An open treatment trial of duloxetine in elderly patients with dysthymic disorder

We evaluated the efficacy and side effects of the selective serotonin and norepinephrine reuptake inhibitor antidepressant duloxetine in older adults with dysthymic disorder.

Patients ≥ 60 years old with dysthymic disorder received flexible dose duloxetine 20-120 mg daily in an open-label 12-week trial. The main outcomes were change from baseline to 12 weeks in 24-item Hamilton Depression Rating Scale scores and Treatment Emergent Symptoms Scale scores. Response required ≥ 50% decline in Hamilton Depression Rating Scale scores with a Clinical Global Impression of much improved or better, and remission required final Hamilton Depression Rating Scale ≤ 6. Intent-to-treat analyses were conducted with the last observation carried forward.

In 30 patients, the mean age was 70.7 (standard deviation (SD) = 7.6) years and 56.7% were female. In intent-to-treat analyses, there were 16 responders (53.3%) and 10 remitters (33.3%). Of these, 19 patients completed the trial. The mean maximum dose was 76.3 mg (SD = 38.5) in the total sample and 101 mg (SD = 17.9) in completers. In the total sample, the mean final dose was 51 mg (SD = 27.2) and correlated significantly with decline in Hamilton Depression Rating Scale (p < .03); decline in Hamilton Depression Rating Scale correlated significantly with decline in Treatment Emergent Symptoms Scale (p < .001). Daily doses above 60 mg were associated with greater improvement and well tolerated. This result was partly confounded by early dropouts having received low doses. Demographic and medical comorbidities, including cardiac disease and hypertension, were not related to response. Somatic side effects were common prior to duloxetine treatment and improved rather than worsened with duloxetine. There were no serious adverse events.

Duloxetine at relatively high doses showed moderate efficacy in elderly patients with dysthymic disorder and was well tolerated in successful completers. Reduced somatic symptoms were associated with improvement in depressive symptoms. A systematic placebo-controlled trial of duloxetine in older patients with dysthymic disorder may be warranted.