Cited by 2,760Hormonal and reproductive studiesHypothalamic control of reproductive hormonesMenopause: Health Impacts and Treatments

The DOI matches its Crossref record, with a small difference in title or year; 67 of the 67 references it cites were found in a registry or an index.

Longitudinal Effects of Aging on Serum Total and Free Testosterone Levels in Healthy Men

Harman, S. Mitchell, Metter, E. Jeffrey, Tobin, Jordan D., Pearson, Jay, Blackman, Marc R.·2001·The Journal of Clinical Endocrinology & Metabolism

Abstract

Many studies have shown cross-sectional (and two small studies, longitudinal) declines in total and/or free testosterone (T) levels, with age, in men. The extent to which decline in T is the result of the aging process per se, as opposed to chronic illness, medication use, and other age-related factors, remains controversial. The frequency with which aging leads to T levels consistent with hypogonadism has also not been defined. These issues bear on the potential use of T replacement in aging men, because aging and hypogonadism have, in common, reduced bone and lean body mass and muscle strength and increased total and abdominal fat. We measured T and sex hormone-binding globulin (SHBG), by RIA, in stored samples from 890 men in the Baltimore Longitudinal Study on Aging. Using a mixed-effects model, we found independent effects of age and date of sampling to reduce T levels. After compensating for date effects, which investigation suggested was artifactual, we observed significant, independent, age-invariant, longitudinal effects of age on both T and free T index (free T index = T/SHBG), with an average change of -0.124 nmol/L.yr and -0.0049 nmol T/nmol SHBG.yr. T, but not free T index, also decreased with increasing body mass index. Use of beta-blocking drugs was associated with higher T and higher free T index levels. Using total T criteria, incidence of hypogonadal T levels increased to about 20% of men over 60, 30% over 70 and 50% over 80 yr of age, and even greater percentages when free T index criteria were employed. Our observations of health factor independent, age-related longitudinal decreases in T and free T, resulting in a high frequency of hypogonadal values, suggest that further investigation of T replacement in aged men, perhaps targeted to those with the lowest serum T concentrations, are justified.

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Metadata

Authors
Harman, S. M., Metter, E. J., Tobin, J. D., Pearson, J., & Blackman, M. R.
Affiliations
  • National Institutes of Health (US)
  • Johns Hopkins University (US)
Venue
The Journal of Clinical Endocrinology & Metabolism
Published
2001-02
Volume
86
Issue
2
Pages
724-731
ISSN
  • 0021-972X (ISSN-L)
  • 1945-7197
OpenAlex
W2139893960
Cited by
2,760
References
67
Citations by year
2026: 63 · 2025: 88 · 2024: 78 · 2023: 83 · 2022: 110 · 2021: 112 · 2020: 116 · 2019: 113 · 2018: 107 · 2017: 153 · 2016: 128 · 2015: 129 · 2014: 138 · 2013: 128 · 2012: 133
FWCI
54.02
Type
journal article
Language
en
Open access
closed
Locations
  • The Journal of Clinical Endocrinology & Metabolism (publishedVersion)
  • PubMed (publishedVersion)
Funders
National Institute on Aging
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Hormonal and reproductive studies
  • Health Sciences › Medicine › Reproductive Medicine › Hypothalamic control of reproductive hormones
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Menopause: Health Impacts and Treatments
Keywords
aging, testosterone, free testosterone, hypogonadism, sex hormone-binding globulin, longitudinal decline, healthy older men, body mass index, beta-blockers, testosterone replacement therapy
MeSH terms
Adult, Aging, Humans, Hypogonadism, Longitudinal Studies, Male, Middle Aged, Radioimmunoassay, Regression Analysis, Sex Hormone-Binding Globulin, Social Class, Testosterone, Baltimore, Reproducibility of Results, White People

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