Association of a multiple risk factor assessment and intervention program with risk of diabetes: A population-based matched cohort study

Background Type 2 diabetes incidence remains high among older adults and contributes substantially to morbidity and healthcare burden. Most evidence supporting diabetes prevention derives from intensive lifestyle interventions targeting high-risk individuals under controlled trial conditions. The effectiveness of low-intensity, population-based prevention programs embedded in routine care remains uncertain. We evaluated whether participation in a comprehensive health assessment and counseling program was associated with reduced incidence of diabetes in older adults. Methods and findings We conducted a population-based matched cohort study including 70-year-old residents of Umeå municipality, Sweden, enrolled between 2012 and 2022 and followed through December 2022. The intervention consisted of a comprehensive health assessment followed by individualized motivational counseling, without structured long-term follow-up. Participants were matched 1:10 to controls from the general Swedish population by birth year, sex, and educational level. Individuals with prevalent diabetes were excluded. The primary outcome was incident diabetes, defined as a first recorded diagnosis in specialist care and/or first dispensed glucose-lowering medication, identified through nationwide health and prescription registers. In total, 6,018 participants and 57,543 matched controls were included. During a mean follow-up of 4.9 years (standard deviation 2.9) in the intervention cohort and 4.8 years (standard deviation 2.9) in the control cohort, diabetes occurred in 335 (5.6%) participants and 3,919 (6.8%) controls. Participation was associated with a lower risk of incident diabetes (adjusted hazard ratio 0.76; 95% confidence interval [0.68,0.85]; p < 0.001). The association remained stable over time. The absolute risk reduction was 1.46 percentage points (95% confidence interval [0.91,1.98]; p < 0.001) at 5 years and 3.42 percentage points (95% confidence interval [2.13,4.75]; p < 0.001) at 10 years. Results were broadly consistent across the examined subgroups. The observational study design limits certainty regarding the intervention’s role in the observed association, and voluntary participation in the program may have introduced selection bias, healthy-volunteer effect, and residual confounding. Conclusions In this population-based cohort study, participation in a low-intensity preventive health program delivered in routine care was associated with a lower incidence of diabetes among older adults. However, the observational study design limits evidence on the intervention’s role in the observed association, and more robust evidence is needed. Nevertheless, these findings suggest that scalable, population-wide prevention strategies may complement intensive high-risk approaches in addressing diabetes in aging populations.