6% female; p=0.373) in Kaoma and 30.3% (31.3% male, 29.5% female; p=0.531) in Kasama were hypertensive. In Kaoma, age and BMI were independently associated with hypertension. Compared with participants aged 45 years or older, participants aged 25-34 years were 60% (AOR=0.40, 95% CI [0.21, 0.56]) less likely to be hypertensive. Participants with BMI <18.5 and 18.5-24.9 were 54% (AOR=0.46, 95% CI [0.30, 0.69]) and 31% (AOR=0.69, 95% CI [0.49, 0.98]) less likely to be hypertensive compared with participants with BMI ≥30. In Kasama, age, smoking and heart rate were significantly associated with hypertension in multivariate analysis. Participants 25-34 years were 49% (AOR=0.51, 95% CI [0.41, 0.65]) less likely to be hypertensive compared with participants 45 years or older. Compared with participants who were non-smokers, smokers were 21% (AOR=1.21, 95% CI [1.02, 1.45]) more likely to be hypertensive. Participants who had heart rate >90 beats/min were 59% (AOR=1.59, 95% CI [1.17, 2.16]) more likely to be hypertensive compared with participants who had heart rate 60-90 beats/min.
CONCLUSIONS: The findings reveal that hypertension is prevalent among rural residents in Kaoma and Kasama, Zambia. The disease is highly associated with age, BMI, smoking and heart rate. Efficient preventive strategies are needed to halt the growing trend of non-communicable diseases through the control of risk factors highlighted in this study.