Fifteen-year mortality and prognostic factors in patients with dilated cardiomyopathy: persistent standardized application of drug therapy and strengthened management may bring about encouraging change in an aging society.

Abstract

BACKGROUNDThere is scarce data on the long-term mortality and associated prognostic factors in patients with dilated cardiomyopathy (DCM). The study aimed to investigate the all-cause mortality up to 15 years (mean 7.9 ± 5.7 years) in such patients, and the independent prognostic factors influencing their long-term mortality.METHODSOne hundred and sixty-six consecutive patients with DCM were prospectively enrolled from 2002 to 2003. The mean age of patients was 59.5 ± 10.4 years, and approximately 57% were male. They were followed up by telephone or outpatient visit at least every three months until 2019 or all-cause death occurred. Predictors of mortality were identified using multivariate logistic regression analysis.RESULTSDuring the 15 years of follow-up, five patients were lost to follow-up, and the complete data records of 161 patients were included in the analysis. Patients were treated with angiotensin-converting-enzyme inhibitors (ACEI) or angiotensin-receptor blocker (ARB), β-blockers, mineralocorticoid receptor antagonist (MRA), diuretics and digitalis from 2002 to 2004, and maintained at the maximum tolerated doses between 2004 and 2019. Our safety targets to maintain heart rate and blood pressure at 60-80 beats/min and 90-120/60-80 mmHg, respectively. All-cause mortality in the first five years was 55.9%. The independent risk factors for the 5-year mortality were age ≥ 70 years old (OR = 5.45, P = 0.006), systolic blood pressure (SBP) > 120 mmHg (OR = 3.63, P = 0.004), 6-minute walk distance (6MWD) < 450 m (OR = 3.84, P = 0.001). 15-year all-cause mortality was 65.8%. The independent risk factors for 15-year mortality were age ≥ 70 years old (OR = 16.07, P = 0.009), LVEF ≤ 35% (OR = 5.69, P = 0.003), and SBP > 120 mmHg (OR = 9.56, P < 0.001). CONCLUSIONSThis study was the first to demonstrate the 15-year survival rate of 34% in DCM patients. The DCM patients’ first five-year all-cause mortality decreased significantly after continuous standardized treatment and intensive management. The mortality then plateaued in the following 10 years. Age ≥ 70 years, LVEF ≤ 35%, and SBP > 120 mmHg were independent predictors of 15-year all-cause mortality.