Are anxiety and depression risk factors for poor medication adherence in patients with an implantable cardioverter defibrillator?
Authors: Skov O , Johansen J B , Nielsen J C , Larroude C E , Riahi S , Melchior T M , Vinther M , Skovbakke S , Rottmann N , Pedersen S S 
Published: July 2023

Abstract

Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): TrygFonden
The Lundbeck Foundation
Patient@Home

Background
The implantable cardioverter defibrillator (ICD) is the preferred treatment for prevention of sudden cardiac death. Most patients with an ICD receive adjunctive medication to manage their heart disease. Poor medication adherence is a prognostic risk factor for cardiac patients and is linked to psychological factors, such as anxiety and depression. To our knowledge, no studies have examined if anxiety and/or depression at the time of ICD implantation is associated with medication adherence during the first year post-implantation. This information is important as it could help health care professionals identify and prevent poor medication adherence in ICD patients.

Purpose
To examine if anxiety and/or depression at ICD implantation are associated with medication adherence one-year post-implantation in ICD patients.

Methods
Secondary outcome analysis of the ACQUIRE-ICD, multisite, randomised controlled trial. Out of 478 patients with a first-time ICD or cardiac resynchronization therapy defibrillator (CRT-D) included in the trial, 433 patients (90.6%) took heart medication. Of these 433 patients, 322 patients (74.4%) were included in the analyses as they completed assessments at both baseline (implantation) and at 12 months post-implantation. Medication adherence was measured with the 8-item Morisky Medication Adherence Scale (MMAS), anxiety with Generalized Anxiety Disorder scale (GAD-7), and depression with Patient Health Questionnaire-9 (PHQ-9).

Results
The mean age of the participants was 60.2 ± 11.2, mainly male (83.9%). Medication adherence was generally medium to high at baseline [6.8% low adherence, 40.1% medium adherence, 53.1% high adherence, mean MMAS score: 7.31 ± 0.94), and at 12-months follow-up (8.1% low adherence, 37.3% medium adherence, 54.6% high adherence, mean MMAS score: 7.33 ± 0.93).
In univariate analyses, depression scores at baseline were significantly negatively associated with medication adherence at 12-months post-implantation while adjusting for baseline MMAS scores (B = -0.02, 95% CI [- 0.04, -0.00], p = .04). This association remained statistically significant in the multivariate analysis also adjusting for gender, intervention group, heart failure severity (NYHA class I-II versus III-IV), and implantation center (B = -0.03, 95% CI [- 0.05, -0.00], p = .02).
Anxiety scores at baseline were not significantly associated with medication adherence at 12-months post-implantation in neither the univariate (B = -0.02, 95% CI [- 0.04, 0.01], p = .14) nor adjusted analyses (B = -0.02, 95% CI [- 0.04, 0.00], p = .09).

Conclusion
Depression symptoms at the time of ICD implantation were associated with medication adherence at 12 months post-implantation with higher depression symptoms being associated with lower medication adherence. Anxiety symptoms were not predictive of medication adherence. Patients presenting with depressive symptoms at ICD implantation might be at risk for poor medication adherence.