Diabetes mellitus (DM) is an important comorbidity in an ageing population. Age, male sex, and obesity are risk factors for DM, and obesity is particularly common in people of African ancestry. We explored the associations between obesity, age and DM in the GEN-AFRICA cohort comprising African people with HIV in the United Kingdom.
Cross sectional study of African women and men with HIV aged >18 years who were enrolled between May 2018 and February 2020. BMI was classified as normal (18.5-24.9), pre-obese (25-29.9), or obese (>30 kg/m[sup]2[/sup]). Associations between demographic factors including age (<40, 40-50, >50 years), HIV parameters (AIDS, time since diagnosis, use of ART, nadir/current CD4, HIV viral load), obesity (BMI >30 kg/m[sup]2[/sup]), hypertension and DM (clinical diagnoses), and kidney disease (eGFR and proteinuria) were evaluated using logistic regression. Variables with p<0.1 in univariable analysis were included in multivariable models. Models were a priori stratified by gender.
A total of 2308 participants were included (mean age 48.0 [SD 9.9] years, 63% female, 99% on ART, median CD4 cell count 556 [IQR 409-721]/µL, 94% VL <200 c/mL); 36% were pre-obese and 44% obese, and 9.4% had DM (99% Type 2). Obesity was more common (52% vs. 31%, p<0.001) in female participants while DM was more prevalent (7.4% vs. 12.8%, p<0.001) in male participants; the prevalence of obesity and DM increased with age in both sexes (p<0.001). In univariable analysis, DM was associated with obesity as well as age (and hypertension, renal impairment, and proteinuria) in both female and male participants. After adjustment, age remained associated with DM whereas the association between obesity and DM was no longer significant (Table). Similar results were obtained when BMI was analysed in three strata, with normal BMI as referent (adjusted odds ratio 1.53 [0.74-3.18] for obese female, and 1.62 [0.90-2.90] for obese male participants).
Obesity is highly prevalent in this cohort of African people with well controlled HIV. The association between obesity and DM was attenuated in the multivariable models and no longer statistically significant. In both female and male participants, age >50 years was the strongest predictor of DM, and this group should be regularly screened for DM. Measures of central adiposity may be more useful predictors of DM in this population, especially in African women with HIV.