title: Is the association between depressive symptoms and glucose metabolism bidirectional? Evidence from the English Longitudinal Study of Ageing.
abstract: OBJECTIVE
  To examine whether the prospective association between depressive symptoms and glucose metabolism is bidirectional.
  
  
  METHODS
  We used a national sample of 4238 community-dwelling individuals 50 years or older from the English Longitudinal Study of Ageing. Participants were categorized into normoglycemic, impaired glucose metabolism (IGM), and undiagnosed and diagnosed diabetes using glycated hemoglobin and self-reported doctor diagnosis. Subthreshold and elevated depressive symptoms were defined by a score between 2 and 3 and 4 or higher, respectively, on the eight-item Center for Epidemiological Studies-Depression scale.
  
  
  RESULTS
  In the age-adjusted model, categories of depressive symptoms were associated with incident undiagnosed (odds ratio [OR] = 1.54 [95% confidence interval {CI} = 0.86-2.73] and OR = 1.91 [95% CI = 1.03-3.57] for subthreshold and elevated depressive symptoms, respectively) and diagnosed diabetes (OR = 1.53 [95% CI = 0.80-2.93] and OR = 3.03 [95% CI = 1.66-5.54], respectively) for 6 years of follow-up. The latter association remained significant after adjustment for covariates. Depressive symptoms were not associated with future IGM. Diagnosed diabetes was associated with future elevated depressive symptoms in participants aged 52 to 64 years (OR = 2.17, [95% CI = 1.33-3.56]), but not those 65 years and older (OR = 0.96, [95% CI = 0.59-1.57]) for 4 years of follow-up. Adjustment for covariates partially explained this association. IGM and undiagnosed diabetes were not associated with subsequent elevated depressive symptoms.
  
  
  CONCLUSIONS
  These data suggest that there is a bidirectional association between depressive symptoms and diagnosed diabetes in people aged 52 to 64 years but not in people 65 years and older.
authors: From the Department of Epidemiology and Public Health (P.D., P.Z.), University College London, London, United Kingdom; and Department of Psychology (A.N.), Middlesex University, London, United Kingdom.
authors: Panayotes
authors: P
authors: Demakakos
authors: Paola
authors: P
authors: Zaninotto
authors: Arie
authors: A
authors: Nouwen
mesh_terms: D000367:Age Factors; D000368:Aged; D003863:Depression / Q000150:complications*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000523:psychology; D004739:England / Q000453:epidemiology; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales
chemical_list: D005947:Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human