title: Mental health literacy, folic acid and vitamin B12, and physical activity for the prevention of depression in older adults: randomised controlled trial.
abstract: BACKGROUND
  Few randomised controlled trials (RCTs) have examined potential preventive agents in high-risk community populations.
  
  
  OBJECTIVE
  To determine whether a mental health literacy intervention, the promotion of physical activity, or folic acid plus vitamin B(12) reduce depression symptoms in community-dwelling older adults with elevated psychological distress.
  
  
  METHODS
  An RCT with a completely crossed 2 x 2 x 2 factorial design: (400 mcg/d folic acid + 100 mcg/d vitamin B(12) v. placebo)x(physical activity v. nutrition promotion control)x(mental health literacy v. pain information control). The initial target sample size was 2000; however, only 909 adults (60-74 years) met the study criteria. Interventions were delivered by mail with telephone calls. The main outcome was depressive symptoms on the Patient Health Questionnaire (PHQ-9) at 6 weeks, 6, 12 and 24 months. The Clinicaltrials.gov registration number is NCT00214682.
  
  
  RESULTS
  The drop-out rate was low (13.5%) from randomisation to 24-month assessment. Neither folic acid + B(12) (F(3,856) = 0.83, P = 0.476) nor physical activity (F(3,856) = 1.65, P = 0.177) reduced depressive symptoms at any time point. At 6 weeks, depressive symptoms were lower for the mental health literacy intervention compared with its control condition (t(895) = 2.04, P = 0.042).
  
  
  CONCLUSIONS
  Mental health literacy had a transient effect on depressive symptoms. Other than this, none of the interventions significantly reduced symptoms relative to their comparator at 6 weeks or subsequently. Neither folic acid plus B(12) nor physical activity were effective in reducing depressive symptoms.
authors.affiliation: Centre for Mental Health Research, Australian National University, Building 63 Eggleston Road, Acton, Australian Capital Territory, 0200 Australia. Janine.Walker@anu.edu.au
authors.forename: Janine G
authors.initials: JG
authors.lastname: Walker
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Mackinnon
authors.forename: Philip
authors.initials: P
authors.lastname: Batterham
authors.forename: Anthony F
authors.initials: AF
authors.lastname: Jorm
authors.forename: Ian
authors.initials: I
authors.lastname: Hickie
authors.forename: Affrica
authors.initials: A
authors.lastname: McCarthy
authors.forename: Michael
authors.initials: M
authors.lastname: Fenech
authors.forename: Helen
authors.initials: H
authors.lastname: Christensen
mesh_terms: D000368:Aged; D003863:Depression / Q000517:prevention & control*; D019587:Dietary Supplements; D004338:Drug Combinations; D005260:Female; D005492:Folic Acid / Q000009:adverse effects / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006266:Health Education / Q000379:methods*; D006801:Humans; D008297:Male; D008603:Mental Health; D008875:Middle Aged; D009043:Motor Activity; D010352:Patient Dropouts / Q000706:statistics & numerical data; D011569:Psychiatric Status Rating Scales; D014805:Vitamin B 12 / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D004338:Drug Combinations; D005492:Folic Acid; D014805:Vitamin B 12