Prevalence of hypertension and selected cardiovascular risk factors among adolescents in selected rural and urban secondary schools in Botswana

Abstract

Background: Adolescent hypertension and other cardiovascular risk factors tend to track into adulthood. Consequently, there is a need to determine the prevalence of hypertension and pre-hypertension, and its co-existence with glycaemia, obesity, tobacco and alcohol use among senior secondary school students in Botswana.

Methods: A cross-sectional study was undertaken between December 2015 and March 2016 among students in selected rural and urban senior secondary schools in Botswana. Data were collected through a self-administered questionnaire, measurements and fasting blood glucose testing. Participants were asked about cigarette smoking, alcohol use and levels of physical activity. Body weight, height, waist circumference, blood pressure and fasting blood glucose levels were measured. Hypertension, pre-hypertension, overweight and obesity were defined based on gender, age and height from normative tables.

Results: A total of 252 students with a mean age (standard deviation) of 17.1 (0.9) years participated in the study. Rural students were older than urban students (17.5 vs 16.7 years; p < 0.001). The prevalence of hypertension and prehypertension were 13.1 and 15.5%, respectively. Physical inactivity (37.7%), overweight/obesity (10.3%) and alcohol intake (9.1%) were also prevalent. Cigarette smoking was rare (2.0%). Impaired fasting glucose levels were found in 1.6% of participants, and none had diabetes mellitus. Hypertension ( p < 0.001) and cigarette smoking (p = 0.019) were more prevalent among male than female participants. Female students were more likely to be overweight or obese than male students ( p < 0.001). There were no urban-rural differences in hypertension, pre-hypertension and smoking. Urban students were more likely to drink alcohol than rural students (p = 0.008).

Conclusions: Hypertension, overweight/obesity and alcohol intake were common among these adolescents in Botswana. Strategies to reduce the risk factors of cardiovascular diseases should be urgently developed and implemented to prevent cardiovascular disease-related morbidity and mortality in the future.

Keywords: Botswana; adolescents; cardiovascular risk factors; hypertension.