Body Mass Index, Blood Pressure and Hypertension Subtypes among Untreated Hypertensive Cameroonians

Abstract

Aims: To study the prevalence of hypertension hemodynamic subtypes, prehypertension, hypertension (HTN) stages 1 and 2 as well as to evaluate the influence of overweight and obesity on those prevalences among untreated hypertensive Cameroonians. Study Design: This study was descriptive and cross-sectional. Place and Duration of the Study: Participants were randomly selected in Yaounde, Nkongsamba and Foumban from January 2009 to October 2012. Methodology: It involved 7042 Cameroonians of both sexes aged 18-85 years old. Blood pressure categories were defined using the 7th report of Joint National committee on hypertension. Hypertension subtypes were defined as Isolated Systolic Hypertension (ISH) [Systolic Blood Pressure (SBP)≥140 mmHg and Diastolic Blood Pressure (DBP) < 90 mm Hg]; Isolated Diastolic Hypertension (IDH) (SBP<140 and DBP≥90); Systodiastolic Hypertension (SDH) (SBP≥140 and (DBP) ≥ 90). Participants were classified based on their body mass index (BMI) as obese (BMI ≥30 kg/m2), overweight (25 ≤BMI≤ 29.9) and normal weight (18.5 ≤ BMI ≤ 24.9). Results: Close to 1/3 of individuals (2089) were pre-hypertensive (28.03% women vs 31.30% men, P<.001). 14.3% participants (14.28 % women and 14.32% men, P = .05) already suffering from hypertension stage 2, were diagnosed for the first time. IDH and SDH were the predominant subtypes: IDH (44.23% or 3115 participants), SDH (34.07%) vs ISH (21.7%) and varied with BMI classes. Distribution of frequencies (%) was the following for Normal weight: ISH (30.8%); IDH (41.3%), SDH (27.9%). Overweight: ISH (18.9%); IDH (46.8%), SDH (34.2%). Obese: ISH (15.3%); IDH (44.6%), SDH (40%). Fatness and waist circumference were predictors of IDH and ISH respectively. Conclusion: Obesity was associated with HTN in all age groups and both sexes. IDH and SDH in Cameroon are not only associated with increasing age, but also are prevalent in most cases of obesity induced HTN. This suggests that there is a need to improve prevention and surveillance measures, tailored towards specific subtypes.