Depression causes significant suffering and is commonly seen in primary care. Because primary care providers sometimes fail to identify patients as depressed, systematic screening programs in primary care may be of use in improving outcomes in depressed patients. Depression screening is predicated on the notion that identification will allow effective treatments to be delivered and that the benefits of treatment will outweigh the harms. Treatment efficacy of antidepressants and psychotherapy in general adult populations was established in a previous United States Preventive Services Task Force (USPSFT) review on depression screening, but treatment in older adults was not examined specifically. Additionally, harms of screening and treatment were not previously examined in detail.
This evidence report updates the evidence for the benefits and harms of screening primary care patients for depression in order to initiate or modify treatment aimed at providing relief from depression.
We developed an analytic framework and five key questions to represent the logical evidence connecting primary care screening to improved health outcomes, including remission from depression. We searched Medline, Cochrane Central Registry of Controlled Trials, and PsycINFO from 1998 to December 2007, and Cochrane Database of Systematic Reviews from 1998–October 2006 (with updates through December 2007). Separate literature search strategies were developed for harms of screening and harms of treatment. We also considered all trials included in the previous systematic review for the USPSTF and a recent Cochrane review on depression screening in primary care, contacted experts, and checked bibliographies from non-systematic reviews and other studies. We examined 4088 abstracts and 412 full-text articles.
For all key questions, we considered evidence from studies published in English that were conducted in the United States or other similarly developed countries and met design-specific USPSTF quality standards. We included fair-to-good quality randomized clinical trials (RCTs) or controlled clinical trials (CCTs) that evaluated screening for depression in primary care settings if the screening and related interventions involved general adult primary care populations and if the control group was either unscreened or the results of the screening were not used in the care of the patient. We found no trials or studies addressing harms of screening. We included good-quality meta-analyses that examined depression treatment efficacy in older adults. We included fair-to-good quality systematic reviews, meta-analyses, and large observational studies of serious adverse events and early discontinuation due to adverse effects in adult and older adults.
One reviewer abstracted relevant information from each included article into standardized evidence tables, and a second reviewer checked all elements. Two reviewers graded the quality of each article using USPSTF criteria. Excluded articles are listed in tables, along with the primary reason(s) for exclusion.
Programs that include depression screening and staff that assist the primary care clinician by providing some direct depression care (such as care support or coordination, case management, or mental health treatment) can increase depression response and remission over usual care. However, it is unclear whether screening is a necessary component of these programs. Depression screening programs that do not provide depression care supports other than those targeted at improving the effectiveness of the primary care provider’s depression treatment (without additional staff involvement) are unlikely to be effective. Antidepressants and psychotherapy are effective in treating depression in older adults, with odds of remission about twice those seen in placebo or other non-active control conditions. The most current evidence on risk of completed suicide deaths does not demonstrate a clear and uniform effect of second-generation antidepressants compared with placebo; rather, data are consistent with no effect, mild protection or some increased risk. Some meta-analyses suggest an increase in suicidal behaviors in young adults (aged 18–29 years) on antidepressants, particularly those with major depressive disorder and those taking paroxetine. In contrast, older adults have a reduced risk of suicidal behaviors during antidepressant treatment.
Screening programs without staff-assisted depression care supports are unlikely to improve depression outcomes, although depression treatment can be effective in adults of all ages. Close monitoring of all adult patients initiating antidepressant treatment, particularly those under age 30, is important both for safety reasons and to ensure optimal treatment response.
