Association between inflammatory biomarkers and depressive symptoms among diabetes mellitus and diabetic retinopathy: A cross-sectional study

This study aimed to compare patients with diabetes mellitus (DM) and diabetic retinopathy (DR), analyze the relationship between inflammatory biomarkers and depressive symptoms, and further explore the role path of weight management. Data were attained from National Health And Nutrition Examination Survey 2011 to 2020. We calculated the neutrophils-lymphocytes ratio (NLR), systemic inflammatory response index (SIRI), aggregate index of systemic inflammation (AISI) and systemic immune inflammation index (SII). A generalized linear model was used to examine the influence of NLR, SIRI, AISI, and SII on depressive symptoms among DM and DR and the influence of body mass index (BMI) and waist circumference (WC) on depressive symptoms among DR. The mediation effect model was employed to examine the relationship between inflammatory biomarkers, BMI, WC and Patient Health Questionnaire-9 scores among DM. Among 2584 participants with diabetes, 2069 (80.07%) were without retinopathy and 515 (19.93%) were diagnosed with DR, NLR, SIRI, AISI, and SII were risk factors for depressive symptoms among DM (odds ratio [OR] = 1.236, 95% confidence interval [CI] = 1.080–1.415, P = .002; OR = 1.369, 95% CI = 1.155–1.623, P < .001; OR = 1.001, 95% CI = 1.000–1.002, P < .001; OR = 1.001, 95% CI = 1.000–1.001, P = .003). WC fully mediated the relationship between NLR and Patient Health Questionnaire-9 among adults with DM, with effect coefficients of 0.028 (95% CI = 0.005–0.059). BMI and WC were risk factors for depressive symptoms among DR (OR = 1.115, 95% CI = 1.043–1.192, P = .001; OR = 1.044, 95% CI = 1.014–1.074, P = .004). Inflammatory biomarkers are the risk factors of depressive symptoms only in adults with DM, but not in DR. Among adults with DM, we should pay attention to monitoring the level of inflammation and reduce WC instead of BMI, while in DR patients, controlling BMI and WC is an effective strategy to prevent and control depressive symptoms.