The association between hydrochlorothiazide use and non-melanoma skin cancer in kidney transplant recipients

Abstract Background hydrochlorothiazide (HCTZ) diuretics were correlated with an increased risk of Non-Melanoma Skin Cancer (NMSC) and melanoma in the general population. Information is a scarce regarding this effect in Kidney transplant recipients who are at increased risk of skin malignancies under immunosuppression. Methods Single center retrospective analysis of adult kidney transplant recipients between January 1, 2010, and December 31, 2015. The primary outcome of the study was the first diagnosis of skin cancer that was removed and pathologically analyzed. Exposure to thiazides was defined as HCTZ use daily for at least one year at a dose of 12.5 mg. Results Among 520 kidney transplant recipients, 50 (9.4%) were treated with HCTZ. During a median follow-up of 9.8 years, 67 patients underwent surgical removal and pathological analysis of at least one skin cancer. Exposure to HCTZ during the three years following transplantation was associated with an increased risk of skin cancer (p=0.004). In a multivariate model, there was a significant association between HCTZ exposure and NMSC (HR 2.54, 95%CI 1.26-5.15, p=0.007). There was a higher rate of Basal Cell Carcinoma (BCC) with HCTZ exposure, according to both univariate and multivariate analyses (HR 2.61, 95%CI 1.06-6.43, p=0.037) and (HR 3.03, 95%CI 1.22-7.55, p=0.017, respectively). However, no significant association was observed between HCTZ exposure and Squamous Cell Carcinoma (SCC). Conclusions These findings suggest a benefit of increased frequency of dermatologist inspection in kidney transplant recipients receiving HCTZ especially in increased UV exposure area.