title: Elucidating the Biological Mechanisms Linking Depressive Symptoms With Type 2 Diabetes in Men: The Longitudinal Effects of Inflammation, Microvascular Dysfunction, and Testosterone.
abstract: OBJECTIVE
  This prospective cohort study sought to examine key biological measures linking depressive symptoms with Type 2 diabetes, specifically inflammation, microvascular dysfunction, and androgens.
  
  
  METHODS
  A cohort of 688 men without diabetes who were 35 years or older were followed up for 5 years. Venous interleukin-6, high-sensitivity C-reactive protein, sE-selectin, endogenous total testosterone, fasting glucose, and glycated hemoglobin (HbA1c) were quantified at baseline and 5 years later. Depressive symptoms were assessed using the Beck Depression Inventory-I, and men were categorized into persistent, remitted, incident, and nondepressed groups (reference). Logistic regression was used to determine odds ratios (ORs) for diabetes adjusted for propensity score calculated from 18 established risk factors.
  
  
  RESULTS
  Diabetes developed in 112 men (16.3% of sample). Persistent depressive symptoms were associated with diabetes (adjusted OR = 2.45, 95% confidence interval [CI] = 1.16-5.20, p = .019). Baseline testosterone (OR = 0.43, 95% CI = 0.22-0.81, p = .01) and follow-up testosterone (OR = 0.51, 95% CI = 0.31-0.84, p = .008) were inversely associated with Type 2 diabetes. Annualized HbA1c was positively associated with annualized change in cognitive Beck Depression Inventory symptoms (β = 0.14, p = .001) and inversely associated with annualized change in testosterone (β = -0.10, p = .014). Annualized change in fasting glucose was associated with sE-selectin (β = 0.12, p < .001) and somatic depressive symptoms (β = -0.12, p = .002).
  
  
  CONCLUSIONS
  The findings suggest that lower endogenous total testosterone levels and persistent depressive symptoms were associated with Type 2 diabetes risk and HbA1c in men over a 5-year period.
authors.affiliation: From the Freemasons Foundation Centre for Men's Health (Tully, Martin, Wittert), Discipline of Medicine (Tully, Martin, Wittert), and Population Research & Outcome Studies (Taylor), School of Medicine, The University of Adelaide, Adelaide, Australia; INSERM (Tully), U897-Epidemiology and Biostatistics, Bordeaux, France; Department of Rehabilitation Psychology and Psychotherapy, Institute of Psychology (Tully, Baumeister), and Medical Psychology and Medical Sociology, Medical Faculty (Baumeister), University of Freiburg, Freiburg, Germany; School of Nursing and Midwifery (Atlantis), University of Western Sydney, Sydney, New South Wales, Australia; University of Sydney (Jenkins, Januszewski), NHMRC Clinical Trials Centre, Sydney, New South Wales, Australia; and Institute of Medical and Veterinary Science Pathology (O'Loughlin), Adelaide, South Australia, Australia.
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Tully
authors.forename: Harald
authors.initials: H
authors.lastname: Baumeister
authors.forename: Sean
authors.initials: S
authors.lastname: Martin
authors.forename: Evan
authors.initials: E
authors.lastname: Atlantis
authors.forename: Alicia
authors.initials: A
authors.lastname: Jenkins
authors.forename: Andrzej
authors.initials: A
authors.lastname: Januszewski
authors.forename: Peter
authors.initials: P
authors.lastname: OʼLoughlin
authors.forename: Anne
authors.initials: A
authors.lastname: Taylor
authors.forename: Gary A
authors.initials: GA
authors.lastname: Wittert
mesh_terms: D000328:Adult; D001315:Australia / Q000453:epidemiology; D001786:Blood Glucose; D002097:C-Reactive Protein; D015331:Cohort Studies; D015897:Comorbidity; D003866:Depressive Disorder / Q000097:blood* / Q000453:epidemiology / Q000523:psychology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000453:epidemiology / Q000523:psychology; D019040:E-Selectin / Q000097:blood; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin; D006801:Humans; D007249:Inflammation / Q000097:blood* / Q000453:epidemiology*; D015850:Interleukin-6 / Q000097:blood; D008137:Longitudinal Studies; D008297:Male; D055806:Microvessels / Q000503:physiopathology*; D011446:Prospective Studies; D012307:Risk Factors; D013739:Testosterone / Q000097:blood*
chemical_list: D001786:Blood Glucose; D002097:C-Reactive Protein; D019040:E-Selectin; D006442:Glycated Hemoglobin; D015850:Interleukin-6; D013739:Testosterone