Aim: We aimed to study the relationship of elevated C reactive protein (CRP) levels (1.0-2.9 or ≥3.0 mg/L) with carotid intima-media thickness (IMT) in Chinese adults with normal low-density lipoprotein (LDL) cholesterol (<100 mg/dL).
Methods: Cross-sectional analysis was performed using 2499 eligible subjects recruited from a single community in Shanghai in 2008. These subjects were divided into three groups according to their serum CRP levels (<1.0 mg/L, 1.0-2.9 and ≥3.0 mg/L). IMT was measured using a high-resolution tomographic ultrasound system.
Results: As compared to CRP <1.0 mg/L (n= 1994), subjects with CRP 1.0-2.9 (n=265) and ≥3.0 mg/L (n= 240) were much older and had higher body mass index, waist circumference, systolic and diastolic blood pressure, hemoglobin A1c and serum triglycerides; IMT was significantly elevated in CRP ≥3.0 or 1.0-2.9 mg/L (0.66 or 0.65 vs 0.61 mm, p<0.0001). Subjects with CRP ≥3 mg/L were associated with 1.45-fold risk for elevated IMT (≥0.7 mm) (95% confidence interval, 1.02-2.06) after full adjustment. The association was more prominent in subjects with aged <60 (odds ratio (OR)= 2.04; p= 0.04), in diabetic patients (OR= 1.79; p= 0.04) and obese subjects (OR= 1.55; p= 0.006).
Conclusions: Increased CRP is associated with elevated IMT in Chinese adults with normal LDL. Low-grade inflammation plays an independent and important role in atherosclerosis.