Characteristics of Finasteride Users in Comparison with Nonusers: A Nordic Nationwide Study Based on Individual-Level Data from Denmark, Finland, and Sweden

February 2020 in “ Pharmacoepidemiology and Drug Safety ”

Thora Majlund Kjærulff, Annette Kjær Ersbøll, Eero Pukkala, Kristian Bolin, Anders Green, Martha Emneus, Klaus Brasso, Peter Iversen, Lau Caspar Thygesen

finasteride testicular abnormalities obesity exogenous testosterone radiation exposure diabetes occupational exposure perfume industry high-temperature environments physical inactivity Propecia testosterone

TLDR Finasteride users have higher odds of certain health issues and lower odds of specific lifestyle factors compared to nonusers.

The study compared 246,508 finasteride users (≥35 years) from Denmark, Finland, and Sweden with an equal number of nonusers to identify potential confounders in the association between finasteride use and male breast cancer. Finasteride users had higher odds of testicular abnormalities (OR 1.40), obesity (1.31), exogenous testosterone use (1.61), radiation exposure (1.22), and diabetes (1.07), but lower odds of occupational exposure in the perfume industry or high-temperature environments (0.93), living alone (0.89), living in urban/suburban areas (0.97), and physical inactivity (0.70). The findings highlighted the importance of adjusting for these confounders in studies examining the link between finasteride and male breast cancer.