Prevalence of Renal Impairment and Associated Conditions Among HCV-Infected Persons in the Chronic Hepatitis Cohort Study (CHeCS).

Background: Guidelines for the treatment of HCV-infected persons were updated in August 2015 with new recommendations for patients with renal impairment. Treatment is imperative for patients with severe, renal-associated extrahepatic manifestations of HCV infection.
Aims: We sought to describe the prevalence of these conditions among current HCV-infected patients in a population-based prospective, observational cohort study at four large US health systems.
Methods: Data from cohort patients with chronic HCV infection during 2012 were analyzed for the period from 2006 to 2013. We determined the prevalence of mild to moderately impaired renal function defined as having the most recent estimated glomerular filtration rate [eGFR] ≤ 80 ml/min/1.73 m(2), with severe impairment defined as eGFR < 30 ml/min/1.73 m(2), based on the treatment guidelines. Prevalence of extrahepatic conditions was ascertained using ICD9-codes.
Results: Among 5772 persons, the prevalence of eGFR ≤ 80 was 33 % and eGFR < 30 was 2 %, including among patients with hepatic fibrosis. Diagnosed extrahepatic renal manifestations were rare: vasculitis- 0.2 %, nephrotic syndrome- 0.3 %, and cryoglobulinemia- 0.9 %.
Conclusions: While the prevalence of severe renal impairment and diagnosed extrahepatic manifestations was low, mild-to-moderate renal impairment was common in HCV patients, including those with advanced liver fibrosis for whom the need for treatment is urgent.