Carotid intima-media thickness in children with CKD: results from the CKiD study

Abstract

Background and objectives: In adults, increased carotid intima-media thickness (cIMT) as assessed by ultrasonography is a valid predictor of cardiovascular events. Children with CKD are known to be at increased cardiovascular risk. This study sought to identify cardiovascular risk factors associated with increased cIMT in children with CKD.

Design, setting, participants, & measurements: This was a cross-sectional analysis of cIMT obtained after 12 months of follow-up of 101 children aged 2-18 years with mild to moderate CKD (median GFR 42.9 ml/min per 1.73 m(2)) in the Chronic Kidney Disease in Children cohort study enrolled between April 2005 and September 2009 and 97 healthy pediatric controls between January 2003 and December 2008. An average of six standardized B-mode ultrasound measurements constituted the overall cIMT measurement.

Results: The median cIMT was 0.43 mm (interquartile range, 0.38-0.48) compared with 0.41 mm in healthy controls (P=0.03 for difference). After multivariable adjustment, the median cIMT was 0.02 mm (95% confidence interval [CI], 0.01-0.05) larger than that of the healthy controls. In a multivariable linear regression analysis, dyslipidemia and hypertension were associated with 0.05 mm (95% CI, 0.01-0.08) and 0.04 mm (95% CI, 0.003-0.08) greater mean cIMT, respectively. Body mass index, CKD etiology, GFR, birth weight, pubertal status, calcium, phosphorus, sex, and race were not associated with cIMT.

Conclusions: cIMT is significantly elevated among children with CKD, as is the prevalence of other cardiovascular risk factors. Of these risk factors, hypertension and dyslipidemia are significantly associated with increased cIMT.

Figures

Figure 1.

Box-percentile plots illustrating the distribution of cIMT measurements in 101 Children of the CKiD and in 97 healthy controls. The numerical values of the 50th percentile are shown. The 2.5th, 5th, 10th, 25th, 75th, 90th, 95th, and 97.5th percentiles of the distribution are denoted. cIMT values <2.5th percentile or >97.5th percentile are denoted by closed circles. cIMT, carotid artery intima-medial thickness; CKiD, Chronic Kidney Disease in Children study.