San Francisco, CA, May 30, 2010–Changes in sex steroid hormone levels may be a cause of lower urinary tract symptoms (LUTS) in older men, according to two studies presented at the 105th Annual Scientific Meeting of the American Urological Association (AUA). LUTS has been linked to metabolic syndrome in the past; emerging research could provide clues about the underlying connection and reasons why men develop these conditions. These data will be presented to the media during a special press conference panel on Sunday, May 30, 2010 at 2 p.m. PDT.
In the first study, researchers from the Republic of Korea studied 278 patients (average age of 62), measuring blood levels of total testosterone, albumin, sex hormone-binding globulin (SHBG), fasting glucose, fasting insulin and high sensitivity C-reactive protein and calculated free testosterone, bioavailable testosterone and homeostasis model assessment of insulin resistance. Researchers measured prostate volume using transrectal ultrasonography and assessed the severity of LUTS using the International Prostate Symptom Score (IPSS). Results showed that testosterone levels were negatively related to IPSS total scores and subscores for voiding symptoms, even after adjusting for age, prostate volume, high sensitivity C-reactive protein and homeostasis model assessment of insulin resistance. Testosterone levels were significantly related to the presence of severe LUTS, even after adjusting for confounding factors.
In the second study, researchers from across the United States studied a randomly selected group of 648 white men, aged 40 to 79 years in 1990 from Olmsted County, MN. Participants completed a questionnaire and a urological exam that included measurement of maximum urinary flow rate and prostate volume in addition to a blood draw. Follow-up exams were conducted every two years through 2007. After analyzing the results, researchers found that testosterone levels fell by a median rate of .19 percent per year and fell even faster among older men. Rapid declines in testosterone were associated with more rapid increases in LUTS and more rapid decreases in maximum flow rates. However, further analyses indicated that the relationship between change in testosterone level and development of LUTS is very complex, and it is important to take into account changes in other sex steroid levels (including estradiol and bioavailable testosterone).
“It’s clear that there may be a link between LUTS and certain hormone deficiencies,” said Anthony Y. Smith, an AUA spokesman. “What is not yet clear is whether these deficiencies are a contributing factor to other metabolic abnormalities.”
NOTE TO REPORTERS: Experts are available to discuss these studies outside normal briefing times. To arrange an interview with an expert, please contact the AUA Communications Office at the number above or e-mail Communications@AUAnet.org.
About the American Urological Association: Founded in 1902 and headquartered near Baltimore, Maryland, the American Urological Association is the pre-eminent professional organization for urologists, with more than 16,000 members throughout the world. An educational nonprofit organization, the AUA pursues its mission of fostering the highest standards of urologic care by carrying out a wide variety of programs for members and their patients.
Wendy Isett, AUA