Low-density lipoprotein cholesterol predicts coronary artery calcification events in patients with type 2 diabetes: a longitudinal study

Coronary Artery Calcification (CAC) is a major risk factor for various cardiovascular diseases. Low-Density Lipoprotein Cholesterol (LDL-C) is a significant factor in atherosclerotic cardiovascular diseases and is usually elevated in patients with Type 2 Diabetes Mellitus (T2DM). However, the association between LDL-C levels and incident CAC in asymptomatic T2DM patients remains unclear. This study is a single-center retrospective cohort study conducted from January 2018 to December 2023, including 2,631 asymptomatic T2DM patients who underwent regular health screenings. All participants were confirmed to be free of CAC at baseline by computed tomography (CT). Based on baseline LDL-C levels, participants were divided into three groups (T1: 0.66–2.43 mmol/L; T2: 2.44–3.18 mmol/L; T3: 3.19–7.21 mmol/L). The follow-up endpoint was the occurrence of incident CAC, with a total follow-up period of 72 months. Kaplan-Meier survival curves were used for analysis, followed by log-rank tests. Univariate and multivariate Cox proportional hazards regression models were employed to investigate the relationship between LDL-C and incident CAC, and subgroup analysis was performed to test the robustness of the LDL-C and CAC relationship. During a median follow-up period of 29.9 months, 885 (33.64%) participants developed incident CAC occurred. The cumulative incidence of incident CAC increased progressively with higher LDL-C levels (log-rank test, P < 0.001). After adjusting for confounding factors, multivariable Cox proportional hazards regression results showed a significant association between LDL-C and incident CAC (hazard ratio [HR], 1.77; 95% confidence interval [CI], 1.64–1.92). When LDL-C was treated as a categorical variable, elevated levels in T2 (adjusted HR, 1.62; 95% CI, 1.36–1.93; P < 0.001) and T3 (adjusted HR, 3.38; 95% CI, 2.84–4.03; P < 0.001) were significantly associated with the risk of incident CAC. Additionally, subgroup analysis demonstrated a consistent association between LDL-C and incident CAC. High LDL-C levels are associated with incident CAC in asymptomatic T2DM patients, suggesting that LDL-C may be useful for risk stratification in this population.