Age-Specific Associations of Moderate-to-Vigorous Physical Activity With Relative and Absolute Risk of Type 2 Diabetes in UK Biobank Participants.
AIMS We assessed the age-specific associations between moderate-to-vigorous physical activity (MVPA) and incident type 2 diabetes. MATERIALS AND METHODS We included UK Biobank participants with valid accelerometry data without diabetes mellitus at baseline (N = 87 975; 62.7 years [IQR, 55.6-67.9]; 57% women). We examined whether age, sex and baseline metabolic disease status modified the associations of MVPA volume (lower versus higher) and, in exploratory analyses, MVPA timing (later-day versus earlier-day) with incident type 2 diabetes. Age-specific relative and absolute associations were assessed across 5-year age bins using hazard ratios (HRs) and incidence rate differences (IRDs), and additionally stratified by sex and baseline metabolic disease status. RESULTS Associations of MVPA volume with type 2 diabetes were most consistently modified by age, baseline prediabetes (all p-values for interaction < 0.05), with stronger associations observed among participants younger than the median population age (< 62.7 years, HR = 2.44 [95% CI: 2.05-2.90] versus HR = 1.65 [95% CI: 1.47-1.86]) and participants without prediabetes. Across 5-year age groups, HRs declined with age, whereas IRDs increased in the overall population. No clear effect modification was observed for the association between MVPA timing and type 2 diabetes risk. CONCLUSIONS The relative association between higher MVPA volume and lower type 2 diabetes risk attenuated with age and was weaker among individuals with prediabetes, whereas absolute risk reductions were larger among older and metabolically higher-risk individuals. These findings support considering both relative and absolute measures when targeting MVPA interventions for type 2 diabetes prevention.