Impact of mitigating obesity, smoking, and physical inactivity on type 2 diabetes mellitus burden in Oman: insights from mathematical modeling.

Introduction: To estimate the impact of reducing obesity, smoking, and physical inactivity (PIA) prevalence, and of introducing physical activity (PA) as an explicit intervention, on the prevalence, incidence, and mortality of type 2 diabetes mellitus (T2DM) in Oman.

Research design and methods: A deterministic population-level mathematical model was employed to investigate the impact of different scenarios for reducing T2DM risk factors on T2DM epidemiology. The model was stratified by sex, age group, risk factor status, T2DM status, and intervention status and parameterized with nationally representative data. Intervention scenarios were calculated and compared with a baseline (no-intervention) scenario for changes in T2DM prevalence, incidence, and mortality among adult Omanis between 2020 and 2050.

Results: In the no-intervention scenario, T2DM prevalence increased from 15.2% in 2020 to 23.8% in 2050. Achieving the goals of halting the rise of obesity, reducing smoking by 30%, and reducing PIA by 10% as outlined in the WHO's Global Action Plan for Non-communicable Diseases (implemented between 2020 and 2030 and then maintained between 2031 and 2050) would reduce T2DM prevalence by 32.2%, cumulative incidence by 31.3%, and related deaths by 19.3% by 2050. Halting the rise of or reducing obesity prevalence by 10%-50% would reduce T2DM prevalence by 33.0%-51.3%, cumulative incidence by 31.9%-53.0%, and related deaths by 19.5%-35.6%. Reducing smoking or PIA prevalence by 10%-50% would lead to smaller reductions of less than 5% in T2DM prevalence, cumulative incidence, and related deaths. Introducing PA with varying intensities at a 25% coverage would reduce T2DM prevalence by 4.9%-14.1%, cumulative incidence by 4.8%-13.8%, and related deaths by 3.4%-9.6% by 2050.

Conclusions: Intervention-for-prevention efforts targeting obesity reduction and introducing PA could result in major reductions in the T2DM burden. Prioritizing such interventions could alleviate the burden of T2DM in Oman and other countries with similarly high T2DM and obesity burdens.