Depression compromises diabetes treatment in juveniles, and this study aimed to identify influential targets most likely to improve adherence to treatment and glycemic control. Prospective observational studies investigating associations between depression and treatment adherence in juveniles with type 1 diabetes were extracted from MEDLINE, EMBASE, CINAHL, PsycINFO and Cochrane Central. Nineteen studies comprising 2,935 juveniles met our criteria. Median effect sizes between depression and treatment adherence were 0.22 (interquartile range (IQR), 0.16–0.35) by patient and 0.13 (IQR, 0.12–0.24) caregiver report. Corresponding values for depression/glycemic control were 0.16 (IQR, 0.09– 0.23) and 0.08 (IQR, 0.04–0.14), respectively. Effect sizes varied with study design, publication year and assessment tools: CES-D yielded a higher effect size than other assessment tools for depression, where associations for depression and either adherence or glycemic control was investigated. Several behaviours influenced adherence and glycemic control.
Conclusion: This study showed moderate associations between depression and poor treatment adherence. Targeting behaviour and social environments, however, may ultimately provide more cost-effective health gains than targeting depressive symptoms.