Risk of herpes zoster in patients treated with long-term hemodialysis: a matched cohort study.

BACKGROUND: The risk of herpes zoster in the dialysis population relative to the general population is not known. The aim of this study was to perform a population-based cohort study to investigate the risk of herpes zoster after the initiation of hemodialysis therapy in patients with end-stage renal disease (ESRD) in Taiwan, a country with the highest incidence of ESRD in the world.

STUDY DESIGN: Matched cohort study.

SETTING & PARTICIPANTS: Data were obtained from the Taiwan National Health Insurance Research Database. 843 patients who were beginning hemodialysis therapy in 1999-2003 were included as the study cohort and 3,372 patients without ESRD matched for age and sex were included as a comparison cohort. A multivariate frailty Cox proportional hazard regression model was used to adjust for confounding and compare the 6-year herpes zoster-free survival rate between these 2 cohorts.

PREDICTORS: Hemodialysis.

OUTCOMES: Herpes zoster.

RESULTS: Mean years of follow-up were 4.73 and 5.49 for the hemodialysis and comparison cohorts, respectively. 868 patients developed herpes zoster throughout the study period, 294 from the hemodialysis cohort and 574 from the comparison cohort. The incidence rate of herpes zoster (73.34 events/1,000 person-year) was significantly higher in the hemodialysis cohort than in the control cohort (31.03 events/1,000 person-years). After adjusting for potential confounders, the adjusted HR of herpes zoster was 1.98 (95% CI, 1.72-2.27).

LIMITATIONS: We expect that some patients with mild zoster chose not to seek medical help.

CONCLUSIONS: We conclude that patients treated with long-term hemodialysis are at an increased risk of herpes zoster compared with the general population.