Cytokine Profiles in Patients with Type 2 Diabetes Across Different Durations of the Disease: An Exploratory Cross-Sectional Study

Type 2 diabetes (T2D) is often accompanied by chronic low-grade inflammation, with altered cytokine balance. Although cytokine profiles have often been compared between patients with T2D and healthy individuals, less is known about how they differ among patients with varying disease duration. The aim of this exploratory study was to compare selected pro-inflammatory and anti-inflammatory cytokines in patients with shorter and longer duration of clinically diagnosed T2D. Anonymized surplus serum samples from 18 patients with T2D were analyzed. Patients were divided into two groups according to disease duration: 1–7 years and 8–16 years post-T2D diagnosis. Serum concentrations of six pro-inflammatory cytokines (IL-1β, IL-5, IL-6, IL-8, TNF-α and IFN-γ), three cytokines with anti-inflammatory or immunoregulatory functions (IL-2, IL-4, IL-10), and pro- and anti-inflammatory ratios were measured. All tests were performed using MAGLUMI X8 (Snibe Diagnostics, Shenzhen, China) high-sensitivity chemiluminescent immunoassay according to the manufacturer’s guidelines. Statistical analysis of the data obtained was performed using GraphPad Prism (Boston, MA, USA). The longer-duration T2D group showed higher median concentrations of several pro-inflammatory cytokines, particularly IL-6, IL-8, TNF-α, and IFN-γ, compared with the shorter-duration group. Several values in the longer-duration group exceeded the assay-specific reference intervals provided by the diagnostic platform. Anti-inflammatory and immunoregulatory cytokines showed less consistent differences between groups. Correlation analysis indicated stronger correlations among pro-inflammatory cytokines than among anti-inflammatory or immunoregulatory cytokines. This cross-sectional study suggests that cytokine profiles may differ between patients with shorter and longer durations of T2D, with a pattern consistent with a more pro-inflammatory profile in the longer-duration group. Because of the small sample size, absence of healthy controls, and limited availability of clinical covariates, these findings should be interpreted as descriptive rather than confirmatory and require validation in larger, longitudinal studies with detailed metabolic characterization.