Doctors should not routinely screen their patients for depression because doing so is impractical and not particularly useful. However, they should be on the lookout for tell-tale signs of depression such as suicidal thoughts, insomnia and anhedonia (the inability to experience pleasure).
That, in short, is the new recommendation from the Canadian Task Force on Preventive Health Care, an independent body that develops clinical practice guidelines. They were published Monday in the Canadian Medical Association Journal.
“Depression is an important health issue but there is no convincing evidence that screening makes a difference – it doesn’t lead to better outcomes,” Dr. Michel Joffres, a professor in the faculty of health science at Simon Fraser University in Burnaby, B.C. and chair of the CTFPHC depression guideline writing group, said in an interview.
“We’re not telling physicians to do nothing,” he said. “We’re actually pushing them to be more alert instead of relying on screening tools.”
The Canadian approach differs from that in other countries. The U.S. Preventive Services Task Force recommends universal screening for depression, but only where programs exist to ensure follow-up treatment.
That is an identical approach to the earlier Canadian guidelines, issued in 2005. Dr. Joffres said those recommendations focused on how to do proper follow-up to screening rather than questioning whether screening was useful in the first place.
The National Institute for Health and Care Excellence in Britain, for its part recommends focusing on people with a personal or family history of depression rather than general screening.
Dr. Gabriela Lewin, a family physician in Kemptville, Ont., and member of the CTFPHC working group said the evidence does not support universal screening or even targeting people from groups at higher risk of depression like those with substance abuse problems, those who have suffered trauma, or living with a chronic illness.
She stressed, however, that "these recommendations do not apply to people with known depression, with a history of depression or who are receiving treatment for depression.
“Patients who present with symptoms or other clues to the presence of depression should be appropriately assessed," Dr. Lewin said.
Depression is a mood disorder that affects the way a person feels thinks or behaves. It can be triggered by biological, psychosocial or environmental factors, such as trauma.
About one in eight adults will suffer depression during their lifetime.
It is not clear if the new guidelines will make any difference to front-line care and treatment. That is because there are no data showing how many physicians actually do routine screening now.
The screening test for depression consists of a questionnaire that identifies nine key symptoms of depression; if a patient suffers from five or more of those symptoms within a two-week period, they are considered to be clinically depressed, and follow-treatment is recommended.
Treatment for depression includes prescription of antidepressant medication, psychological counseling or a combination of the two.