At least 1 year of antidepressant therapy for patients with anxiety appears to lower relapse risk

Discontinuation of antidepressants within a year increased the odds of relapse, and time to relapse was shorter when antidepressants were discontinued rather than continued.

Patients who have anxiety disorders that respond to antidepressants may be at increased risk of relapse in the year after discontinuing antidepressant therapy, according to a recent systematic review and meta-analysis.

Researchers assessed 28 relapse-prevention trials of 5,233 participants with anxiety who responded to antidepressants. The studies, which had a maximum follow-up of one year, compared relapse rates or time to relapse after randomizing patients to either continue antidepressants or switch to placebo. Results were published online on Sept. 13 by The BMJ.

Compared to continuation of antidepressants, discontinuation of antidepressants increased the odds of relapse (summary odds ratio, 3.11; 95% CI, 2.48 to 3.89). In addition, time to relapse was shorter when antidepressants were discontinued rather than continued (summary hazard ratio, 3.63; 95% CI, 2.58 to 5.10).

Overall, summary relapse prevalence in the placebo group was 36.4% (95% CI, 30.8% to 42.1%) compared to 16.4% (95% CI, 12.6% to 20.1%) in the antidepressant group, although prevalence varied across studies.

The researchers also examined whether relapse risk is related to type of anxiety disorder, type of antidepressant, mode of discontinuation, duration of treatment and follow-up, comorbidities, or allowance of psychotherapy. Subgroup and meta-regression analyses yielded no significant results.

The authors noted limitations to the study, such as the involvement of drug companies in all but two small studies and the considerable variation in follow-up durations between studies (range, eight to 52 weeks). Another limitation is that no randomized studies had a duration of treatment longer than one year, they added.

“Doctors should inform patients about the risk of relapse and decide collaboratively with the patient whether the benefits of discontinuation are worth the risk of relapse in their specific case. … On the basis of the evidence presented here, the advice is to continue antidepressants for at least a year. After this period, no evidence based advice can be provided,” the authors wrote.