Selenoprotein P as a Biomarker for Microvascular Complications in Type 2 Diabetes Mellitus: A Cross-Sectional Study...

Background Type 2 diabetes mellitus (T2DM) is a major global health concern, with microvascular complications, neuropathy, retinopathy, and nephropathy contributing substantially to morbidity. Selenoprotein P (SeP), a selenium-transporting antioxidant protein, has been implicated in metabolic dysregulation. This study examined the prevalence of microvascular complications in T2DM and explored their association with circulating SeP levels in a tertiary care center in South India. Materials and methods A cross-sectional study was conducted at Vinayaka Mission's Medical College, Karaikal (2022-2025), enrolling 80 adults with T2DM aged ≥40 years. Neuropathy was assessed using the 10 g monofilament test, retinopathy by fundus examination, and nephropathy by urine albumin-to-creatinine ratio (ACR). Serum SeP was quantified by enzyme-linked immunosorbent assay (ELISA). Analyses used SPSS version 26.0 (IBM Corp., Armonk, NY) with Pearson or Spearman correlation and independent t-test or Mann-Whitney U test, as appropriate. Results Among 80 participants (53.8% women; mean age: 58.84 ± 9.79 years), neuropathy was present in 45% (n = 36), retinopathy in 31.3% (n = 25), and nephropathy in 31.3% (n = 25). The mean SeP was 4.11 ± 1.47 µg/mL and tended to be higher with retinopathy (non-proliferative diabetic retinopathy {NPDR}: 4.52 ± 1.74; proliferative diabetic retinopathy {PDR}: 4.89 ± 1.26) than without (3.98 ± 1.34 µg/mL). Group differences were not statistically significant (retinopathy, p = 0.180; nephropathy, p = 0.187; and neuropathy, p = 0.120). Conclusion Microvascular complications are common in this T2DM cohort. Although not significant, higher SeP levels appeared to parallel retinopathy severity, supporting the further evaluation of SeP as a potential biomarker in larger or longitudinal studies.