Association of Combined Sedentary Behavior and Diabetes Mellitus with All-Cause Mortality in Brazilian Adults

Abstract

Diabetes mellitus (DM) is associated with increased specific and all-cause mortality in different populations. Although sedentary behavior (SB) has been identified as a modifiable risk factor for DM, cardiovascular disease, and all-cause mortality, investigations regarding the combined effect of DM and SB on all-cause mortality are scarce. PURPOSE: To investigate the combined effect of DM and SB on all-cause mortality in adults from the Brazilian National Health System (NHS). METHODS: Data were obtained from 970 adults (709 women; mean age 64.7 ± 9.1 years) enrolled in the Brazilian NHS from 2010-2016. Participants were 50 years or older, registered for at least one year in the NHS, and received at least one medical visit in the past six months. SB was estimated via self-reported TV viewing frequency on the Baecke questionnaire and was subsequently classified into thirds: low, middle, and high. For our analysis the low and middle groups were combined to indicate lower level of SB due to the small sample size. Presence of physician-diagnosed DM was assessed via medical record. Mortality was reported by participants’ relatives and confirmed via medical records of the Brazilian NHS. Cox regression determined hazard ratios (HRs) and its 95% confidence intervals (95%CIs). Reference group was lower SB without DM at baseline (health status, sociodemographic and behavioural covariates were potential confounders). RESULTS: In overall sample, 276 (28%) had DM, 210 (21.6%) had high SB, and 62 (6.4%) had both DM and high SB at baseline (89 deaths were registered). In the adjusted model, the combination of DM and high SB was associated with greater risk of all-cause mortality (HR: 3.38; 95%CI = 1.86-6.13) compared to those without DM who also did not have high SB at baseline. The presence of DM (HR: 1.33; 95%CI = 0.76-2.34) or high SB alone (HR: 1.16; 95%CI = 0.62-2.17) were not significantly different from referent group. CONCLUSION: In this sample, the combination of both DM and high SB (but not DM and SB alone) had more than three times greater risk for all-cause mortality compared to those without DM and high SB. Supported by São Paulo Research Foundation (FAPESP) Grant 2015/17777-3 and 2016/11140-6.