Twelve month outcome of depression in general practice: does detection or disclosure make a difference?

OBJECTIVES: To assess the extent to which the outcome of depression among primary care attenders may be affected by medical diagnosis or by feedback of questionnaire results in unrecognised cases. DESIGN: Prospective 12 month study including a randomised controlled trial of the effects of disclosure, with data on depression status and clinical management collected by questionnaire and interview. SETTING: Two group practices in north Liverpool. SUBJECTS: 1099/1444 (76%) consecutive adult attenders completed the Beck depression inventory, of whom 179 with scores of at least 14 were followed up. INTERVENTIONS: Disclosure of a random 45% (52/116) of depression scores to general practitioners for subjects whose depression was undetected. MAIN OUTCOME MEASURES: Depression status estimated by depression score at start of study and at six and 12 months, with subsample validation against ICD-10 criteria. RESULTS: Questionnaire response rates were 76% (136/179) at six months and 68% (122/179) at 12 months and were higher for women than men. The median depression score was 19 (interquartile range 15 to 22) initially, decreasing to 16 (11 to 23) at 12 months. The median depression score decreased significantly (two sided test, P = 0.019) in subjects whose depression was unrecognised at the index consultation but increased in those whose depression had been detected by their general practitioners. Disclosure of cases of unrecognised depression to general practitioners had no effect on outcome. Intention to treat was associated with a worse prognosis, although only a minority of subjects received adequate treatment. CONCLUSIONS: Disclosure of undetected depression did not improve prognosis. A diagnosis of depression in general practice should be considered simply as a marker of its severity.