Tabada, Grace H.

Background Variation in outcomes by race/ethnicity in adults with heart failure (HF) has been previously observed. Identifying factors contributing to these variations could help target interventions. We evaluated the association of race/ethnicity with HF outcomes and potentially contributing factors within a contemporary HF cohort. Methods and Results We identified members of Kaiser Permanente Northern California, a large integrated healthcare delivery system, who were diagnosed with HF between 2012 and 2016 and had at least 1 year of prior continuous membership and left ventricular ejection fraction data. We used Cox regression with time‐dependent covariates to evaluate the association of self‐identified race/ethnicity with HF or all‐cause hospitalization and all‐cause death, with backward selection for potential explanatory variables. Among 34 621 patients with HF, compared with White patients, Black patients had a higher rate of HF hospitalization (adjusted hazard ratio [HR], 1.28; 95% CI, 1.18–1.38) but a lower rate of death (adjusted HR, 0.78; 95% CI, 0.72–0.85). In contrast, Asian/Pacific Islander patients had similar rates of HF hospitalization, but lower rates of all‐cause hospitalization (adjusted HR, 0.89; 95% CI, 0.85–0.93) and death (adjusted HR, 0.75; 95% CI, 0.69–0.80). Hispanic patients also had a lower rate of death (adjusted HR, 0.85; 95% CI, 0.80–0.91). Sensitivity analyses showed that effect sizes for Black patients were larger among patients with reduced ejection fraction. Conclusions In a contemporary and diverse population with HF, Black patients experienced a higher rate of HF hospitalization and a lower rate of death compared with White patients. In contrast, selected outcomes for Asian/Pacific Islander and Hispanic patients were more favorable compared with White patients. The observed differences were not explained by measured potentially modifiable factors, including pharmacological treatment. Future research is needed to identify explanatory mechanisms underlying ongoing racial/ethnic variation to target potential interventions.

OBJECTIVE To determine whether burden of multiple chronic conditions (MCCs) influences the risk of receiving inappropriate vs appropriate device therapies. DESIGN Retrospective cohort study. SETTING Seven US healthcare delivery systems. PARTICIPANTS Adults with left ventricular systolic dysfunction receiving an implantable cardioverter‐defibrillator (ICD) for primary prevention. MEASUREMENTS Data on 24 comorbid conditions were captured from electronic health records and categorized into quartiles of comorbidity burden (0‐3, 4‐5, 6‐7 and 8‐16). Incidence of ICD therapies (shock and antitachycardia pacing [ATP] therapies), including appropriateness, was collected for 3 years after implantation. Outcomes included time to first ICD therapy, total ICD therapy burden, and risk of inappropriate vs appropriate ICD therapy. RESULTS Among 2235 patients (mean age = 69 ± 11 years, 75% men), the median number of comorbidities was 6 (interquartile range = 4‐8), with 98% having at least two comorbidities. During a mean 2.2 years of follow‐up, 18.3% of patients experienced at least one appropriate therapy and 9.9% experienced at least one inappropriate therapy. Higher comorbidity burden was associated with an increased risk of first inappropriate therapy (adjusted hazard ratio [HR] = 1.94 [95% confidence interval {CI} = 1.14‐3.31] for 4‐5 comorbidities; HR = 2.25 [95% CI = 1.25‐4.05] for 6‐7 comorbidities; and HR = 2.91 [95% CI = 1.54‐5.50] for 8‐16 comorbidities). Participants with 8‐16 comorbidities had a higher total burden of ICD therapy (adjusted relative risk [RR] = 2.12 [95% CI = 1.43‐3.16]), a higher burden of inappropriate therapy (RR = 3.39 [95% CI = 1.67‐6.86]), and a higher risk of receiving inappropriate vs appropriate therapy (RR = 1.74 [95% CI = 1.07‐2.82]). Comorbidity burden was not significantly associated with receipt of appropriate ICD therapies. Patterns were similar when separately examining shock or ATP therapies. CONCLUSIONS In primary prevention ICD recipients, MCC burden was independently associated with an increased risk of inappropriate but not appropriate device therapies. Comorbidity burden should be considered when engaging patients in shared decision making about ICD implantation.

Objective Patients with chronic kidney disease (CKD) have higher risk of sudden cardiac death; however, they may not receive implantable cardioverter defibrillators (ICDs), in part due to higher risk of complications. We evaluated whether CKD is associated with greater risk of device-delivered shocks/antitachycardia pacing (ATP) therapies among patients receiving a primary prevention ICD. Methods We studied participants in the observational Cardiovascular Research Network Longitudinal Study of Implantable Cardioverter Defibrillators. CKD was defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. Outcomes included all delivered shocks/ATPs therapies and type of shock/ATP therapies (inappropriate or appropriate, determined by physician adjudication) within the 3 years. We evaluated the associations between CKD and time to first device therapy, burden of device therapy, and inappropriate versus appropriate device therapy, adjusting for demographics, comorbidity, laboratory values and medication use. Results Among 2161 participants, 1066 (49.3%) had CKD (eGFR 44±11 mL/min/1.73 m2) at ICD implantation. During mean of 2.26±0.89 years, 9.8% and 18.5% of participants had at least one inappropriate and appropriate shock/ATP therapies, respectively. CKD was not associated with time to first shock/ATP therapies (adjusted HR 0.87, 95% CI 0.73 to 1.05), overall burden of shock/ATP therapies (adjusted relative rate 0.93, 95% CI 0.74 to 1.17) or inappropriate versus appropriate shock/ATP therapies (adjusted relative risk 0.88, 95% CI 0.68 to 1.14) compared with not having CKD. Conclusions In adults receiving a primary prevention ICD, mild-to-moderate CKD was not associated with the timing, burden or appropriateness of subsequent device therapy. Potential concern for inappropriate ICD-delivered therapies should not preclude ICDs among eligible patients with CKD.