Pharmacological concerns need epidemiological elucidation

Patients with depressive disorders could be more liable to accidents than others for several reasons. These include impaired attention and concentration (often due to preoccupation with morbid or worrying thoughts); anxiety, which usually accompanies depression; irritability; agitation or retardation; fatigue after sleepless nights; and weakness due to insufficient food intake. In addition, depressed patients may take risks with little regard to the consequences, make suicidal gestures or attempts that go wrong, and take alcohol or other substances that impair functioning to relieve distress. In keeping with these considerations are the reductions in performance in tests of cognitive and psychomotor function in depressed patients.1

If depression causes or contributes to accidents in these ways then therisk of accidents might be expected to fall as the disorder improves in response to treatment with antidepressant drugs (or other treatment). On the other hand, the unwanted effects of antidepressants may adversely affect cognitive and psychomotor function (especially in those with pre-existing cerebral impairment), thereby increasing the risk of accidents. This is particularly the case in patients who do not respond to treatment and thus are impaired by both the depression and the drug. Drug induced effects may be clinically obvious, with, for example, somnolence due to oversedation; mild effects may be evident only on formal psychometric testing. In tests of higher central nervous system functions the older tricyclic antidepressants, such …