Device-measured vigorous intermittent lifestyle physical activity and major cardiovascular events

ImportanceVigorous physical activity is a time-efficient and potent preventive intervention for major adverse cardiovascular events (MACE), although longer traditional exercise sessions are unappealing or inaccessible to most adults. ObjectiveWe examined the dose-response associations of device-measured vigorous intermittent lifestyle physical activity (VILPA, brief sporadic bouts of higher intensity occurring during daily living) with MACE and its sub-types in women and men. We also undertook analogous analyses in a sample of exercisers. Design, Setting, and ParticipantsProspective cohort analysis of 13,018 women and 9,350 men non-exercisers from the UK Biobank accelerometry sub-study; the contextual analyses involved 34,364 female/24,284 male exercisers from the same sub-study. ExposuresWrist accelerometer assessed daily VILPA duration of bouts lasting up to 1 and up to 2 minutes. Outcomes and MeasuresOverall and sex-specific dose-response associations of daily VILPA with MACE and its subtypes (incident myocardial infarction, heart failure and stroke). ResultsAmong female/male non-exercisers there were 331/488 all-MACE events (129/250 myocardial infarction, 96/119 heart failure,106/119 stroke events) over a mean 7.9-year follow-up. Daily VILPA duration exhibited a near-linear dose-response association with all MACE, myocardial infarction, and heart failure in women but not in men. Compared to women with no VILPA, the median daily VILPA duration of 3.4 minutes per day was associated with HRs of 0.55 (0.41, 0.75) for all MACE; and 0.33 (0.18, 0.59) for heart failure. Womens minimum doses (the dose associated with 50% of the optimal risk reduction) of 1.2-1.6 minutes of VILPA per day were associated with HRs of 0.70 (0.58, 0.86) for all-MACE, 0.67 (0.50, 0.91) for myocardial infarction and 0.60 (0.45, 0.81) for heart failure, respectively. The equivalent analyses in exercisers in the UK Biobank showed comparable beneficial associations of vigorous intensity activity with all MACE, myocardial infarction and heart failure in both sex groups. Conclusions and RelevanceAmongst non-exercisers, small amounts of VILPA were associated with substantially lower risk of myocardial infarction and heart failure in women but not in men. No such sex differences were evident among exercisers. VILPA may be a promising physical activity target for CVD prevention in women not willing or able to exercise.