Familiality of Cardiovascular Mortality in End-Stage Renal Disease Patients

Abstract

A very high rate of cardiovascular (CV) death is well recognized in individuals with end-stage renal disease (ESRD). Besides many other factors, this excess risk may also be related to familiality. We tested this hypothesis by estimating the risk of CV death among both ESRD patients and their relatives. In this case-control study, we used the Utah Population Database (UPDB), which includes genealogy records, state-wide death certificates as well as other data sets. These have been linked to the University of Utah Health Sciences Enterprise Data Warehouse which provides multiple diagnosis data sources. Patients with ESRD either on dialysis or who received a kidney transplant were identified in the clinical databases at the University of Utah Dialysis Program and Kidney Transplant Program or from Utah death certificates. CV deaths were identified by the reporting on the death certificates. The relative risks for CV death, adjusted for several potential confounders in the ESRD patients (n = 516) and in their first-degree (n = 2,418) and second-degree (n = 7,720) relatives were estimated in relation to the general population. Using information from death certificates, ESRD patients were found to have disproportionately increased risk for CV mortality (relative risk or RR = 2.4; 95% CI 2.11–2.72), compared to the general population. First-degree relatives of ESRD patients were also found to have an increased CV mortality risk (RR = 1.10; 95% CI 1.01–1.20). When the specific categories of CVD were analyzed, the first-degree relatives also had higher risks for death from acute myocardial infarction (RR = 1.20; 95% CI 1.03–1.40) or heart failure (RR = 1.32; 95% CI 1.12–1.56). An increased risk for CV mortality was, however, not observed in second-degree relatives of ESRD patients, except for the subcategory of hypertensive heart disease (RR = 1.24, 95% CI 1.01–1.49). In conclusion, this study suggests that, in addition to many putative risk factors, the increased risk of CV death in ESRD patients may have a familial contribution.