Association Between Out-of-Hospital Falls and Cardiovascular Events in Patients with Coronary Heart Disease: A Retrospective Cohort Study

Background Falls are increasingly recognized as adverse events in coronary heart disease (CHD) patients, yet their prognostic implications remain incompletely understood. This study examined the independent associations of falls with mortality and major adverse cardiovascular events, and the roles of functional status and frailty in these relationships. Methods This retrospective cohort study enrolled 2,139 CHD patients with median follow-up of 36 months. Falls were ascertained via telephone interviews every 3 months. Primary outcomes included major adverse cardiovascular events (MACE) and major adverse cardiovascular and cerebrovascular events (MACCE). Secondary outcomes comprised all-cause and cardiac mortality. Multivariable Cox models with stepwise adjustment for functional status indicators were constructed, with subgroup analyses stratified by frailty status. Results During follow-up, 171 patients (8.0%) experienced falls. Falls were associated with mortality in univariate analysis but not after adjusting for functional status, indicating mediation by functional decline. In contrast, falls remained independently associated with MACE (HR=1.73, 95%CI: 1.17-2.57, P=0.006) and MACCE (HR=1.67, 95%CI: 1.14-2.46, P=0.009) in fully adjusted models. Frailty significantly modified this association (P for interaction <0.001). Among robust patients, falls conferred substantially elevated risk (MACE: HR=4.08, 95%CI: 2.37-7.01; MACCE: HR=3.94, 95%CI: 2.30-6.76), whereas no significant association was observed in pre-frail or frail patients. Conclusions Falls independently predict long-term MACE and MACCE in CHD patients, with mortality effects mediated by functional status. Frailty significantly modifies the fall-cardiovascular event relationship--robust patients experiencing falls face substantially elevated cardiovascular risk and warrant comprehensive evaluation. These findings support integrating fall history into cardiovascular risk assessment and implementing frailty-stratified management.