Mauritius Type 2 Diabetes Prevalence Falls to 19.9% in 2021 After Peak of 23.3% in 2009 via Repeated OGTT Surveys

Mauritius conducted seven nationally representative cross-sectional surveys from 1987 to 2021 using the WHO-recommended 2-hour OGTT in adults aged 20-74. Prevalence rose steadily from 14.7% overall in 1987 to a peak of 23.3% in 2009 before declining to 19.9% by 2021, with absolute reductions of 3.4 percentage points overall. The consistent protocol across surveys allows direct comparison unlike most national estimates that rely on fasting glucose or HbA1c alone.

The decline coincides with national NCD policy shifts including sugar taxation, school nutrition standards, and primary care screening programs initiated after 2009. These interventions addressed rising obesity and physical inactivity that had driven earlier increases. However, the observational design cannot isolate which measures produced the reversal or rule out concurrent economic or dietary changes.

Similar island nations in the Pacific show continued rises without equivalent long-term OGTT monitoring or policy responses. Mauritius data suggest early detection via OGTT plus upstream prevention may bend the curve where HbA1c-based surveillance often underestimates burden.

Next steps require replication of the full OGTT protocol in other high-burden settings and linkage of prevalence trends to individual-level exposure data to identify causal pathways.