Association between symptoms of depression and glycaemic control may be unstable across gender

Aims Lloyd and colleagues (Diabetic Med 2000; 17, 198-202) have described an association between poor glycaemic control and moderate to severe depression in male but not in female diabetes patients. However, the validity of this study may be limited by its small sample size and the influence of uncontrolled confounders. Therefore, we set out to replicate this study by investigating the associations between depression and glycaemic control in larger samples, while controlling for potential confounders. Methods Out-patients with diabetes (n=174) and 1437 patient members of the Dutch Diabetes Association (DDA) completed the Hospital Anxiety and Depression Scale. Demographic and clinical characteristics were obtained using medical records (out-patients) or self-report (DDA). Results After controlling for number of complications, years of education and body mass index, depression showed significant, low positive correlations with HbA(1c) in three of the four female samples and in one of the four male samples. Only for out-patients with Type 2 diabetes was the correlation between HbA(1c) and depression significantly higher for women when compared with men (0.19 vs. 0.04; P=0.02). Conclusions The association between depression and HbA(1c) may be stronger in women with Type 2 diabetes. Oestrogen levels and self-care behaviours may play a mediating role in this association. Further research is required before we can conclude that the association between symptoms of depression and glycaemic control differs across gender.