New study. Too bad the study only lasted 1 year. I wonder if the results will be different if it was done over a longer period of time. Personally, I think that dutas and finas do have an effect on bone density…so far this study proves me wrong.
The Effect of 5-Reductase Inhibition With Dutasteride and Finasteride on Bone Mineral Density, Serum Lipoproteins, Hemoglobin, Prostate Specific Antigen and Sexual Function in Healthy Young Men
John K. Amorya, , Bradley D. Anawalta, b, †, Alvin M. Matsumotoa, b, c, ‡, Stephanie T. Pagea, William J. Bremnera, Christina Wangd, e, §, Ronald S. Swerdloffd, and Richard V. Clarkf,
Dutasteride and finasteride are 5-reductase inhibitors that dramatically decrease serum levels of dihydrotestosterone. Because androgens affect bone, lipids, hematopoiesis, prostate and sexual function, we determined the impact of 5-reductase inhibitors on these end points.
Materials and Methods
We conducted a randomized, double-blinded, placebo controlled trial of 99 men 18 to 55 years old randomly assigned to receive 0.5 mg dutasteride (33), 5 mg finasteride (34) or placebo (32) daily for 1 year. Bone mineral density was measured at baseline, after 1 year of treatment and 6 months after drug discontinuation. In addition, markers of bone turnover, fasting serum lipoprotein concentrations, hemoglobin and prostate specific antigen were measured at baseline, after 26 and 52 weeks of treatment, and again 24 weeks after drug discontinuation. Sexual function was assessed at these points by a validated questionnaire.
Significant suppression of circulating dihydrotestosterone levels with the administration of dutasteride or finasteride did not significantly affect bone mineral density or markers of bone metabolism. Similarly serum lipoproteins and hemoglobin were unaffected. Serum prostate specific antigen and self-assessed sexual function decreased slightly during treatment with both 5-reductase inhibitors but returned to baseline during followup.
Profound suppression of circulating serum dihydrotestosterone induced by 5-reductase inhibitors during 1 year does not adversely impact bone, serum lipoproteins or hemoglobin, and has a minimal, reversible effect on serum prostate specific antigen and sexual function in normal men. Circulating dihydrotestosterone does not appear to have a clinically significant role in modulating bone mass, hematopoiesis or lipid metabolism in normal men.