Higher levels of self-reported sitting time is associated with higher risk of type 2 diabetes independent of physical activity in Chile

Background: Sitting behaviours have increased markedly during the last two decades in Chile. However, their associations with health outcomes such as diabetes have not been reported. Therefore, the aim of this study was to investigate the independent association of self-reported sitting time with diabetes-related markers and diabetes prevalence in Chile. Methods: This cross-sectional study included participants (aged ≥18 years) from the Chilean National Health Survey 2009-10 (n = 4457). Fasting glucose and haemoglobin A1c (HbA1c) were measured by standardized protocols. The prevalence of type 2 diabetes (T2D) was determined using WHO criteria. Physical activity (PA) and time spent sitting were determined using the Global Physical Activity Questionnaire (GPAQ). Results: The odds ratio for T2D was 1.10 [95% CI: 1.04-1.16, P = 0.002] and 1.08 [1.02-1.14, P = 0.002] per 1 h increase in sitting time in men and women, respectively, independent of age, education, smoking, BMI and total PA. Overall, prevalence of T2D was 10.2 and 17.2% in individuals classified in the lowest and highest categories of sitting time, respectively. No significant associations were found between sitting time and glucose or HbA1c. Conclusions: Sitting time is positively associated with diabetes risk, independent of socio-demographic, obesity and PA levels, in the Chilean population.