Background: Life stresses and negative emotions, such as anxiety and depression, are associated with adverse cardiac events, including arrhythmia. Patients undergoing implantation of an automatic internal cardioverter defibrillator provide a unique opportunity to characterize these relationships since all tachyarrhythmia episodes are recorded by the device.
Objectives: The purpose of this study was to examine the association of emotional status after internal cardioverter defibrillator (ICD) implantation and subsequent arrhythmia events.
Methods: An analysis of data obtained in a prospective longitudinal study of responses to the ICD measured mood disturbance (Profile of Mood States; POMS) before implant and at 1, 3, 6, and 9 months postoperatively. Subjects included 144 men and 32 women with a mean age of 60 ± 13 years and a mean left ventricular ejection fraction (LVEF) of 33 ± 12%. Arrhythmia events were measured by selfreport of shocks and by ICD device interrogation to obtain the number and type (defibrillation, cardioversion, and antitachycardia pacing) of therapies delivered by the ICD. For each time point, POMS scores of subjects who had arrhythmia events were compared with those who did not. For subjects who had ICD shocks, pre-event and post-event POMS scores were also compared. Multiple logistic regression was used at each time point to determine if clinical, demographic and psychological data could predict arrhythmia events.
Results: Patients with arrhythmia events had higher POMS scores throughout the 9 months of follow-up. Higher level of mood disturbance (specifically anxiety, fatigue, and confusion) at 1 and 3 months were independent predictors of subsequent arrhythmia events at 3 and 6 months after controlling for LVEF, the presence of coronary artery disease, pre-implant arrhythmia history, and the use of amiodarone and beta-blocking agents. There were no differences in POMS scores before and after ICD shocks, reinforcing the notion that negative emotions were a cause, rather than a consequence, of arrhythmia events.
Conclusions: Mood disturbances, such as anxiety, may increase the risk for arrhythmia events after ICD insertion. Depression and Anxiety 9: 163-168, 1999.