Quantifying the Association Between Physical Activity and Cardiovascular Disease and Diabetes: A Systematic Review and Meta-Analysis

Background

The relationships between physical activity (
PA
) and both cardiovascular disease (
CVD
) and type 2 diabetes mellitus (T2
DM
) have predominantly been estimated using categorical measures of
PA
, masking the shape of the dose‐response relationship. In this systematic review and meta‐analysis, for the very first time we are able to derive a single continuous
PA
metric to compare the association between
PA
and
CVD
/T2
DM
, both before and after adjustment for a measure of body weight.



Methods and Results

The search was applied to
MEDLINE
and
EMBASE
electronic databases for all studies published from January 1981 to March 2014. A total of 36 studies (3 439 874 participants and 179 393 events, during an average follow‐up period of 12.3 years) were included in the analysis (33 pertaining to
CVD
and 3 to T2
DM
). An increase from being inactive to achieving recommended
PA
levels (150 minutes of moderate‐intensity aerobic activity per week) was associated with lower risk of
CVD
mortality by 23%,
CVD
incidence by 17%, and T2
DM
incidence by 26% (relative risk [
RR
], 0.77 [0.71–0.84]), (
RR
, 0.83 [0.77–0.89]), and (
RR
, 0.74 [0.72–0.77]), respectively, after adjustment for body weight.



Conclusions

By using a single continuous metric for
PA
levels, we were able to make a comparison of the effect of PA on
CVD
incidence and mortality including myocardial infarct (
MI
), stroke, and heart failure, as well as