Obesity in Botswana: time for new cut-off points for abdominal girth?

Country-specific cut-off points for defining central obesity in black Africans are long overdue.

Anthropometric data from 215 (51.4%) male and 203 (48.6%) female patients seen in Gaborone between 2005 and 2015 were analysed to establish appropriate cut-off points for waist circumference (WC) corresponding to a body mass index (BMI) of 30 kg/m². Relative risks for cardiometabolic disorders were calculated for different BMI and WC categories using MedCalc^®. The subjects' mean age was 50.0 ± 10.8 years and 80.6% were Batswana.

Only 7.2% of patients had a BMI < 25 kg/m², 27.3% were overweight and 65.5% were obese; mean BMI was 34.9 ± 6.5 kg/m² in the women versus 31.0 ± 4.9 kg/m² in the men (p < 0.0001). New cut-off points of 98 cm in men and 85 cm in women emerged. Different weight and WC categories appeared not to confer increased relative risk of hypertension, dysglycaemia or dyslipidaemia.

The proposed WC cut-off values, if validated, should set the pace for larger studies across sub-Saharan Africa.