Walking pace improves all-cause and cardiovascular mortality risk prediction: A UK Biobank prognostic study

Abstract

Aims The purpose of this study was to quantify and rank the prognostic relevance of dietary, physical activity and physical function factors in predicting all-cause and cardiovascular mortality in comparison with the established risk factors included in the European Society of Cardiology Systematic COronary Risk Evaluation (SCORE). Methods We examined the predictive discrimination of lifestyle measures using C-index and R2 in sex-stratified analyses adjusted for: model 1, age; model 2, SCORE variables (age, smoking status, systolic blood pressure, total and high-density lipoprotein cholesterol). Results The sample comprised 298,829 adults (median age, 57 years; 53.5% women) from the UK Biobank free from cancer and cardiovascular disease at baseline. Over a median follow-up of 6.9 years, there were 2174 and 3522 all–cause and 286 and 796 cardiovascular deaths in women and men, respectively. When added to model 1, self-reported walking pace improved C-index in women and men by 0.013 (99% CI: 0.007–0.020) and 0.022 (0.017–0.028) respectively for all-cause mortality; and by 0.023 (0.005–0.042) and 0.034 (0.020–0.048) respectively for cardiovascular mortality. When added to model 2, corresponding values for women and men were: 0.008 (0.003–0.012) and 0.013 (0.009–0.017) for all-cause mortality; and 0.012 (–0.001–0.025) and 0.024 (0.013–0.035) for cardiovascular mortality. Other lifestyle factors did not consistently improve discrimination across models and outcomes. The pattern of results for R2 mirrored those for C-index. Conclusion A simple self-reported measure of walking pace was the only lifestyle variable found to improve risk prediction for all-cause and cardiovascular mortality when added to established risk factors.