RESUMEN
Background The effect of adherence to cardiac rehabilitation (CR) on outcome is not clear. Therefore, we aimed to assess the impact of drop-out for non-medical reasons of CR on event-free survival in coronary artery disease (CAD). Methods A total of 876 patients who attended CR after acute coronary syndrome (ACS), percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) were included. Drop-out was defined as attending ≤50% of the training sessions. A combined endpoint of all-cause mortality and rehospitalization for a cardiovascular event was used to specify event-free survival. Differences in clinical characteristics were assessed and parameters with p < 0.10 were entered in a multiple Cox regression analysis. Results A total of 15% died or had a cardiovascular event during a median follow-up period of 33 months (interquartile range 24, 51). Overall, 17% dropped out before finishing half of the program. Patients who withdrew prematurely had a risk twice as high for a cardiovascular event or death (hazard ratio 1.92, 95% confidence interval 1.28-2.90) than those who attended more than half of the sessions. Both ACS (2.36, 1.47-3.58) and PCI (2.20, 1.22-3.96), as primary indicators for CR, were associated with an adverse outcome and also a prior history of chronic heart failure (CHF) remained negatively associated with event-free survival (3.67, 1.24-10.91). Finally, the presence of hyperlipidemia was independently related to a worse outcome (1.48, 1.02-2.16). Conclusions Drop-out for non-medical reasons was independently associated with a negative outcome in CAD. Therefore, underlying factors for drop-out should gain more attention in future research and should be taken into account when organizing CR.