title: Coincident alcohol dependence and depression increases risk of suicidal ideation among Army National Guard soldiers.
abstract: Suicide rates among military service members have risen dramatically, while drivers remain poorly understood. We examined the relationship between coincident alcohol dependence and depression in shaping risk of suicidal ideation among National Guard forces.
  
  
  
  We performed a longitudinal analysis using a randomly selected, population-based sample of Ohio Army National Guard soldiers. Telephone-based surveys of 1582 soldiers who participated in both wave 1 (2008-2009) and wave 2 (2009-2010) were analyzed.
  
  
  
  Odds ratios (ORs) for suicidal ideation among those with versus without alcohol dependence were similar among nondepressed (OR = 3.85 [95% confidence intervals (CIs) = 1.18-12.52]) and depressed individuals (OR = 3.13 [95% CI = 0.88-11.14]); multiplicative interaction was not observed. In contrast, the risk differences (RDs) among those with versus without alcohol dependence diverged for those without depression (RD = 0.04 [95% CI = 0.02-0.07]) compared with those with depression (RD = 0.11 [95% CI = 0.06-0.18]); strong evidence of additive interaction was observed.
  
  
  
  We found that alcohol dependence and depression interact statistically in shaping risk for incident suicidal ideation among Army National Guard service members. A high-risk prevention approach including population-based screening for suicidality among patients with alcohol dependence, depression, and particularly those with both conditions is warranted in military populations.
authors.affiliation: Department of Epidemiology, Boston University School of Public Health, Boston, MA; Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY. Electronic address: ghcohen@bu.edu.
authors.forename: Gregory H
authors.initials: GH
authors.lastname: Cohen
authors.affiliation: Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY.
authors.forename: David S
authors.initials: DS
authors.lastname: Fink
authors.affiliation: Department of Epidemiology, Boston University School of Public Health, Boston, MA.
authors.forename: Laura
authors.initials: L
authors.lastname: Sampson
authors.affiliation: Department of Psychiatry, University of Toledo Health Science Center, Toledo, OH.
authors.forename: Marijo
authors.initials: M
authors.lastname: Tamburrino
authors.affiliation: Department of Psychiatry, University of Michigan, Ann Arbor.
authors.forename: Israel
authors.initials: I
authors.lastname: Liberzon
authors.affiliation: Department of Psychiatry, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH.
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Calabrese
authors.affiliation: Department of Epidemiology, Boston University School of Public Health, Boston, MA; Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY.
authors.forename: Sandro
authors.initials: S
authors.lastname: Galea
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000453:epidemiology / Q000523:psychology*; D003866:Depressive Disorder / Q000453:epidemiology / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008889:Military Personnel / Q000523:psychology*; D009820:Ohio / Q000453:epidemiology; D012307:Risk Factors; D013313:Stress Disorders, Post-Traumatic / Q000453:epidemiology / Q000523:psychology*; D059020:Suicidal Ideation; D013405:Suicide / Q000523:psychology* / Q000706:statistics & numerical data*
keywords: Alcohol dependence; Depression; Interaction; Military service members; National Guard; Suicidal ideation