Body Mass Index (BMI) in Association with Diabetes, Hypertension, Comorbidity among Patients in the Buea Health District, Cameroon

Background: The rising burden of hypertension and diabetes in sub-Saharan Africa has intensified the risk of chronic kidney disease (CKD), with body mass index (BMI) playing a critical role in metabolic health. However, limited evidence exists on the sociodemographic and clinical factors influencing BMI and comorbidity patterns in Cameroon, particularly among high-risk populations. Methods: A cross-sectional analytical study was conducted between July 2023 and April 2024 in the Buea Health District, involving 400 patients with hypertension and/or diabetes recruited from four healthcare facilities using systematic sampling. Data on sociodemographics, medical history, and lifestyle behaviours were collected via interviewer-administered questionnaires. Anthropometric and clinical measurements, including blood pressure, fasting blood sugar (FBS), and BMI, were recorded. BMI was categorized per WHO standards. Chi-square tests assessed associations between BMI and clinical variables, while binary logistic regression identified predictors of BMI, with results expressed as adjusted odds ratios (AOR) and 95% confidence intervals (CI). Results: Hypertension, diabetes and comorbidity affected 57.5% of participants, with higher prevalence among males, widowed individuals, and those with primary education. A polarized BMI distribution was observed: 43% were overweight or obese, 32% had normal weight, and 25% were underweight. No significant association was found between BMI and hypertension (p = 0.174) or diabetes (p = 0.352). However, elevated FBS was significantly linked to higher BMI (p = 0.015). BMI distribution varied significantly by treatment center (p = 0.001). In regression, regular physical exercise (AOR = 2.815, p < 0.001) and vegetable intake (AOR = 2.545, p = 0.003) were strong predictors of higher BMI. Diabetes, hypertension, and their comorbidity were not statistically significant predictors of CKD. Conclusion: Lifestyle factors are more influential than disease status in determining BMI, underscoring the need for behaviour-centred interventions.