Association of hydrochlorothiazide treatment compared with alternative diuretics with overall and skin cancer risk: a propensity-matched cohort study

Use of fixed-dose combinations for cardiovascular indications from 2018 to 2023: a nationwide population-based study

AIMS

Clinical guidelines support the use of fixed-dose combinations (FDC) for prevention of cardiovascular disease. Implementation of FDC into clinical care remains challenging, and current population-based data are scarce.

METHODS AND RESULTS

Claims data on dispensed drugs in an outpatient care setting of approximately 87% of the German population were analysed regarding the use of FDC according to time, age of the insured persons, and active ingredients. The overarching trend for all FDC revealed a decrease from 77.3 defined daily doses per 1000 statutory health-insured (SHI) persons per day (DID) in the second half-year of 2018 (2018HY02) to 60.8 DID in the first half-year of 2023 (2023HY01) (Spearman ρ = -0.988; P < 0.001). The total DID for all antihypertensives (AHT) increased from 590.6 in 2018HY02 to 624.8 in 2023HY01 (ρ = 0.855; P = 0.002), but the DID for fixed-dose AHT (AHT-FDC) declined from 74.1 in 2018HY02 to 55.0 in 2023HY01 (ρ = -0.988; P < 0.001). Conversely, the use of all lipid-lowering agents (LLA) and LLA-FDC continuously increased: The total DID of all LLA rose from 92.5 in 2018HY02 to 134.4 in 2023HY01 (ρ = 1.000; P = 0.000), and for LLA-FDC from 3.1 in 2018HY02 to 5.5 DID in 2023HY01 (ρ = 0.915; P < 0.001). AHT-FDC and LLA-FDC were less frequently dispensed to patients at least 80 years than to patients less than 80 years. Dispensing of multiple purpose FDC increased from 2018HY02 to 2023HY01 from 0.11 DID to 0.26 DID (ρ = 1.000; P = 0.000) but remained negligible.

CONCLUSION

Use of AHT-FDC in Germany is declining. In contrast, FDC containing LLA are increasingly prescribed. Dispensing of multiple purpose FDC is very low. Strategies are needed to facilitate the use of FDC as recommended by current guidelines.

Phototoxic Reactions Inducted by Hydrochlorothiazide and Furosemide in Normal Skin Cells-In Vitro Studies on Melanocytes and Fibroblasts

Hypertension is known to be a multifactorial disease associated with abnormalities in neuroendocrine, metabolic, and hemodynamic systems. Poorly controlled hypertension causes more than one in eight premature deaths worldwide. Hydrochlorothiazide (HCT) and furosemide (FUR), being first-line drugs in the treatment of hypertension, are among others the most frequently prescribed drugs in the world. Currently, many pharmacoepidemiological data associate the use of these diuretics with an increased risk of adverse phototoxic reactions that may induce the development of melanoma and non-melanoma skin cancers. In this study, the cytotoxic and phototoxic potential of HCT and FUR against skin cells varied by melanin pigment content was assessed for the first time. The results showed that both drugs reduced the number of metabolically active normal skin cells in a dose-dependent manner. UVA irradiation significantly increased the cytotoxicity of HCT towards fibroblasts by approximately 40% and melanocytes by almost 20% compared to unirradiated cells. In the case of skin cells exposed to FUR and UVA radiation, an increase in cytotoxicity by approximately 30% for fibroblasts and 10% for melanocytes was observed. Simultaneous exposure of melanocytes and fibroblasts to HCT or FUR and UVAR caused a decrease in cell viability, and number, which was confirmed by microscopic assessment of morphology. The phototoxic effect of HCT and FUR was associated with the disturbance of redox homeostasis confirming the oxidative stress as a mechanism of phototoxic reaction. UVA-irradiated drugs increased the generation of ROS by 10-150%, and oxidized intracellular thiols. A reduction in mitochondrial potential of almost 80% in melanocytes exposed to HCT and UVAR and 60% in fibroblasts was found due to oxidative stress occurrence. In addition, HCT and FUR have been shown to disrupt the cell cycle of normal skin cells. Finally, it can be concluded that HCT is the drug with a stronger phototoxic effect, and fibroblasts turn out to be more sensitive cells to the phototoxic effect of tested drugs.

A randomized, placebo-controlled, trial to assess the photosensitizing, phototoxic and carcinogenic potential of hydrochlorothiazide in healthy volunteers

BACKGROUND AND AIMS

Pharmacovigilance reports, associating hydrochlorothiazide (HCT) with skin cancer, resulted in a significant decrease of HCT prescriptions for hypertension and heart failure. Whether HCT exhibits phototoxic properties thereby causing skin cancer remains unknown. This study aimed to examine the photosensitizing, phototoxic and carcinogenic potential of HCT in a randomized, placebo-controlled, double-blind trial in vivo and also in vitro .

METHODS

The trial assigned 30 healthy, normotensive adult volunteers in a 2:1 ratio to either HCT 25 mg/day or placebo for 15 days. Photosensitivity of the skin with and without the effect of HCT treatment were assessed. Following whole-body ultraviolet A (UVA) and B (UVB, 311 nm) irradiation, phototoxic and carcinogenic reactions by measuring urinary excretion of pyrimidine dimers were evaluated. For the in-vitro studies, human keratinocytes (HaCaT) were incubated with HCT, irradiated with UVB, and analysed for markers of inflammation, apoptosis and carcinogenesis.

RESULTS

Skin photosensitivity following exposure to UVA and UVB remained unchanged from baseline to 15-day follow-up in both groups (UVA change HCT 0.0 J/cm 2 vs. placebo 0.0 J/cm 2 ; P  = 0.99; UVB change HCT 0.0 J/cm 2 vs. placebo -0.2 J/cm 2 ; P  = 0.06). Pyrimidine dimers were not detected in either group. In vitro , combination of HCT and UVB irradiation did not induce the expression of oxidative stress marker proteins, inflammatory proteins, apoptotic proteins or activation of oncoproteins.

CONCLUSION

HCT did not increase photosensitivity for UVA or UVB in healthy volunteers compared with placebo, and was not associated with phototoxic or carcinogenic reactions. In vitro , HCT was also not associated with phototoxicity or carcinogenesis (NCT04654312).