The impact of lifestyle intervention on sedentary time in individuals at high risk of diabetes

Abstract

Aims/hypothesis The Diabetes Prevention Program (DPP) lifestyle intervention successfully achieved its goal of increasing leisure physical activity levels. This current study examines whether the lifestyle intervention also changed time spent being sedentary and the impact of sedentary time on diabetes development in this cohort. Methods 3232 DPP participants provided baseline data. Sedentary behaviour was assessed via an interviewer-administered questionnaire and reported as time spent watching television specifically (or combined with sitting at work). Mean change in sedentary time was examined using repeated measures ANCOVA. The relationship between sedentary time and diabetes incidence was determined using Cox proportional hazards models. Results During the DPP follow-up (mean: 3.2 years), sedentary time declined more in the lifestyle than the metformin or placebo participants (p <0.05). For the lifestyle group, the decrease in reported mean television watching time (22 [95% CI 26, 17] min/day) was greater than in the metformin or placebo groups (p< 0.001). Combining all participants together, there was a significantly increased risk of developing diabetes with increased television watching (3.5% per h spent watching television), after controlling for age, sex, treatment arm and leisure physical activity (p< 0.01), which was attenuated when time-dependent weight was added to the model. Conclusions/interpretation In the DPP, the lifestyle intervention was effective at reducing sedentary time, which was not a primary goal. In addition, in all treatment arms, individuals with lower levels of sedentary time had a significantly lower risk of developing diabetes. Future lifestyle intervention programmes should emphasise reducing television watching and other sedentary behaviours in addition to increasing physical activity. Trial registration ClinicalTrials.gov NCT00004992

Activity and Sedentary Time 10 Years After a Successful Lifestyle Intervention: The Diabetes Prevention Program

“…11,12 Questionnaires are well validated for measuring domain-specific behaviors and time spent in planned and higher-intensity activities, but not as accurate as accelerometers for assessing average time spent in all intensities of activity and sedentary behavior. 16–19 This new study objectively measured activity more than 10 years after DPP began in the majority of remaining DPPOS participants.…”

“…Therefore, it does not appear that the 37 minutes/day reduction in sedentary time reported for lifestyle participants over the DPP trial (mean, 3.2 years) was still evident more than 10 years later. 12 Had there been an explicit focus on reducing sedentary behavior in the DPP lifestyle intervention, the initial reductions in sedentary behavior may have been greater and perhaps lasted longer.…”

“…MAQ has been shown to be valid and reliable with strong correlations reported between leisure PA from MAQ and time spent in comparable bouts of MVPA from accelerometers (ρ=0.69–0.76, all p <0.0001). 12,15,31–33 Unreasonably high leisure PA values (>150 MET hours/week; <0.01% of all individual recordings) were truncated to 150 MET hours/week (450 minutes/week moderate activity).…”

“…11,12 After the DPP ended, participants from all study arms were offered a group-implemented version of the lifestyle intervention and have been followed as part of the DPP Outcomes Study (DPPOS) for more than 10 years since DPP baseline. 13 This extensive follow-up period made it possible to examine whether activity levels over the DPPOS follow-up increased from baseline and were greater than what would be expected in the general population.…”

“…4,6,8,11,12,14 Additionally, the majority of published studies rely solely on self-reported measures of PA. 4,6,8,11,12,14 Self-reported PA, using recall questionnaires, has been shown to be a reasonably valid and reliable method of assessing MVPA and domain-specific sedentary behaviors in adults. However, self-report has been shown to be less valid and reliable for measuring unplanned activities, light-intensity activity (LPA), and total accumulated sedentary behavior.…”