A correlation study of arterial stiffness with P300 event-related potential in non-haemodialytic and haemodialytic chronic kidney disease patients of renal origin

Introduction: Chronic kidney disease (CKD) is associated with hypertension. The renal micro-vessels are vulnerable to the pulsatile nature of systemic pressure leading to arterial stiffness, which may lead to progressive renal disease besides other mechanisms. The stiffened cerebral vasculatures may also cause neural injury. Thus, cognitive impairment is prevalent in CKD patients. However, very few studies have attempted to examine the association of arterial stiffness with P300 event-related potential (P3ERP) in CKD patients of primary renal disease in the Indian population, which forms the basis of the study. Materials and Methods: Twenty-three age- and sex-matched non-haemodialytic and haemodialytic CKD patients were recruited in this cross-sectional and observational study. Montreal cognitive assessment questionnaire was applied to them to estimate global cognitive level. Peripheral and central blood pressure, augmentation index, brachial-ankle pulse wave velocity (baPWV), heart rate and P300 ERP were recorded. Biochemical analysis of the serum was also done. Appropriate statistical tests were performed to compare the differences between the variables of the two groups. Spearman’s Correlation test was performed to examine the relationship between vascular parameters and P300 ERP metrics. Results: Haemodialytic CKD patients exhibit early vascular ageing than non-haemodialytic CKD patients as evidenced by increased heart rate ( P = 0.001) and higher central diastolic ( P = 0.035) and peripheral diastolic blood pressure ( P = 0.042). Although there was no significant difference in latency and amplitude of P300 ERP between the two groups, a significant positive association between baPWV and amplitude of P300 ERP was found. Moreover, higher serum phosphate ( P = 0.021) and uric acid levels ( P = 0.017) in haemodialytic patients promote vascular stiffening. Conclusion: It may be concluded that early vascular ageing in CKD patients occurs due to the interplay of multiple physiological factors, which finally perturb cerebral haemodynamics and are responsible for the cognitive impairment observed in these patients.