Cause-specific death and risk factors of one-year mortality after implantable cardioverter-defibrillator implantation: a nationwide study.

AIMS Current treatment guidelines recommend implantable cardioverter-defibrillators (ICDs) in eligible patients with an estimated survival beyond one year. There is still an unmet need to identify patients who are unlikely to benefit from an ICD.We determined cause-specific one-year mortality after ICD implantation and identified associated risk factors. METHODS AND RESULTS Using Danish nationwide registries (2000-2017), we identified 14,516 patients undergoing first-time ICD implantation for primary or secondary prevention. Risk factors associated with one-year mortality were evaluated using multivariable logistic regression. The median age was 66 years, 81.3% were male, and 50.3% received an ICD for secondary prevention. The one-year mortality rate was 4.8% (694/14,516). ICD recipients who died within one year were older and more comorbid compared to those who survived (72 vs. 66 years, p < 0.001). Risk factors associated with increased one-year mortality included dialysis (OR:3.26, CI:2.37-4.49), chronic renal disease (OR:2.14, CI:1.66-2.76), cancer (OR:1.51, CI:1.15-1.99), age 70-79 years (OR:1.65, CI:1.36-2.01), and age ≥80 years (OR:2.84, CI:2.15-3.77). The one-year mortality rates for the specific risk factors were: dialysis (13.8%), chronic renal disease (13.1%), cancer (8.5%), age 70-79 years (6.9%), and age ≥80 years (11.0%). Overall, the most common causes of mortality were related to cardiovascular diseases (62.5%), cancer (10.1%), and endocrine disorders (5.0%). However, the most common cause of death among patients with cancer was cancer-related (45.7%). CONCLUSION Among ICD recipients, mortality rates were low and could be indicative of relevant patient selection. Important risk factors of increased one-year mortality included dialysis, chronic renal disease, cancer, and advanced age.