Subthreshold depression among diabetes patients in Beijing: Cross-sectional associations among sociodemographic, clinical, and behavior factors

Abstract Background This study explores the prevalence of subthreshold depression (SubD) and its association with factors in type 2 diabetes mellitus (T2DM) patients. Methods This cross-sectional study involved 808 outpatients with T2DM from ten hospitals in Beijing between September 2015 and January 2016. All participants completed the Patient Health Questionnaire 9-item (PHQ-9) to evaluate depressive status, with scores between 5 and 14 considered SubD. Conditional logistic regression was conducted to investigate the variables associated with SubD in T2DM patients. Results T2DM patients with SubD comprised 11.6% ( n  = 94) of the sample. The odd ratios for the variables having significant positive associations with SubD were: being a women (OR = 1.90; 95%CI: 1.09–3.32), divorced/widowed (OR = 3.27; 95%CI: 1.46–7.30), comorbidity of cerebrovascular disease (OR = 2.00; 95%CI: 1.06–3.76), more diabetic complications (OR = 8.04; 95%CI: 2.77–23.31), and higher HbA1c in men (OR = 2.41; 95%CI: 1.25–4.64). Being older (OR = 0.78; 95%CI: 0.62–0.98), exercising more (OR = 0.44; 95%CI: 0.22–0.91) and poverty (OR = 0.36; 95%CI: 0.19–0.69) were negatively related to SubD. Limitations The sample was mainly recruited from hospital settings, which limits generalization. The study's cross-sectional design precludes making causal inferences. Conclusions The proportion of SubD was estimated to be 11.6% among T2DM patients in Beijing. Having more diabetic complications and being divorced/widowed made the odds of having SubD 8-fold and 3-fold higher than not having it, respectively. The relationship between SubD and diabetes necessitates early screening for milder forms of depression, which can alleviate the social burden and individual impairment from major depression or other chronic diseases.