Maximum Carotid Intima-Media Thickness in Association with Renal Outcomes

Aim: We aimed to examine the association between the maximum intima-media thickness of the carotid artery (Max IMT) and renal prognosis, considering their potential interaction with age. Methods: Survival analyses were performed in 112 patients with chronic kidney disease (CKD), to assess renal prognosis, with the endpoint defined as a >= 30% decline in estimated glomerular filtration rate (eGFR) or endstage renal disease. Results: During a median follow-up of 12.5 years, 44 participants reached the study endpoint. The major determinant of Max IMT was the maximum IMT of the internal carotid artery (Max ICA-IMT), which was the distribution ratio of 50.0% of Max IMT. Kaplan-Meier analyses showed that Max IMT >= 1.5 mm was significantly associated with renal prognosis when age and eGFR were matched. On multivariate Cox regression analysis, Max IMT was significantly associated with the renal outcomes and had a significant interaction with the age categories (>= 65 years or < 65 years) (P= 0.0153 for interaction). A 1-mm increase in Max IMT was significantly associated with disease progression in the sub-cohort < 65 years age-category, but not in the >= 65 years age-category; similarly the hazard ratio (HR) in the <65 years age-category was higher than in the >= 65 years age-category (HR: 2.52 vs. 0.95). Comparable results were obtained for Max ICA-IMT, Max bulb-IMT, but not for Max common carotid artery-IMT. Conclusions: A higher Max IMT was a significant renal prognosis factor in patients with CKD aged < 65 years. Our results may provide new insights into treating CKD.