Efficacy of antihistamines on mortality in patients receiving maintenance hemodialysis: an observational study using propensity score matching

Antihistamines are widely used to treat pruritus in patients receiving hemodialysis. In a previous cross-sectional study, we reported an association between antihistamine use and the absence of eccentric cardiac hypertrophy in patients receiving hemodialysis. Therefore, in this study, we sought to evaluate the efficacy of antihistamines on all-cause and cardiovascular mortality in patients receiving hemodialysis according to our outpatient dialysis database. We used a propensity score matching method. Among the 389 patients receiving hemodialysis according to our database, we extracted those taking antihistamines and matched them with patients not taking antihistamines using propensity scores based on 38 variables. All-cause mortality and cardiovascular mortality were estimated by the Kaplan-Meier method, and a log-rank test was used to examine the differences between the survival curves. We included 154 patients, or 77 matched pairs, from the entire cohort (c-statistic = 0.78, p < 0.0001). There were no differences in any background factor between the antihistamine and non-antihistamine group. During the mean observational period of 5.4 years, 50 patients died, and the all-cause mortality rate was 27.3% (21 patients) in the antihistamine group and 37.3% (29 patients) in the non-antihistamine group (p = 0.0314). The cardiovascular mortality rate was 16.9% (13 patients) in the antihistamine group and 25.9% (20 patients) in the non-antihistamine group (p = 0.0417). The results of this study suggest that all-cause and cardiovascular mortality improved with antihistamine use in patients receiving hemodialysis. However, the clinical efficacy of antihistamines needs to be confirmed in a prospective randomized study in the future.