Subjective recognition of adverse events with antidepressant in people with depression: a prospective study

Background: While it has been reported that physicians may under-recognize adverse effects of antidepressants thoroughly in clinical settings, subjective bias in recognition of adverse effects (AEs) with antidepressants has not been specifically investigated.

Methods: Four-hundred ninety-three participants with depressive disorders (ICD-10) were assessed for the severity of 20 common AEs and their inferred causal relationship with antidepressants, together with the Quick Inventory for Depressive Symptoms (QIDS). These assessments occurred twice at the 1st visit (when they were antidepressant free) and 2nd visit (10 days after the initiation of antidepressants). 'Possible AEs' and 'under-recognized AEs' were defined as 'events with exacerbation in the severity' and 'events with negative causal attribution to antidepressants' at the time of the 2nd visit, respectively.

Results: Three-hundred sixty-three participants (73.6%) experienced ≥ 1 under-recognized AEs. Flu like symptoms (96.5% of participants who experienced possible AEs), sexual dysfunction (94.2%), blurred vision (93.4%), anxiety/tension (91.1%) and sweating (89.2%) were found to be prevalent as under-recognized AEs. Participants with under-recognized AEs had less improvement in the QIDS than those without (27.1% vs. 11.1% decrease, p<0.001).

Limitations: It is intrinsically challenging to exactly differentiate between antidepressant AEs and symptoms of depression. And the severity of depression, that of AEs and causal relationship between AEs and antidepressants were assessed not by objective but subjective scales.

Conclusions: An overall trend to under-recognize AEs of antidepressants was found and people with a lesser degree of early improvement tend to understate the causality, which has an implication in interpreting voluntarily expression of AEs.