Guidelines for depression improve patient outcomes
A primary care study from the US has assessed the extent to which clinicians follow depression guidelines and whether there is a correlation with patient outcomes.
Data were collected from 1,131 patients with depression participating in quality improvement studies, of whom 58% received enhanced care (eg using practice nurses to provide managed care1) and 42% received care as usual.
At six and 12 months' follow-up, a patient questionnaire was used to assess clinicians' adherence to 20 guideline recommendations. Patient outcomes were measured at 12, 18 and 24 months' follow-up, using a measure (modified CES-D) based on the DSM-IV criteria.
Primary care physicians were good at following the guidelines for the detection of depression during follow-up (79% adherence) and initiating appropriate treatment (84% adherence).
However, they were less successful at following up patients: only 46% of patients completed the minimum duration of antidepressant treatment (two months) or psychotherapy (four visits).
Guideline adherence was low (23% to 38%) for eight indicators, which covered suicide risk management, assessment of alcohol misuse, assessment of depression severity, adjustment of treatment in nonresponsive patients and treatment of the elderly.
Adherence scores were averaged across the 20 indicators to create an overall quality of care index. After controlling for patient prognosis, a significant inverse relationship was found between quality of care and the probability of persistent depression at 18 and 24 months. This suggests that doctors whose practice is concordant with guidelines achieve better outcomes; as an observational study, however, a causal link cannot be established.
The relationship between quality of care and outcomes was modest: the largest benefit was in patients with the worst prognosis, for whom the probability of depression at 24 months was 0.51 where high quality care was provided and 0.61 where the quality of care was low (NNT = 10).
I suspect that more objective measurement of the response to antidepressant treatment would lead to more treatment adjustment in partially responsive or nonresponsive patients.
Hepner KA, Rowe M, Rost K et al. The effect of adherence to practice guidelines on depression outcomes. Ann Intern Med 2007;147:320-329Reviewer
Dr Phillip Bland