p-Cresol and cardiovascular risk in mild-to-moderate kidney disease

Cardiovascular disease is highly prevalent in chronic kidney disease. Traditional risk factors are insufficient to explain the high cardiovascular disease prevalence. Free p-cresol serum concentrations, mainly circulating as its derivative p-cresyl sulfate, are associated with cardiovascular disease in hemodialysis patients. It is not known if p-cresol is associated with cardiovascular disease in patients with chronic kidney disease not yet on dialysis. In a prospective observational study in 499 patients with mild-to-moderate kidney disease, we examined the multivariate association between p-cresol free serum concentrations and cardiovascular events. After a mean follow-up of 33 mo, 62 patients reached the primary end point of fatal or nonfatal cardiovascular events. Higher baseline concentrations of free p-cresol were directly associated with cardiovascular events (univariate hazard ratio [HR] 1.79, P