Psychological and pharmacological interventions for depression in patients with diabetes mellitus: an abridged Cochrane review

Aims: To summarize and critically evaluate the effectiveness of psychological and pharmacological interventions for depression in patients with both diabetes and depression.

Methods: Randomized controlled trials investigating psychological and pharmacological interventions for depression in adults with diabetes and depression were included. A comprehensive search of primary studies according to Cochrane were conducted. Primary outcomes were depression and glycaemic control. Further, treatment adherence, diabetes complications, mortality, healthcare costs and quality of life were investigated. Two reviewers identified primary studies and extracted data independently. Random-effects model meta-analyses were conducted to compute overall estimates of treatment outcomes.

Results: The database search resulted in 3963 references, of which 19 trials were included. Randomized controlled trials of psychological interventions showed positive effects on short- and medium-term depression severity [standardized mean difference short-term range -1.47; -0.14, n = 7; medium-term standardized mean difference -0.42 (95% CI -0.70 to -0.14), n = 3] and depression remission [odds ratio short term 2.88 (95% CI 1.58-5.25), n = 4; odds ratio medium term 2.49 (95% CI 1.44-4.32), n = 2]. Effects on glycaemic control in psychological intervention trials varied substantially (standardized mean difference range -0.97 to 0.47, n = 4). Selective serotonin reuptake inhibitors showed a moderate beneficial effect on short-term depression severity [standardized mean difference -0.39 (95% CI -0.64 to -0.13], n = 5) and depression remission [odds ratio 2.52 (95% CI 1.11-5.75), n = 2]. Glycaemic control improved in randomized controlled trials comparing selective serotonin reuptake inhibitors with placebo at the end of treatment [standardized mean difference -0.38 (95% CI -0.64 to -0.12), n = 5].

Conclusions: Psychological and pharmacological interventions positively affect depression outcomes in patients with diabetes at the end of treatment. Furthermore, short-term glycaemic control improved moderately in pharmacological trials. Most outcomes have not been investigated sufficiently. Moreover, there is a lack of follow-up data for pharmacological trials limiting the evidence on the sustainability of treatment effects.