Changes in body mass index, obesity, and overweight in Southern Africa development countries, 1990 to 2019: Findings from the Global Burden of Disease, Injuries, and Risk Factors Study

Background High body mass index (BMI) is associated with stroke, ischemic heart disease (IHD), and type 2 diabetes mellitus (T2DM). An epidemiological analysis of the prevalence of high BMI, stroke, IHD, and T2DM was conducted for 16 Southern Africa Development Community (SADC) using Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study data. Methods GBD obtained data from vital registration, verbal autopsy, and ICD codes. Prevalence of high BMI (≥25 kg/m2), stroke, IHD, and T2DM attributed to high BMI were calculated. Cause of Death Ensemble Model and Spatiotemporal Gaussian regression was used to estimate mortality due to stroke, IHD, and T2DM attributable to high BMI. Results Obesity in adult females increased 1.54-fold from 12.0% (uncertainty interval [UI]: 11.5-12.4) to 18.5% (17.9-19.0), whereas in adult males, obesity nearly doubled from 4.5 (4.3-4.8) to 8.8 (8.5-9.2). In children, obesity more than doubled in both sexes, and overweight increased by 27.4% in girls and by 37.4% in boys. Mean BMI increased by 0.7 from 22.4 (21.6-23.1) to 23.1 (22.3-24.0) in adult males, and by 1.0 from 23.8 (22.9-24.7) to 24.8 (23.8-25.8) in adult females. South Africa 44.7 (42.5-46.8), Swaziland 33.9 (31.7-36.0) and Lesotho 31.6 (29.8-33.5) had the highest prevalence of obesity in 2019. The corresponding prevalence in males for the three countries were 19.1 (17.5-20.7), 19.3 (17.7-20.8), and 9.2 (8.4-10.1), respectively. The DRC and Madagascar had the least prevalence of adult obesity, from 5.6 (4.8-6.4) and 7.0 (6.1-7.9), respectively in females in 2019, and in males from 4.9 (4.3-5.4) in the DRC to 3.9 (3.4-4.4) in Madagascar. Conclusions The prevalence of high BMI is high in SADC. Obesity more than doubled in adults and nearly doubled in children. The 2019 mean BMI for adult females in seven countries exceeded 25 kg/m2. SADC countries are unlikely to meet UN2030 SDG targets. Prevalence of high BMI should be studied locally to help reduce morbidity.