Introduction:
Chronic kidney disease (CKD) is a global health problem. Mineral and bone disorders are common in CKD and are now collectively referred to as chronic kidney disease - mineral bone disorder (CKD - MBD). There is a very high cardiovascular morbidity and mortality in CKD patients and atherosclerotic changes are a major contributor to it. Carotid intima media thickness (CIMT) can be measured to assess atherosclerosis and can predict the onset and progression of cardiovascular disease with reasonable accuracy. Although deranged CKD - MBD biochemical parameters are significant risk factors for vascular calcification which is an advanced form of atherosclerosis, it is unclear whether there is any correlation between these parameters with increase in CIMT in CKD patients which is an early form of atherosclerosis. This correlation if present will enable CKD-MBD parameters to be used as surrogate marker for early detection of atherosclerosis and cardiovascular risk in chronic kidney disease patients. This study was done to evaluate for correlation between chronic kidney disease - mineral bone disorder parameters and carotid intima media thickness in chronic kidney disease patients.
Methods:
A hospital based cross-sectional study was conducted on 140 adult patients of CKD stage 3, 4, 5ND (not on dialysis) and 5D (on hemodialysis). Laboratory parameters for CKD-MBD (Calcium, Phosphorus, Vitamin D and PTH) and spot urine protein creatinine ratio were evaluated. Carotid intima media thickness was measured on ultrasound machine. Intima media thickness was taken as distance between leading edge of first echogenic line (lumen intimal interface) and second echogenic line (medial adventitia interface). These measurements were recorded at 0.5 cm, 1cm and 2 cm below bifurcation of common carotid artery on both sides (left and right) . The mean average value of CIMT was calculated for both sides individually followed by calculation of the mean average value of CIMT of both sides together. CKD-MBD parameters (Calcium, Phosphorus, Vitamin D and PTH) and spot urine protein creatinine ratio were correlated with mean average CIMT (both left and right sides together) of total study CKD patients.
Results:
A significant positive correlation was seen between calcium (r=0.525, p<0.0001), phosphorus (r=0.546, p<0.0001), PTH (r=0.550, p<0.0001) and mean average CIMT. Vitamin D (r= -0.145, p=0.088) did not show significant correlation with mean average CIMT. There was significant positive correlation between spot urine protein creatinine ratio and mean average CIMT (r=0.504, p=0.0001). Among comorbidities, diabetes mellitus had a significant positive correlation with CIMT (r=0.168, p=0.047). However hypertension (r= -0.133, p=0.117), dyslipidemia (r= -0.033, p=0.695) and BMI (r=0.074, p=0.383) did not show any significant correlation with CIMT. CIMT had a significant correlation with stage of CKD with its value increasing from stage 3 to stage 4 to stage 5ND (P=0.004).
Conclusions:
In conclusion, CKD-MBD parameters (calcium, phosphorus and PTH) and spot urine protein creatinine ratio may be used as surrogate marker of atherosclerosis and cardiovascular risk in chronic kidney disease patients. Since there is paucity of good quality ultrasound machine and trained ultrasonologists in India (especially remote areas), it may not be always possible to assess carotid intima media thickness. Early assessment and correction of deranged values of CKD-MBD parameters (calcium, phosphorus and PTH) and spot urine protein creatinine ratio can prevent progression of atherosclerosis and thus decrease cardiovascular morbidity and mortality in CKD.
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.