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.
7 citations,
March 2019 in “Cancer Epidemiology, Biomarkers & Prevention” Finasteride use is not clearly linked to an increased risk of male breast cancer.
8 citations,
December 2017 in “Cancer Medicine” Finasteride use may increase the risk of male breast cancer.
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3 citations,
February 2016 in “Scandinavian journal of urology” Finasteride use varies among Denmark, Finland, Norway, and Sweden, with higher usage in Finland and Sweden.
28 citations,
August 2014 in “Cancer Causes & Control” Taking 5α-reductase inhibitors does not significantly increase the risk of breast cancer in men.
32 citations,
May 2013 in “The Journal of Urology” Using finasteride or dutasteride does not increase the risk of male breast cancer.
14 citations,
January 2018 in “Advances in Clinical Chemistry” The document concludes that hormonal biomarkers are key for diagnosing hyperandrogenemia in women and hypogonadism in men.
77 citations,
June 2015 in “Nature Reviews Urology” Some common medications can harm male fertility, but many effects can be reversed.
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58 citations,
March 2013 in “Human Reproduction Update” Products should be called 'sperm-safe' only after thorough, well-designed tests.
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