Mental health interventions and future major depression among primary care patients with subthreshold depression.
BACKGROUND
Subthreshold depression is prevalent in primary care and is associated with poorer quality of life, higher health care use and increased risk of major depressive disorder (MDD). Currently, it is unclear how subthreshold depression should be managed in primary care and no studies have investigated the relationship between current models of care and the development of MDD. This study aimed to describe usual care over a six month follow-up for primary care patients with subthreshold depression and to investigate the relationship between usual care and the development of MDD.


METHODS
Data were derived from 250 participants with subthreshold depression from the diamond study, a longitudinal cohort study of primary care patients. Participants completed questionnaires at three and six months on their health care use, the interventions they received and their depression status. Interventions were categorised according to the NICE guidelines for the management of depression in adults. Generalised estimating equation (GEE) models and logistic regression were used to estimate the association between receiving an intervention and MDD over six months.


RESULTS
Four fifths (80.8%) of participants received a mental health intervention. Therapeutic listening, reassurance, pharmacotherapy and advice to exercise were most common. Subsequent MDD was predicted by history of depression, baseline depressive symptom severity and receiving a mental health intervention.


CONCLUSIONS
Usual care was assessed via patient self-report.


CONCLUSIONS
Primary care physicians deliver mental health interventions to most subthreshold patients. However, it appears that current interventions are not averting MDD. Further research to identify effective interventions which are feasible in primary care is needed.
Department of General Practice, University of Melbourne, Australia. Electronic address: sdav@unimelb.edu.au.
Sandra K
SK
Davidson
School of Public Health, The University of Queensland, Australia.
Meredith G
MG
Harris
University of Liverpool, UK.
Christopher F
CF
Dowrick
Centre for Family Medicine, Karolinska Institute, Sweden; Centre for Family Medicine, Karolinska Institute, Sweden.
Caroline A
CA
Wachtler
Melbourne School of Population and Global Health, University of Melbourne, Australia.
Jane
J
Pirkis
Department of General Practice, University of Melbourne, Australia.
Jane M
JM
Gunn
D001315:Australia / Q000453:epidemiology; D015331:Cohort Studies; D003863:Depression / Q000453:epidemiology* / Q000523:psychology / Q000628:therapy*; D003865:Major Depressive Disorder / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011320:Primary Health Care; D012307:Risk Factors; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires
Major depressive disorder; Primary care; Subthreshold depression; Treatment; Usual care