Age of Onset Doesn't Affect Treatment Response in Elderly

Elderly patients who have their first episode of major depression late in life may differ from those with early-onset depression in disease pathology, but their responses to antidepressant treatment appear similar, a group of University of Texas researchers concluded after parsing data from the large Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study.

Among the participants in the STAR*D study, the authors focused on 574 who were 55 to 75 years old with a diagnosis of major depression. They compared the patients (72 percent) who had their first depressive episode at or before age 55 (early-onset depression) and the patients who had their first episode after age 55 (late-onset depression) (28 percent), and found that both groups had similar outcomes after getting up to 14 weeks of treatment with citalopram. The dosage of citalopram was adjusted according to the study protocol for all participants.

The percentage of patients who achieved remission was similar in both types of patients (see chart), as were several other clinical measurements, such as rates of response, percent change from baseline in standardized depression assessment score, and time to remission. There were, however, some subtle differences between elderly patients with early- and late-onset depression. Patients in the early-onset group reported that their first depressive episode occurred on average at 31 years old, and thus they had lived with the illness for decades; the late-onset group reported that their first episode occurred around age 62. The early-onset group also had a higher proportion of comorbid social phobia and posttraumatic stress disorder than the late-onset group.

The authors also noted that the average citalopram dose at the end of the study was statistically significantly higher in the early-onset patients than the late-onset patients, with the actual mean doses at 39.2 mg versus 35.7 mg, respectively.

Previous research has suggested that depression emerging later in life may be related to vascular changes in the brain and different from the etiology of the early-onset type, according to the authors. Such changes, however, do not seem to affect the treatment of elderly patients with depression and their outcomes.

“The findings should inspire some enthusiasm for clinicians to treat depression aggressively and keep at it,” said Robert Roca, M.D., chair of APA's Council on Aging and vice president and medical director of Sheppard Pratt Health System. He cited past research indicating that patients with cerebral vascular diseases, especially after a stroke, are at heightened risks for depression.

“There has been a presumption that these patients with late-onset depression might be less responsive to treatment for mood disorder.” He believes physicians should maintain “an expectation of recovery or remission for their patients” despite the vascular aspects of the disorder as the study findings support the effectiveness of antidepressant treatment.

Roca also emphasized that treating elderly patients for depression requires a comprehensive approach and collaboration with the patient's primary care physician, specialists, and caregivers.

“We must employ other modalities and be mindful of comorbidities such as pain and medical conditions that can be very demoralizing for the patient,” he said. “In these elderly patients, the social network and connection with other people are particularly important to their psychiatric recovery.”

To achieve optimal outcomes, he recommended that psychiatrists attend to patients' psychosocial needs and make appropriate interventions in addition to pharmacological treatment.

The study was funded by grants from the National Institute of Mental Health and published in the January American Journal of Geriatric Psychiatry.

An abstract of “Treatment Outcomes for Older Depressed Patients With Earlier Versus Late Onset of First Depressive Episode” is posted at<www.ajgponline.org/cgi/content/abstract/16/1/58>.▪