Less physical activity increases mortality risk
Patients who were the least physically active had an increased risk for all-cause and CVD mortality, according to a study published in the Journal of the American College of Cardiology.
Those who reported moderate to vigorous physical activity based on current recommendations lessened or eliminated this association, according to the study.
“Our results support continued efforts to promote physical activity in those segments of the population that sit a lot for whatever reason,” Emmanuel Stamatakis, PhD, professor of physical activity, lifestyle and population health at the University of Sydney, said in a press release. “In the absence of some physical activity, merely reducing sitting times may be insufficient for better health.”
Researchers analyzed data from 149,077 participants (59% younger than 60 years; 56% women) from the 45 and Up Study. Participants completed questionnaires to collect information on sitting, standing and sleeping variables, in addition to levels of physical activity.
Follow-up was conducted for a median of 8.9 years for all-cause mortality and 7.4 years for CVD mortality. During follow-up, there were 8,689 deaths, 1,644 of which were related to CVD.
The interaction between sitting and moderate to vigorous physical activity was statistically significant for all-cause mortality (P < .001), although this was not seen for CVD mortality (P = .478). The HR for all-cause mortality when comparing participants with the most sedentary time with those with the least sedentary time in the group who reported no moderate to vigorous physical activity was 1.52 (95% CI, 1.13-2.03).
There was weak or inconsistent evidence for the risk for all-cause and CVD mortality in participants with more sitting time and who reported either lower or upper limits of moderate to vigorous physical activity.
Participants who sat for more than 6 hours per day had a stronger association between replacing sitting with walking and moderate to vigorous physical activity. Each hour of sitting that was replaced with vigorous activity was associated with an HR of 0.36 (95% CI, 0.17-0.74).
“Reduction of sitting time is an important strategy, ancillary to increasing physical activity, for preventing cardiovascular disease and premature mortality in physically inactive populations,” Stamatakis and colleagues wrote.
“Given that sedentary behaviors appear to be vastly outcompeting more healthy physical activity behaviors during our discretionary time, it is more important than ever to attend to our daily physical activity and sitting time and to try to optimize both behaviors for better health,” Charles E. Matthews, PhD, senior investigator in the metabolic epidemiology branch of the division of cancer epidemiology and genetics at the National Cancer Institute in Rockville, Maryland, wrote in a related editorial. “To this end, the report from Stamatakis [and colleagues] provides new and actionable insights for translating their findings to clinical and public health practice.” – by Darlene Dobkowski
Disclosure s : Stamatakis reports he received support from PAL Technologies. Matthews reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.