BACKGROUND & AIMS:

Several studies have shown that chronic hepatitis C (CHC) infection has a negative impact on kidney function, as well as survival, in patients with chronic kidney disease (CKD) or on hemodialysis. The aim of this nationwide registry study was to describe renal disease in Swedish patients with CHC.

METHODS:

In the present study, patients were identified for CHC (B18.2) and CKD (N18) according to the International Classification of Diseases (ICD)-10 in the nationwide Swedish inpatient care day surgery (1997-2013) and non-primary outpatient care (2001-2013) patient registries. Hemodialysis was defined using the procedure code in the non-primary outpatient care. For each patient, up to five non-CHC diagnosed age/sex/place of residency-matched comparators were drawn from the general population at the time of diagnosis. Follow-up started at the date of CHC diagnosis and patients accrued person-time until, whichever came first, death, emigration or December 31st, 2013.

RESULTS:

Between 2001 and 2013, 42,522 patients received a CHC diagnosis. Of these patients, 2.5% (1,077/45,222) were diagnosed with CKD during 280,123 person-years, compared with 0.7% (1,454/202,694) in the matched general population comparators (1,504,765 person-years), resulting in a standardized incidence ratio (SIR) of 4.0. There was a 3.3-7.0-fold risk of patients with CHC requiring hemodialysis. Overall, 17% of patients with CHC receiving hemodialysis were treated for CHC; 24% in the treated cohort died compared with 56% of the untreated cohort (p <0.0001), with antiviral treatment improving survival with an odds ratio of 3.901 (p = 0.001).

CONCLUSIONS:

The results from this nationwide registry study showed that patients with CHC are at a higher risk of developing CKD. Furthermore, hepatitis C treatment seemed to improve survival for patients with CHC on hemodialysis compared with untreated patients.

LAY SUMMARY:

Hepatitis C is an infectious disease that mainly infects the liver, but has also been shown to have negative effects on other organs. This nationwide study demonstrates an increased risk of hepatitis C patients developing reduced kidney function and the need for dialysis. The study also showed improved survival in dialysis patients who received antiviral treatment.