Chronic Kidney Disease (CKD) in the U.S. Hemophilia Population: A Cohort Study

Introduction: Over a three-year period, U.S. men with hemophilia were found to be 50 times more likely to die from renal disease than the general population (SMR 50; 95% CI 26.8-92.8) (Soucie et al., Blood 2000). Despite this finding, data regarding chronic kidney disease (CKD) and its risk factors in patients with hemophilia remain limited. The objective of this study is to determine the prevalence of CKD and CKD risk factors among older men with moderate and severe hemophilia. Methods: This CKD cohort study is an extension of a U.S. national study sponsored by the American Thrombosis and Hemostasis Network (ATHN). The study, entitled ATHN 1: A Cross-Sectional Analysis of Cardiovascular Disease (CVD) in the Hemophilia Population, began enrollment in 10/2012. Inclusion criteria are men with moderate or severe congenital hemophilia A or B (FVIII or IX level ≤ 5%), age 54-73. Men with an additional bleeding disorder (besides liver dysfunction) were excluded. In this extension study, CKD risk factors, historical creatinine levels, and history of renal events were obtained from patient interview and chart review after obtaining informed consent. Glomerular filtration rate (GFR) values were calculated using the CKD-EPI equation and compared to values in the general population using the NHANES dataset (Coresh et al., JAMA 2007). CKD is defined as the presence of either kidney damage or decreased kidney function with GFR < 60 ml/min/1.73 m2 for ≥ 3 months, irrespective of cause. Results: As of 6/30/2018, 134/200 planned subjects have been enrolled and interim analysis on 134 subjects from 18 U.S. hemophilia treatment centers (HTCs) is presented here. The majority were white (119; 88.8%) or African-American (13; 9.7%). Mean age was 64 years (SD: 5; range: 56-77). Most used factor on demand, with only 38.8% (52/134) on prophylaxis, defined as ≥2 doses of FVIII or ≥ 1 dose FIX/week. Four (3.0%) had a current inhibitor. Viral infection was common; 28.4% currently had hepatitis C, and 19.4% HIV. Hypertension (HTN) was reported in 51.5% of subjects, 14.9% diabetes mellitus (DM); and average BMI was 28.2 kg/m2 (36.6% obese). 11.6% (16/134) were found to have CVD (defined as angina, MI, TIA, or ischemic or embolic stroke). Acute kidney injury was common. Fasting blood work showed an abnormally elevated creatinine in 26.9% subjects (mean 1.1 mg/dl, SD 0.4). Mean historical maximum creatinine reported in the cohort was 1.0 (range 0.5-4.8), with mean GFR 67 (range 11-126).