A collaborative care model significantly mitigated mild depression in adults aged 65 and older, compared with usual care in the short term, based on data from 705 patients. The findings were published online Feb. 21.
“There is limited research about older people with mild depressive disorders who have insufficient levels of depressive symptoms to meet diagnostic criteria (called subclinical, subthreshold, or subsyndromal depression) but also reduced quality of life and function,” wrote Simon Gilbody, PhD, of the University of York (England) and colleagues. However, subthreshold depression increases the risk of a severe depressive illness, the researchers added.
In the Collaborative Care for Screen Positive Elders (CASPER) trial, the researchers randomized 344 patients to collaborative care, and 361 control patients received standard primary care. The collaborative care intervention involved assessment of functional impairment and mood, followed by eight weekly sessions of behavioral activation that consisted of telephone support and symptom monitoring at each session after an initial face-to-face session. Symptoms were assessed using the 9-item Patient Health Questionnaire depression score ( PHQ-9 ), with a scale of 0-27.
Overall, patients in the collaborative care group improved from an average score of 7.8 at baseline to 5.4 after 4 months; the usual care group improved from an average of 7.8 at baseline to 6.7 at 4 months. The difference in scores persisted at 12 months in the secondary analysis (JAMA. 2017;317:728-37. doi: 10.1001/jama.2017.0130 ). “For populations with case-level depression, a successful treatment outcome has been defined as 5 points on the PHQ-9,” the researchers noted. “This magnitude of benefit was not observed in either group of the trial when comparing scores before and after treatment, although this result would be anticipated given the lower baseline PHQ-9 scores in populations with subthreshold depression.’
The study participants came from 32 primary care practices in northern England; the average age was 77 years, and 58% were women.
The results were limited by several factors, including the absence of a standardized interview to diagnose depression, differences in retention and attrition between groups, and the absence of long-term follow-up, “and further research is needed to assess longer-term efficacy,” the researchers said.
Neither Dr. Gilbody nor his colleagues had financial conflicts to disclose.