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10. The relative contribution of aging and health status to longitudinal change in hormone profiles: results from the MMAS

Author

Longcope, C. and McKinlay, J.

Subjects
Health, Seniors
Abstract

Studies report that male hormones increase or decrease with aging. However, it is unclear whether it is aging itself, or other factors indirectly associated with aging (for example, weight gain, physical inactivity, chronic diseases, medication usage), that cause such changes. Longitudinal data which examine intrasubject changes are needed. The Massachusetts Male Aging Study (MMAS) enrolled 1,709 men (aged 40-70) in 1985-7 and 7-10 years later re-examined 1,156 (77%) of these same men. Hormones were measured at both time points and were analyzed for longitudinal trend within subjects using both sets of data. Testosterone, free testosterone, and albumin-bound testosterone declined at a rate of 1.6%, 2.8%, and 2.5%, respectively per year explained, in part, by the 1.3% increase per year in the sex hormone-binding globulin levels. Dehydroepiandrosterone declined at a rate of 1.4% similar to that of testosterone, although their sources differ. However, dehydroepiandrosterone sulfate declined at a rate of 5.2% per year. Cortisol levels fell at 0.9% per year which was significant (95% confidence limits-1.2% and-0.7% per year). Thus, there is a decline in adrenal androgen secretion, which is far greater than the decline in cortisol. Testrone and dihydrotestorone (DHT) both increased significantly despite the fall in their precursor androgen. The rise in DHT could be explained in part by the rise in SHBG and the increase in estrone by an increase in peripheral aromatization. The rates, as derived from the longitudinal data, differ in some respects from the cross-sectional analysis of each data set, and might be explained by age related changes in health status.

Published
2002

12. Free estradiol and breast cancer risk in postmenopausal women: Comparison of measured and calculated values

Author

Key, TJ, Appleby, PN, Reeves, GK, Roddam, AW, Dorgan, JF, Longcope, C, Stanczyk, FZ, Stephenson, HE, Falk, RT, Miller, R, Schatzkin, A, Allen, DS, Fentiman, IS, Wang, DY, Thomas, HV, Hankinson, SE, Toniolo, P, Akhmedkhanov, A, Koenig, K, Shore, RE, Zeleniuch-Jacquotte, A, Berrino, F, Muti, P, Krogh, AMV, Sieri, S, Pala, V, Venturelli, E, Secreto, G, Barrett-Connor, E, Laughlin, GA, Kabuto, M, Stevens, RG, Neriishi, K, Land, CE, Cauley, JA, Kuller, LH, Helzlsouer, KJ, Alberg, AJ, Bush, TL, Comstock, GW, Gordon, GB, Miller, SR, and Cancer, EHB

Published
2003

15. Hormones and cognitive function among community-dwelling men: the moderating effect of physical health

Author

Fonda, S., Bertrand, R., Mohr, B., Longcope, C., and McKinlay, J.

Subjects
Health, Seniors
Abstract

Research suggests that men experience hormonal decline with age, with greater declines for men in poor physical health. Research also suggests that certain hormones protect against cognitive decline. Drawing from this research, we tested hypotheses regarding: a) physical health and hormone levels, b) hormone levels and cognition, and c) the hormone-cognition relationship in physically healthy versus unhealthy men. A sample of community-dwelling men aged 40-70 (Massachusetts Male Aging Study) was assessed on three cognitive measures (i.e., WAIS-S Backward Digit, WAIS-R Digit Symbol, Schaie-Thurstone Figural Relations) and four hormone levels (total and free testosterone, estrone, dehydroepiandrosterone sulfate). Results indicate a significant association between lower hormone levels and chronic disease, and higher testosterone levels and higher scores on the Backward Digit Span; however, the effect is stronger for men without chronic disease. This study suggests that some hormones may mitigate cognitive decline in healthy men, but not in men with chronic disease.

Published
2002

16. Does body composition predict rate of change in hormones over time? Results from the MMAS

Author

Derby, C., Morales, K., Longcope, C., and McKinlay, J.

Subjects
Health, Seniors
Abstract

The relation of obesity (BMI > 30 kg/m2), and central adiposity (waist/hip ratio (WHR) > 0.95) to rate of change in hormones over 8-9 years was examined among 934 men in the Massachusetts Male Aging Study with complete anthropometry and hormone data at baseline (1987-1989, ages 40-70) and follow-up (1995-1997). Testosterone, DHEAS, cortisol, estrone, androstenedione and SHBG were assessed using standardized methods. Repeated measures regression was used to analyze trends in hormones in relation to obesity or WHR, adjusting for age, smoking, alcohol, comorbidities, and physical activity. Men with WHR > 0.95 had a steeper decline in total, free and albumin bound testosterone than did men with WHR < 0.95 (time*WHR interaction p < 0.009), while change in testosterone did not vary by obesity level. Obesity and WHR were not related to rate of change in other hormones. Central adiposity may predict accelerated decline in testosterone with age.

Published
2002

17. Caffeine and other predictors of bone density among pre- and perimenopausal women.

Author

Hernández-Avila, Mauricio, Stampfer, Meir J., Ravnikar, Veronica A., Willett, Walter C., Schiff, Isaac, Francis, Marie, Longscope, Christopher, McKinlay, Sonja M., Hernández-Avila, M, Stampfer, M J, Ravnikar, V A, Willett, W C, Schiff, I, Francis, M, Longcope, C, McKinlay, S M, and Longscope C [corrected to Longcope, C ]

Published
1993

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