Quality of life predicting long-term outcomes in cardiac resynchronization therapy patients

Aims: While improvement in quality of life (QoL) has been widely reported in cardiac resynchronization therapy (CRT) patients, its predictive value is not well-understood. We aimed to assess the predictive role of baseline QoL on long-term heart failure (HF) or death events in mild HF patients enrolled in Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy (MADIT-CRT). Methods and results: A total of 1791 of 1820 patients had their QoL evaluated at baseline, using the EuroQol-5 dimensions (EQ-5D) and the Kansas City Cardiomyopathy Questionnaires (KCCQ). Kaplan-Meier survival analyses and multivariate Cox models were utilized. Issues within any of the domains of the baseline EQ-5D questionnaire (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression) were associated with long-term mortality (median follow-up 5.6 years) (all P < 0.05). Heart failure or death events were predicted by issues in baseline mobility [hazard ratio (HR) = 1.41, P < 0.001], usual activities (HR = 1.41, P < 0.001), and anxiety/depression (HR = 1.21, P = 0.035). The risk of HF events alone was significantly higher in patients with baseline mobility issues (HR = 1.42, P < 0.001) or usual activity (HR = 1.35, P = 0.003). Every 10% increase in the visual analogue scale (0-100) was associated with an 8% lower risk of all-cause mortality (P = 0.006), and a 6% lower risk of HF/death (P = 0.002). Mobility issues also predicted echocardiographic reverse remodelling (-33.08 mL vs. -31.17 mL, P = 0.043). Using the KCCQ, patients in the lower tertile of the clinical summary or physical limitations score had a significantly higher risk of long-term HF or death (P < 0.05). Conclusion: In mild HF patients enrolled in MADIT-CRT, multiple baseline QoL questionnaire domains were predictors of echocardiographic remodelling, long-term all-cause mortality, and HF events.