LEISURE-TIME PHYSICAL ACTIVITY AND THE ONSET OF TYPE 2 DIABETES IN THE MALMÖ DIET AND CANCER STUDY COHORT

Sammanfattning: Aims/objectives: The study’s aim was to assess the association between different levels of leisure time physical activity (LTPA) and the risk of type 2 diabetes mellitus (T2DM) and assess the association between socio-economic status (SES) and distribution of LTPA. Methods: The study was based on the Malmo Diet and Cancer Study cohort that included participants aged 44-74 years at enrolment. Demographic and covariate data from the baseline questionnaire (1991-1996) and outcomes of interest (2014) linking the cohort data to various medical and population registers was used. LTPA was assessed using a standard questionnaire as a sum of products of 17 predefined individual activities (assessed as minutes spent weekly per activity in the previous year) with their intensity factors (Metabolic Equivalent or MET) and reported as MET-hours per week. Chi-square test was used to assess the proportions of different socioeconomic groups in the various LTPA categories and Cox regression utilized to model the association between LTPA and incidence of T2DM, adjusted for age, sex, body mass index (BMI), smoking, education level and occupation. Results: There were significant differences in the distribution of LTPA levels across the different socioeconomic groups. Moderate LTPA (7.5-15 MET-hours/week) was not significantly associated with T2DM risk (HR=0.92, 95% CI 0.81-1.05), vigorous (15-25 MET-hours/week) and strenuous (25-50 MET-hours/week) levels of LTPA were associated with reduced incidence of T2DM (HR=0.83, 95% CI 0.74-0.94) and (HR=0.81,95% CI 0.72-0.91) respectively. LTPA beyond 50 MET-hours/week had no added benefit (HR=0.84, 95% CI 0.74-0.96). Conclusion: The study demonstrated the benefits of different LTPA levels in reducing the risk of T2DM in the MDC cohort. Moderate activity was not significantly associated while vigorous activity and above was significantly associated with reduced risk but there was no added benefit for LTPA beyond 50 MET-hours per week. The amount of LTPA was significantly related to SES.