Meeting activity guidelines linked to 42% lower mortality

People with severe mental illness die earlier than the general population, and cardiovascular disease is a leading contributor to that gap. Physical activity is an obvious lever, but most evidence in this group relies on self-reported activity, which is notoriously imprecise — especially where medication, motivation and symptoms all affect movement. What has been missing is device-measured data with enough follow-up to link activity patterns to hard outcomes such as incident cardiovascular disease and death. This study asked whether there is a dose-response relationship, and whether the intensity of movement matters or simply the total volume.

The researchers analysed a prospective cohort of 6313 UK Biobank participants with severe mental illness who had accelerometry data collected between February 2013 and November 2021. Mean age was 61.05 years and 33.9% were men. Moderate-to-vigorous physical activity was split into two groups — under 150 and 150 or more minutes per week — following the World Health Organization guideline for adults, while total physical activity and light-intensity physical activity were divided into tertiles. Incident cardiovascular disease plus all-cause and cardiovascular mortality were ascertained through hospital and death registries, and these were the primary outcomes over a median follow-up of 7 years.

During follow-up, 868 participants developed incident cardiovascular disease, 233 died from any cause and 88 died from cardiovascular disease. Physical activity was inversely associated with all three outcomes. Meeting the guideline-recommended level of moderate-to-vigorous activity was associated with an 18% lower risk of incident cardiovascular disease (95% CI 0.68-0.99), a 42% lower risk of all-cause mortality (95% CI 0.43-0.79) and a 49% lower risk of cardiovascular mortality (95% CI 0.31-0.83). Combining recommended moderate-to-vigorous activity with moderate light-intensity activity was associated with the lowest risk overall, with reductions of 24%, 59% and 78% respectively — suggesting light movement contributes something beyond the vigorous minutes.

This extends the well-replicated activity-mortality relationship into a population that is usually under-represented in physical activity cohorts, and it does so with device-measured rather than self-reported movement. The finding that light activity adds benefit on top of guideline-level moderate-to-vigorous activity fits a broader emerging picture that total movement across the day matters, not only structured exercise. But this is observational, so the direction of causation is not established: undiagnosed illness, frailty or medication burden could reduce activity and independently raise mortality. The confidence interval for incident cardiovascular disease reaches close to 1, so that particular estimate is the least robust of the three.

For adults living with severe mental illness — and for those supporting them — this is a reason to think that reaching the standard activity guideline is associated with meaningfully better cardiovascular and survival outcomes, and that the association is at least as strong as in the general population. The pattern also suggests that time spent in gentle movement, not just brisk or hard effort, tracks with lower risk. Because this is an association from a single cohort, it cannot promise that adding activity will produce these exact reductions. It does, however, reinforce that movement is a plausible and low-cost part of protecting heart health in a group facing elevated risk.