Are antidepressants all the same? Surveying the opinions of Australian psychiatrists.

OBJECTIVE

Controlled trials do not suggest differences in efficacy between antidepressant compounds. Psychiatrists, however, frequently express the view that real differences do exist and are relevant to clinical practice. Since multiple comparative trials are not feasible, an alternative method for expanding the evidence base is to survey regularly the opinions of practising psychiatrists.

METHODS

Two surveys of psychiatrists' opinions were conducted. Participants in the first survey were drawn from contact with 'SPHERE: A National Depression Project', while those in the second survey responded to a brief questionnaire distributed with Australasian Psychiatry.

RESULTS

Reported volumes of scripts written, ratings of efficacy and tolerability, and preferences in specific clinical situations indicate that clinical psychiatrists now strongly prefer the newer antidepressant agents. They rate serotonin and noradrenalin re-uptake inhibitors (SNRIs) and selective serotonin re-uptake inhibitors (SSRIs) highest for antidepressant efficacy, serotonin receptor subtype 2 (5HT2) antagonists and some SSRIs highest for anti-anxiety efficacy, and some SSRIs and reversible inhibitors of monoamine oxidase inhibitor-A (RIMAs) lowest for side-effect burden. Further, SSRIs were their first preferences for most clinical situations. Serotonin and noradrenalin re-uptake inhibitors were the preferred choice for treatment-resistant depression and patients who had failed to respond to one SSRI. Serotonin receptor subtype 2 antagonists were the second choice to SSRIs for mixed anxiety and depression, and major depression with sleep disturbance. Reversible inhibitors of monoamine oxidase inhibitor-A were the second choice to SSRIs for adolescents with major depression, patients aged over 65 years, patients with serious medical illnesses and patients with chronic fatigue. Tricyclic antidepressants (TCAs) were the preferred choice for patients with chronic pain, and second choice to SSRIs for patients with major depression with panic disorder, postnatal disorders and patients with psychotic depression.

CONCLUSIONS

Psychiatrists believe that important differences do exist between available antidepressant compounds. Such opinions are divergent from limited controlled data but may be influenced by a wide range of factors other than direct clinical experience. The role of such surveys in ongoing evaluation of clinical practice is emphasised.