Association between accelerometer-derived physical activity and incident cardiac arrest

Aims Studies on objectively measured physical activity (PA) have investigated acute cardiovascular outcomes but not cardiac arrest (CA). Our study aimed to investigate the dose-response relationship between accelerometer-measured PA and CA by intensity of PA.Methods and results This prospective cohort study included 98 893 UK Biobank participants whose PA data were measured using wrist-worn accelerometers. Total PA volume was measured using the average overall acceleration. Minutes per week of light PA (LPA), moderate PA (MPA), and vigorous PA (VPA) were recorded. The incident CA was identified using diagnostic codes linked to hospital encounters and death records. Cox proportional hazard models with restricted cubic splines were used to study the associations, including sex differences. During the follow-up period (median: 7.31 years; interquartile range: 6.78-7.82 years), 282 incident CAs (0.39 per 1000 person-years) occurred. Total PA was inversely related to CA risk. The CA risk decreased sharply until the time spent in MPA or VPA reached similar to 360 min or 20 min per week, respectively, after which it was relatively flat. The LPA was not associated with CA risk. Subgroup analyses showed a more pronounced association between PA and a reduced risk of CA in women compared to men.Conclusion Accelerometer-measured PA, particularly MPA and VPA, was associated with a lower CA risk. Furthermore, a stronger association was observed in women than men. Graphical Abstract