Title |
Relationship between Low Free Testosterone Levels and Loss of Muscle Mass
|
---|---|
Published in |
Scientific Reports, May 2013
|
DOI | 10.1038/srep01818 |
Pubmed ID | |
Authors |
Atsumu Yuki, Rei Otsuka, Rumi Kozakai, Itsuko Kitamura, Tomohiro Okura, Fujiko Ando, Hiroshi Shimokata |
Abstract |
We assessed longitudinal relationships between baseline testosterone and muscle mass changes in Japanese men. Data were collected from community-dwelling 957 adult men who participated in a longitudinal study of ageing biennially from 1997-2010. Appendicular muscle mass (AMM) was measured with dual-energy X-ray absorptiometry at baseline and follow-up examinations. The cut-off point of sarcopenia was defined as a skeletal muscle index (AMM/height(2)) < 6.87 kg/m(2). Total testosterone (TT) and free testosterone (FT) were measured with a radioimmunoassay. The calculated FT (cFT) was determined with a formula using albumin, TT, and sex hormone-binding globulin levels. We analyzed 4,187 or 2,010 cumulative data points using generalized estimating equations. Low TT was not associated with sarcopenia. Low cFT (odds ratio = 2.14, 95% confidence interval: 1.06-4.33) and FT (odds ratio = 1.83, 95% confidence interval: 1.04-3.22) were associated with sarcopenia. Low FT may be a predictor of risk for muscle loss in Japanese men. |
X Demographics
Geographical breakdown
Country | Count | As % |
---|---|---|
Australia | 2 | 11% |
United Kingdom | 2 | 11% |
Norway | 1 | 6% |
Netherlands | 1 | 6% |
Indonesia | 1 | 6% |
Japan | 1 | 6% |
United States | 1 | 6% |
Spain | 1 | 6% |
Chile | 1 | 6% |
Other | 1 | 6% |
Unknown | 6 | 33% |
Demographic breakdown
Type | Count | As % |
---|---|---|
Members of the public | 11 | 61% |
Scientists | 5 | 28% |
Practitioners (doctors, other healthcare professionals) | 2 | 11% |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
Japan | 1 | 1% |
Unknown | 69 | 99% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Student > Bachelor | 15 | 21% |
Student > Ph. D. Student | 11 | 16% |
Student > Master | 10 | 14% |
Researcher | 9 | 13% |
Student > Doctoral Student | 6 | 9% |
Other | 10 | 14% |
Unknown | 9 | 13% |
Readers by discipline | Count | As % |
---|---|---|
Medicine and Dentistry | 29 | 41% |
Sports and Recreations | 5 | 7% |
Nursing and Health Professions | 4 | 6% |
Agricultural and Biological Sciences | 4 | 6% |
Biochemistry, Genetics and Molecular Biology | 4 | 6% |
Other | 14 | 20% |
Unknown | 10 | 14% |