A Significant Correlation Between Lipoprotein(a) Levels and Peripheral Arterial Disease in Patients With Type 2 Diabetes Mellitus: A Retrospective Study

Aims/Background: Lipoprotein(a) [Lp(a)] is recognized as a cardiovascular risk indicator; however, its connection to peripheral arterial disease (PAD) in individuals with type 2 diabetes mellitus (T2DM) is not well established. This research seeks to explore how Lp(a) concentrations relate to the occurrence of PAD in T2DM patients. Methods: A retrospective analysis was conducted on 590 patients diagnosed with T2DM who were admitted to Hefei First People’s Hospital from January 2022 to August 2024. Participants were grouped into tertiles according to their Lp(a) levels. The diagnosis of PAD was made using the ankle-brachial index (ABI), with an ABI <0.9 considered indicative of PAD. The association between Lp(a) concentrations and PAD was examined using multivariate logistic regression models, subgroup analyses, receiver operating characteristic (ROC) curves, and restricted cubic spline (RCS) plotting. Results: Compared to lower Lp(a) levels, the group with higher Lp(a) levels exhibited a higher prevalence of PAD (p = 0.001). Multivariate logistic regression analysis indicated that, after stepwise adjustment for all confounding factors, the risk of PAD in the higher Lp(a) group was 1.961 times that of the lower Lp(a) group (odds ratio [OR] = 1.961, 95% confidence interval [CI]: 1.071–3.588, p = 0.029). Additionally, for each 1 standard deviation increase in Lp(a) or each unit increase in the normalized Lp(a) (Log10Lp(a)), the risk of PAD increased by 25.7% and 80.3%, respectively (OR: 1.257, 95% CI: 1.016–1.555, p = 0.035; OR: 1.803, 95% CI: 1.013–3.209, p = 0.045). Subgroup analysis revealed a stratified association between Lp(a) and PAD risk across multiple subgroups (p < 0.05). ROC analysis demonstrated that Lp(a) had a certain predictive ability for PAD prevalence (area under the curve (AUC): 0.622, 95% CI: 0.568–0.677, p < 0.001). RCS analysis indicated that there was no evidence of a nonlinear relationship between Log10Lp(a) and PAD risk, regardless of the logistic regression model used (p for nonlinearity > 0.05). Conclusion: A significant correlation was observed between elevated Lp(a) levels and an increased risk of PAD in patients with T2DM.