The association between serum cystatin C and carotid intima-media thickness in metabolic syndrome patients with normal estimated glomerular filtration rate.

BACKGROUND

We investigated the association between cystatin C and carotid intima-media thickness (CIMT) in patients with metabolic syndrome (MetS) and normal estimated glomerular filtration rate (eGFR).

METHODS

We identified 4895 participants (1112 with MetS vs. 3783 without MetS) with normal eGFR and without prior cardiovascular diseases. The MetS patients were stratified into 4 subgroups (Q1-Q4) by cystatin C quartiles.

RESULTS

MetS patients showed higher cystatin C and CIMT than controls (P<0.001). Among MetS patients, those in higher cystatin C quartiles were more likely to present with increased age, systolic blood pressure, fasting plasma glucose, and CIMT (P<0.01), accompanied with decreased eGFR (P<0.001). After adjusting for age, gender, eGFR, and all components of MetS, cystatin C quartiles were significantly related to the odds ratios. Compared to subgroup Q1, the odds ratios for elevated CIMT were 1.883 (1.259-2.819), 2.194 (1.468-3.279), and 4.164 (2.669-6.497) moving from Q2 to Q4. By ROC analysis, the optimal cystatin C cut-off point was 0.86mg/l for detecting elevated CIMT (sensitivity 60.7%, specificity 69.2%).

CONCLUSIONS

Based on a positive and graded association between cystatin C and CIMT, we assessed that early detection of subclinical atherosclerosis might be necessary in patients with MetS even if at the normal eGFR stage.