Appropriate Shocks and Mortality in Patients With Versus Without Diabetes With Prophylactic Implantable Cardioverter Defibrillators

Abstract

OBJECTIVE Diabetes increases the risk of all-cause mortality and sudden cardiac death (SCD). The exact mechanisms leading to sudden death in diabetes are not well known. We compared the incidence of appropriate shocks and mortality in patients with versus without diabetes with a prophylactic implantable cardioverter defibrillator (ICD) included in the retrospective EU-CERT-ICD registry. RESEARCH DESIGN AND METHODS AND RESULTS A total of 3,535 patients from 12 European EU-CERT-ICD centers with a mean age of 63.7 ± 11.2 years (82% males) at the time of ICD implantation were included in the analysis. A total of 995 patients (28%) had a history of diabetes. All patients had an ICD implanted for primary SCD prevention. End points were appropriate shock and all-cause mortality. Mean follow-up time was 3.2 ± 2.3 years. Diabetes was associated with a lower risk of appropriate shocks (adjusted hazard ratio [HR] 0.77 [95% CI 0.62–0.96], P = 0.02). However, patients with diabetes had significantly higher mortality (adjusted HR 1.30 [95% CI 1.11–1.53], P = 0.001). CONCLUSIONS All-cause mortality is higher in patients with diabetes than in patients without diabetes with primary prophylactic ICDs. Subsequently, patients with diabetes have a lower incidence of appropriate ICD shocks, indicating that the excess mortality might not be caused primarily by ventricular tachyarrhythmias. These findings suggest a limitation of the potential of prophylactic ICD therapy to improve survival in patients with diabetes with impaired left ventricular function.

Clinical effectiveness of primary prevention implantable cardioverter-defibrillators: results of the EU-CERT-ICD controlled multicentre cohort study

“…Our findings in diabetics agree well with a meta-analysis of 3345 retrospectively identified patients in the early landmark studies which confirmed that diabetics did not have a survival benefit, 21 as well as recent findings from the retrospective EU-CERT-ICD registry project in 3535 patients. 22 Importantly, our results concur with a substudy from DANISH 23 demonstrating that elderly patients ≥68 years did not experience ICD survival benefit. The overall group of the DANISH study ( n = 1116 patients) did not show a significant survival benefit (HR 0.87, 95% CI 0.68–1.12, P = 0.28) 7 which we do not consider contradicting our study findings.…”

Fragmented QRS is associated with ventricular arrhythmias in heart failure patients: A systematic review and meta‐analysis

“…Multiple studies have shown that age is not a contributing factor to VA in ICD patients (Santangelo et al, 2021), (Bergau et al, 2017), and we and others have found that comorbidities are not often associated with VA or appropriate ICD therapy (Engstrom et al, 2020). While some studies have demonstrated a link between diabetes and VA (Grisanti, 2018), others have reported the opposite (Juhani Junttila et al, 2020), which may be related to HF…”

“…Multiple studies have shown that age is not a contributing factor to VA in ICD patients (Santangelo et al, 2021 ), (Bergau et al, 2017 ), and we and others have found that comorbidities are not often associated with VA or appropriate ICD therapy (Engstrom et al, 2020 ). While some studies have demonstrated a link between diabetes and VA (Grisanti, 2018 ), others have reported the opposite (Juhani Junttila et al, 2020 ), which may be related to HF severity and the presence of different comorbidities. Further studies involving larger populations are required to clarify the relationship between age, diabetes, comorbidities, and VA in heart failure patients with and without fQRS.…”

Influence of diabetes on mortality and ICD therapies in ICD recipients: a systematic review and meta-analysis of 162,780 patients

“…Steiner et al showed that diabetes was not associated with an increased risk of appropriate or inappropriate ICD therapies [ 31 , 32 , 39 ]. However, Ruwald et al found that patients with diabetes had a 58% increased risk of appropriate therapy and a 46% decreased risk of inappropriate therapy [ 33 ] For ICD shock and ATP, the conclusions are also not consistent [ 15 , 24 , 33 , 39 ]. Our cumulative meta-analysis showed that diabetes ICD recipients do not have a higher risk of ICD therapies, including appropriate therapy, inappropriate therapy, appropriate shock, inappropriate shock and appropriate ATP, than nondiabetic ICD recipients.…”

“…This means that the higher mortality in diabetic ICD recipients is not caused by ventricular arrhythmias or ICD therapies. Therefore, a possible reason for the increased mortality in diabetes recipients may be the comorbidities related to diabetes, independent of the effects of ICD therapy [ 24 ]. Our study found that diabetes was associated with a reduced risk of inappropriate ATP.…”