Duloxetine Treatment in Elderly With Dysthymia

Study Summary

Dysthymic disorder (DD) denotes chronic depression with fewer symptoms than major depressive disorder (MDD), and it affects \~ 2-4 % of adults with a similar prevalence in the elderly. In the elderly, dysthymic disorder (DD) has been shown to be associated with suffering and disability. The differences between young adult and elderly DD patients indicate that findings obtained in young adults with DD cannot be extrapolated to elderly DD patients who need to be studied separately. Data from epidemiologic studies support this view. In contrast to the data in young adult DD patients, there is a paucity of controlled data on the treatment of elderly DD patients. In our center, a double-masked, placebo-controlled study of 91 elderly DD patients did not find significant superiority for fluoxetine over placebo with response rates of 27.3% for fluoxetine and 19.6% for placebo in intent-to-treat analyses, and response rates of 37.5% for fluoxetine and 23.1% for placebo in completer analyses. Given the relative failure of selective serotonin reuptake inhibitor (SSRIs) to treat geriatric DD effectively, the investigators decided to evaluate the dual reuptake inhibitor, venlafaxine. The investigators earlier completed an investigator-initiated, open-label 12-week venlafaxine (Effexor XR) trial. Of 23 elderly DD patients, 18 completed the trial. Fourteen (60.9%) were responders in intent-to-treat analyses with the last observation carried forward, and 77.8% were responders in completer analyses. Nearly half the sample (47.8%) met criteria for remission. In the intent-to-treat sample, increased severity of depression at baseline was associated with superior response and the presence of cardiovascular disease was associated with poorer response. These results with venlafaxine indicate that further treatment studies of dual serotonin-norepinephrine reuptake inhibitors like duloxetine are warranted in elderly patients with dysthymic disorder.

Primary Outcome

The research rater completed the 24-item Hamilton Rating Scale for Depression (HAM-D) and documented the scores on each visit. Hamilton Rating Scale for Depression scores range from 0-50 with low scores or decreasing scores representing decreased severity and better outcome, and higher scores or increasing scores representing more severe depressive symptoms and a worse outcome. The change score was calculated by subtracting the Week 12 score from the Week 0 score.

Interventions

• DRUG Duloxetine