title: Depression is a risk factor for noncompliance with medical treatment: meta-analysis of the effects of anxiety and depression on patient adherence.
abstract: BACKGROUND
  Depression and anxiety are common in medical patients and are associated with diminished health status and increased health care utilization. This article presents a quantitative review and synthesis of studies correlating medical patients' treatment noncompliance with their anxiety and depression.
  
  
  METHODS
  Research on patient adherence catalogued on MEDLINE and PsychLit from January 1, 1968, through March 31, 1998, was examined, and studies were included in this review if they measured patient compliance and depression or anxiety (with n>10); involved a medical regimen recommended by a nonpsychiatrist physician to a patient not being treated for anxiety, depression, or a psychiatric illness; and measured the relationship between patient compliance and patient anxiety and/or depression (or provided data to calculate it).
  
  
  RESULTS
  Twelve articles about depression and 13 about anxiety met the inclusion criteria. The associations between anxiety and noncompliance were variable, and their averages were small and nonsignificant. The relationship between depression and noncompliance, however, was substantial and significant, with an odds ratio of 3.03 (95% confidence interval, 1.96-4.89).
  
  
  CONCLUSIONS
  Compared with nondepressed patients, the odds are 3 times greater that depressed patients will be noncompliant with medical treatment recommendations. Recommendations for future research include attention to causal inferences and exploration of mechanisms to explain the effects. Evidence of strong covariation of depression and medical noncompliance suggests the importance of recognizing depression as a risk factor for poor outcomes among patients who might not be adhering to medical advice.
authors.affiliation: Department of Psychology, University of California, Riverside, CA 92521, USA. robin@citrus.ucr.edu
authors.forename: M R
authors.initials: MR
authors.lastname: DiMatteo
authors.forename: H S
authors.initials: HS
authors.lastname: Lepper
authors.forename: T W
authors.initials: TW
authors.lastname: Croghan
mesh_terms: D000328:Adult; D001007:Anxiety / Q000150:complications / Q000453:epidemiology; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000628:therapy; D003863:Depression / Q000150:complications / Q000453:epidemiology*; D006304:Health Status; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000628:therapy; D009369:Neoplasms / Q000150:complications / Q000628:therapy; D016017:Odds Ratio; D017063:Outcome Assessment, Health Care; D010349:Patient Compliance; D012189:Retrospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D016312:Treatment Refusal