INS and diabetes mellitus: After adjustment for sex, age, hyperlipidemia, hypertension, hs-CRP, BMI, HbA1c, DM duration, eGFR, AER, and the use of insulin and OHAs, a statistically significant association was persistent between plasma GDF-15 concentrations and diabetic retinopathy (OR per 1 SD increment in the log-transformed value, 1.78; 95% CI: 1.05–3.03, p = 0.032).