Diabetes incidence associated with depression and antidepressants in the Melbourne Longitudinal Studies on Healthy Ageing (MELSHA).
OBJECTIVE
Diabetes may be associated with depression and antidepressant medication (ADM) use, but published findings remain equivocal. The authors' aimed to determine the risk of diabetes incidence associated with baseline depression exposures (symptoms and/or ADM use).


METHODS
A prospective cohort study was conducted in a regionally representative sample of non-institutionalised older Australian people (N = 1000, aged 65 + year), who were followed up biennially between 1994 and 2004 (attrition was approximately 24%). Analyses excluded participants for prevalent diabetes at baseline, determined by self-report or specific medications. Diabetes incidence was ascertained by first self-report at any follow-up wave. Depression exposures (baseline predictors) were defined by the Psychogeriatric Assessment Scales (PAS) depression scale and ADM use, and classified as: (1) 'symptomatic' (PAS score 5+); (2) 'ADM use'; (3) 'symptomatic or ADM use'; (4) 'symptomatic and no ADM use'; (5) 'asymptomatic (PAS score <5) and ADM use' and (6) 'symptomatic and ADM use'. Covariates were demographic, lifestyle, functional health and chronic disease factors. Cox regressions were used to determined hazard ratios with 95% confidence intervals (HR [95% CI]) for diabetes incidence according to depression exposures, adjusted for significant covariates.


RESULTS
Baseline response rate was 70.3%. Depression predictors of diabetes incidence were 'symptomatic' (2.29 [1.28,4.10]), 'symptomatic or ADM use' (2.13 [1.32,3.44]) and 'symptomatic and no ADM use' (2.38 [1.28,4.45]), after adjustment for significant covariates. Being asymptomatic was not a protective factor among those prescribed antidepressants.


CONCLUSIONS
Older people with depressive symptoms are at least twice more likely to develop diabetes than those without depressive symptoms, regardless of antidepressants.
Atlantis
Evan
E
Ageing, Work, and Health Research Unit, Faculty of Health Sciences, The University of Sydney, Sydney, Australia. evan.atlantis@adelaide.edu.au
Browning
Colette
C
Sims
Jane
J
Kendig
Hal
H
D000368:Aged; D000369:Aged, 80 and over; D000928:Antidepressive Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001315:Australia / Q000453:epidemiology; D015331:Cohort Studies; D003863:Depression / Q000188:drug therapy / Q000453:epidemiology* / Q000523:psychology; D003920:Diabetes Mellitus / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D015577:Geriatric Assessment; D005852:Geriatric Psychiatry; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors
D000928:Antidepressive Agents