Weight change and risk of depression in patients with diabetic kidney disease: a nationwide population-based study

Background: Several studies have reported that depression is prevalent in patients with diabetes or chronic kidney disease. However, the relationship between weight changes and the risk of depression has not been elucidated in patients with diabetic kidney disease (DKD).Methods: From the Korean National Health Insurance Service database, we selected 67,866 patients with DKD and body weight data from two consecutive health examinations with a 2-year interval between 2009 and 2012. Weight change over 2 years was cat-egorized into five groups: >=-10%, <-10% to >=-5%, <-5% to < 5%, >= 5% to < 10%, and >= 10%. The occurrence of depression was moni-tored via the codes of International Statistical Classification of Diseases, 10th revision through the end of 2018.Results: During the 5.24-year follow-up, 17,023 patients with DKD developed depression. Weight change and the risk of depression had a U-shaped relationship: patients with >=-10% weight change (hazard ratio [HR], 1.12) and those with >= 10% weight change (HR, 1.11) showed higher HRs for depression than those with <-5% to < 5% weight change, even after adjusting for several confounding factors. In the subgroup analyses, the risk of depression tended to increase as weight gain or weight loss increased in all subgroups.Conclusion: Both weight loss and weight gain increased the risk of depression in patients with DKD.