Clinical outcomes vary among older adults taking antidepressants

Use of commonly used antidepressants may result in different outcomes among older adults initiating this medication for depression, as shown in a study.

This result “may inform benefit-risk evaluation at treatment initiation and highlights the importance of careful selection of antidepressant treatment,” according to the investigators.

Nationwide Danish registry data were used in this cohort study and included 93,883 older adults (mean age 78.0 years, 56 percent female) who redeemed a first-time (since 1995) antidepressant prescription with an indication of depression between 2006 and 2017. The analysis included only the 10 most frequently used antidepressant medications.

Outcomes assessed were as follows: discontinuation, switching, augmentation, psychiatric hospital contacts, suicide attempt or self-harm, fall-related injuries, cardiovascular events, and all-cause mortality. Poisson regression models, controlled for potential confounders, were used to estimate the incidence rate ratios (IRRs) and 95 percent confidence intervals (CIs).

Antidepressants commonly prescribed included selective serotonin reuptake inhibitors (citalopram, 47.04 percent; escitalopram, 11.81 percent; fluoxetine, 0.55 percent; paroxetine, 0.52 percent; sertraline, 11.17 percent), serotonin-norepinephrine reuptake inhibitors (duloxetine, 0.71 percent; venlafaxine, 1.54 percent), a tricyclic antidepressant (amitriptyline, 1.86 percent), and two atypical antidepressants (mianserin, 1.93 percent; mirtazapine, 22.87 percent).

Compared with users of sertraline (reference drug), users of the other nine antidepressants were at significantly greater risk of discontinuation (eg, mirtazapine: IRR, 1.55, 95 percent CI, 1.50–1.61; venlafaxine: IRR, 1.22, 95 percent CI, 1.12–1.32), switching (amitriptyline: IRR, 1.45, 95 percent CI, 1.15–1.81; venlafaxine: IRR, 1.47, 95 percent CI, 1.20–1.80), augmentation, cardiovascular events, and mortality.

In addition, adverse outcomes occurred more frequently among users of mirtazapine and venlafaxine than sertraline users. Analyses stratified by sex and age (≤75 years vs. >75 years) revealed similar results.