This article is more than 5 years old. Information may no longer be current.
Common erectile dysfunction medication may increase melanoma risk
Click Here to Manage Email Alerts
The use of phosphodiesterase type 5 inhibitors for erectile dysfunction produced a small but significant increase in the risk for malignant melanoma, according to the results of a population-based study.
However, more data are needed to determine if this association is causal, according to the researchers.
Phosphodiesterase type 5 (PDE5) inhibitors — oral agents for erectile dysfunction — target part of a pathway associated with the development of malignant melanoma. Further, recent studies linked the use of sildenafil to an increased risk for melanoma, according to study background.
Stacy Loeb, MD, MSc, assistant professor of urology and population health at New York University, and colleagues conducted a nationwide, population-based, case-controlled study to observe the association between melanoma risk and PDE5 inhibitor use in Sweden.
The analysis included data from 4,065 men (median age, 69 years) with melanoma diagnosed in Sweden between 2006 and 2012 and 20,325 cancer-free men (median age, 70 years).
The researchers collected data from the Swedish Prescribed Drug Register, the Swedish Melanoma Register and other demographic databases and health care registers.
By matching year of birth, the researchers assigned five random controls per patient. Separate analyses analyzed risk based on the type of PDE5 inhibitor used — including sildenafil, tadalafil or vardenafil — and disease stage at diagnosis.
Of the 4,065 men with melanoma, 11% (n = 435) had filled prescriptions for PDE5 inhibitors. Eight percent (n = 1,713) of the control population also filled prescriptions for PDE5 inhibitors.
Results of a multivariable analysis indicated men taking PDE5 inhibitors experienced an increased risk for melanoma (OR = 1.21; 95% CI, 1.08-1.36). A particularly high increased risk occurred among men who filled a single prescription (exposure rate, 4% for cases vs. 3% for controls; OR = 1.32; 95% CI, 1.1-1.59).
However, men who filled two to five prescriptions (4% vs. 3%; OR = 1.14; 95% CI, 0.95-1.37) or six or more prescriptions (3% vs. 2%; OR = 1.17; 95% CI, 0.95-1.44) did not experience an increased melanoma risk.
The researchers observed a significant association between the use of PDE5 inhibitors and a diagnosis of melanoma at stage 0 (13% for cases vs. 8% for controls; OR = 1.49; 95% CI, 1.22-1.83) or stage I (12% vs. 10%; OR = 1.21; 95% CI, 1.02-1.43). However, significant associations did not occur for a diagnosis at stage II to stage IV.
The increased risk for melanoma associated with PDE5 inhibitors was comparable among men who took sildenafil (OR = 1.14; 95% CI, 0.99-1.31) compared with men who took vardenafil or tadalafil (OR = 1.16; 95% CI, 0.99-1.37). In a separate analysis, a significant association with melanoma risk occurred among men who only used sildenafil (OR = 1.26; 95% CI, 1.08-1.48) and men who only used vardenafil or tadalafil (OR = 1.3; 95% CI, 1.08-1.57).
The researchers also observed an increased risk for basal cell carcinoma among men who took PDE5 inhibitors (9% for cases vs. 8% for controls; OR = 1.19; 95% CI, 1.14-1.25).
The researchers acknowledged the study underrepresented younger men. Further, the researchers did not include data relevant to melanoma risk, including skin type, history of sunburn, previous travel and family history.
“Overall, the pattern of association raises questions about whether this association is causal,” Loeb and colleagues concluded. “Rather, the observed association may reflect confounding by lifestyle factors associated with both PDE5 inhibitor use and low-stage melanoma.” – by Cameron Kelsall
Disclosure: Loeb reports personal fees from Bayer and Sanofi-Aventis. Other researchers report personal fees from AstraZeneca, Ferring and Pfizer.
Click Here to Manage Email Alerts