Diabetes mellitus and risk of subsequent depression: a longitudinal study

Int J Nurs Stud. 2012 Apr;49(4):437-44. doi: 10.1016/j.ijnurstu.2011.09.019. Epub 2011 Oct 7.


Background: Findings of previous studies on the association between diabetes and the risk of depression are contradictory. Furthermore, much less is known concerning the association among young adults.

Objective: To investigate whether diabetes is associated with an increased risk of subsequent development of depression, with emphasis on age-specific variations.

Design: A cohort study.

Setting: Claims data of one million subjects randomly selected from 23 million people covered by the Taiwan National Health Insurance program.

Participants: From the claims data, we identified 14,048 patients aged ≥ 20 years with newly diagnosed diabetes in 2000-2002 and randomly selected 55,608 non-diabetic subjects for comparison, that were frequency-matched by calendar year, age, and gender. Incidence rates of depression to the end of 2007 were identified, and risks were compared between the two groups.

Results: The incidence of depression was 1.80-times higher in the diabetic group than in nondiabetic subjects over a median follow-up of 6.5 years (adjusted hazard ratio [HR]=1.46, 95% confidence interval [CI]: 1.24-1.71). Age-specific HRs for incidence of depression in relation to diabetes were not statistically different between the patient subgroups aged 20-39, 40-49, 50-59, 60-69 and ≥ 70 years (p value for age-diabetes interaction=0.33). Stratified analyses showed that the association was much stronger for subjects without comorbid cardiovascular disease than for those with this comorbidity. Insulin treatment was associated with a 43% reduced risk of depression in diabetic patients.

Conclusions: In this population-based study, diabetic patients were at a higher risk for subsequent depression. Adequate treatment reduced the risk.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Depression / complications*
  • Diabetes Complications*
  • Humans
  • Incidence
  • Longitudinal Studies
  • Middle Aged
  • Risk Factors