This multi-cohort cross-sectional analysis compared complication profiles in African adults with type 2 diabetes who were lean (BMI <25 kg/m²) vs overweight/obese (BMI ≥25 kg/m²), using harmonised individual-level data from the AADM (n=2,790) and RODAM (n=541) cohorts across Ghana, Nigeria, and Kenya.
Lean adults had significantly higher prevalence of diabetic retinopathy (pPR 1.36 [95% CI 1.13–1.63]) and stroke (pPR 1.41 [95% CI 1.01–1.99]), but lower hypertension (pPR 0.77 [95% CI 0.71–0.85]) and 10-year CVD risk (pPR 0.85 [95% CI 0.74–0.97]) compared with overweight/obese peers; CKD prevalence did not differ. Body fat percentage mediated up to 92% of these differences.
- Cross-sectional design prevents causal inference or assessment of temporal sequence between phenotype and complications. - Stroke ascertainment relied on self-reported history without subtyping; CKD was defined by eGFR alone without albuminuria, potentially missing early microvascular kidney disease. - Residual confounding from unmeasured variables (medication adherence, healthcare access, true diabetes duration) cannot be excluded.
Nearly 40% of African adults with type 2 diabetes are lean and show a distinct complication pattern—more microvascular disease (retinopathy, stroke) but less hypertension and macrovascular risk—likely driven by insulin secretory failure rather than insulin resistance. Clinicians managing lean African patients with type 2 diabetes should be alert to this divergent risk profile and the potential inadequacy of insulin-sensitising agents alone.
