Accelerometer-measured sedentary time and physical activity-A 15 year follow-up of mortality in a Swedish population-based cohort

J Sci Med Sport. 2018 Jul;21(7):702-707. doi: 10.1016/j.jsams.2017.10.035. Epub 2017 Nov 7.


Objectives: To investigate the associations of objectively assessed sedentary time, light intensity physical activity (PA), moderate to vigorous intensity PA (MVPA), and total PA with all-cause mortality and mortality from cardiovascular disease (CVD) or cancer in a Swedish population-based cohort with 15 years follow-up time.

Design: Longitudinal prospective cohort study.

Methods: Data from 851 persons (56% women) ≥35 years at baseline were included. Primary exposure variables were time (min/day) spent sedentary, in light intensity PA and in MVPA, and total counts from an Actigraph 7164 accelerometer. Data on all-cause mortality and mortality from CVD or cancer were obtained from Swedish registers. Cox proportional hazards models estimated hazard ratios (HR) of mortality with 95% confidence intervals (CI).

Results: Compared with the least sedentary participants, those in the most sedentary tertile had an increased risk of all-cause mortality, HR: 2.7 (1.4, 5.3), CVD mortality, HR: 5.5 (1.4, 21.2) and cancer mortality, HR: 4.3 (1.2, 16.0). For all-cause mortality, those in the highest light intensity PA tertile had a HR 0.34 (0.17, 0.67) compared with the lowest tertile. A similar pattern was found for CVD and cancer mortality. More time spent in MVPA was associated with the largest risk reduction for CVD mortality, with an almost 90% lower risk in the tertile with the most time in MVPA.

Conclusions: This study confirms a strong inverse relationship between MVPA and mortality, and adds new insight for the understanding of the associations between sedentary time and light intensity PA and mortality.

Keywords: Accelerometry; Epidemiology; Mortality; Physical activity; Prospective; Sedentary behaviour.

MeSH terms

  • Accelerometry
  • Aged
  • Cardiovascular Diseases / mortality*
  • Exercise*
  • Female
  • Follow-Up Studies
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Mortality*
  • Neoplasms / mortality*
  • Proportional Hazards Models
  • Prospective Studies
  • Risk Factors
  • Sedentary Behavior*
  • Sweden
  • Time Factors