Antidepressants and the risk of arrhythmia in elderly affected by a previous cardiovascular disease: a real-life investigation from Italy

The cardiovascular safety of tricyclic antidepressants in overdose and in clinical use

Tricyclic antidepressants (TCAs) remain widely prescribed for depression and many other conditions. There may be important differences between individual TCA in regard to their overdose toxicity and their cardiac toxicity in clinical use. We conducted a systematic review to compare the toxicity of individual TCA in overdose and the risk of serious adverse cardiac events occurring with therapeutic doses. We used the fatal toxicity index (FTI) and case fatality ratio as markers of fatality in overdose, and hazard ratios or odds ratios for the risk of cardiovascular adverse events during normal clinical use. In all, 30 reports of mortality in overdose and 14 observational studies assessing the risk of cardiovascular adverse events in clinical use were included. FTI values were of the same order of magnitude (101-102) for all TCAs except lofepramine. Desipramine appears to be somewhat more likely than other TCAs to lead to death in overdose. Amitriptyline, clomipramine, dothiepin/dosulepin, doxepin, trimipramine and imipramine showed broadly similar toxicity and were usually reported to be less toxic than desipramine. Data on nortriptyline were contradictory. Lofepramine had the lowest risk of death in overdose. The rank order of overdose toxicity was broadly consistent between different FTI definitions and between markers used. With respect to the risk of cardiovascular events at clinically relevant exposure, amitriptyline, nortriptyline and lofepramine were associated with a greater risk of in-use cardiotoxicity. All measures of overdose toxicity were subject to external influences and confounding. The continued use of TCAs in depression and other conditions should be minimized when considering their undoubted toxicity in overdose and possible toxicity in normal clinical use.

Antidepressants and the Risk of Cardiovascular Events in Elderly Affected by Cardiovascular Disease: A Real-Life Investigation From Italy

PURPOSE

The purpose of this study was to assess the possible relation between use of antidepressant (AD) drugs, that is, tricyclic ADs, selective serotonin reuptake inhibitors (SSRIs), and atypical ADs (AAs), and the risk of hospitalization for cardiovascular (CV) events among older patients with previous CV diseases.

METHODS

A nested case-control study was carried out among patients aged 65 years and older from 5 Italian health care territorial units who were discharged for CV disease during 2008 to 2010. The cohort was composed by 344,747 individuals, and of these, 97,739 (28%) experienced hospital admission for CV events (myocardial infarction, arrhythmia, stroke, heart failure) during follow-up (until 2014) and were included as cases. Up to 5 controls were randomly selected and matched to each. A conditional logistic regression was fitted to estimate the risk of CV events associated with ADs past or current use. A within-patient comparison was performed by the case-crossover design to account the effect of depression.

FINDINGS

Current users of SSRIs and AAs were at increased risk of CV events with odds ratios of 1.25 (95% confidence interval, 1.21-1.29) and 1.31 (1.25-1.37), respectively. An increased risk of arrhythmia and stroke was associated with current use of SSRIs and AAs, whereas an increased risk of heart failure was detected with current use of any ADs. The results were confirmed by the case-crossover approach.

IMPLICATIONS

Evidence that AD use is associated with an increased risk of CV events in accordance with specific mechanisms of action among older people with CV disease was added by this study.

Selective Serotonin Reuptake Inhibitor Use and Risk of Arrhythmia: A Nationwide, Population-Based Cohort Study

PURPOSE

This study compares the risks of arrhythmia among patients with depression receiving selective serotonin reuptake inhibitors (SSRIs) and those receiving other classes of antidepressants and among patients with depression receiving citalopram-escitalopram and those receiving other SSRIs.

METHODS

This retrospective cohort study used data from the 2000-2011 National Health Insurance Research Database in Taiwan. Patients with depression who were new antidepressant users were included in the study sample. Propensity score matching was used to balance the covariates between the comparison groups. Crude incidence rates were generated by Poisson regressions, and Cox proportional hazards regression models were used to assess the rates of arrhythmia among SSRI users and nonusers of SSRI antidepressants as well as between citalopram-escitalopram users and users of other SSRIs.

FINDINGS

Neither SSRI (hazard ratio [HR] = 0.95; 95% CI, 0.83-1.08) nor citalopram-escitalopram (HR = 1.20; 95% CI, 0.95-1.51) exposure was associated with a risk of arrhythmia compared with other, newer non-SSRI antidepressants or noncitalopram SSRIs. An increase in mortality was, however, observed among citalopram-escitalopram users (HR = 1.21; 95% CI, 1.08-1.31).

IMPLICATIONS

Citalopram, escitalopram, and other SSRIs were not associated with an elevated risk of arrhythmia compared with each other or with non-SSRI antidepressants. Nevertheless, citalopram and escitalopram were associated with an increase in mortality risk compared with other SSRIs and deserve further investigation.