Posted: Friday, July 15, 2022
Thiazide diuretics are commonly prescribed to treat high blood pressure and account for approximately 30% of all prescriptions for hypertension in the United States and Western Europe. Emerging evidence suggests that the use of thiazide diuretics may increase the risk of skin cancer due to photosensitizing properties that promote the absorption of ultraviolet radiation. However, it is unclear whether the associated risk differs according to skin cancer type. A study, published in Cancers, evaluated the association between thiazide diuretic use and the risk of all skin cancer types.
“Our findings suggest that to promote the rational use of antihypertensive medication, the benefits of thiazide diuretics must be weighed against potential safety concerns in terms of skin cancer risks,” Greg A. Knoll, MD, MSc, FRCPC, of the University of Ottawa, Canada, and colleagues concluded.
The study authors performed a meta-analysis, examining evidence from randomized controlled trials and nonrandomized studies to investigate the association between the use of thiazide diuretics and skin cancer. Overall, 30 nonrandomized studies, including data from up to 19 million individuals, were included in the analysis. Primary outcomes of interest included malignant melanoma and non-melanoma skin cancers. Secondary outcomes included lip cancer, Merkel cell carcinoma, malignant adnexal skin tumors, oral cavity cancer, and precursors of skin cancer.
Although the use of thiazide was minimally harmful, users of thiazide diuretics had a higher risk of developing malignant melanoma (P < .001), basal cell carcinoma (P = .003), and squamous cell carcinoma (P < .001) compared with non-users of these agents. The use of thiazide was also associated with a higher risk of lip cancer (P < .001). The association of thiazide with other secondary outcomes of interest was inconclusive.
Disclosure: The study authors reported no conflicts of interest.