Journals of Gerontology Series A: Biological Sciences and Medical Sciences Large Type Edition
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Kenny, A. M.
Right arrow Articles by Prestwood, K. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kenny, A. M.
Right arrow Articles by Prestwood, K. M.
The Journals of Gerontology Series A: Biological Sciences and Medical Sciences 57:M321-M325 (2002)
© 2002 The Gerontological Society of America

Effects of Transdermal Testosterone on Cognitive Function and Health Perception in Older Men With Low Bioavailable Testosterone Levels

Anne M. Kennya, Sandra Bellantonioa, Cynthia A. Grumanb, Ruben D. Acostaa and Karen M. Prestwooda

a Center on Aging, University of Connecticut Health Center, Farmington
b Braceland Center for Mental Health and Aging, Institute of Living/Hartford Hospital, Connecticut

Anne M. Kenny, Center on Aging, MC-5215, University of Connecticut Health Center, Farmington, CT 06030-5215. Email: kenny@nso1.uchc.edu


   Abstract
Top
 Abstract
Methods
 Results
 Discussion
 References
 
Background. Many men older than 50 years have bioavailable testosterone levels below the reference range for young adult men. The impact of the decreased androgen levels on cognition and health perception has received little attention.

Methods. Sixty-seven men (mean age 76 ± 4 years, range 65–87) with bioavailable testosterone levels below 128 ng/dl (lower limit for adult normal range) were randomized to receive transdermal testosterone (2–2.5 mg patches/d) or placebo patches for 1 year. All men received 500 mg supplemental calcium and 400 IU vitamin D. Outcome measures included sex hormones [testosterone, bioavailable testosterone, sex hormone binding globulin (SHBG), estradiol, and estrone], cognitive tests (Digit Symbol, Digit Span, Trailmaking A and B), health perception (Medical Outcome Survey Short-form 36 or SF-36), lower extremity muscle strength and power, and calcium intake.

Results. Twenty-three men (34%) withdrew from the study; 44 men completed the trial. Bioavailable testosterone levels increased from 93 ± 34 (SD) to 162 ± 100 ng/dl (p < .002) at 12 months in the testosterone group (n = 24) while no change occurred in the control group (n = 20). While there was no change in estradiol levels in either group, estrone levels increased in the testosterone group (28 ± 7 to 32 ± 9 pg/dl, p = .017). Scores on the Digit Symbol test improved in both the testosterone and placebo groups. Scores on Trailmaking B improved in men treated with testosterone (p < .005), although the changes were not statistically different from the changes seen in the placebo group. Twelve-month scores on Trailmaking B for the entire group were correlated with 12-month testosterone levels (p = .016). Scores for health perception measured by SF-36 did not change significantly, though scores of mental and general health declined in both groups during the 12-month intervention. Twelve-month bioavailable testosterone scores were directly correlated with scores for physical role (p = .022), vitality (p = .036), and the physical composite score (p = .010).

Conclusions. Transdermal testosterone treatment in men with low bioavailable testosterone levels does not impair and may improve cognitive function. Treatment did not improve health perception but this may have been due to the side effects of skin irritation suggested by similar reactions in both the testosterone and placebo groups.

MANY men older than the age of 50 have bioavailable testosterone levels below the normal young adult range. There is a progressive decrease in bioavailable testosterone levels with increasing age and further declines associated with medical comorbidity (1)(2)(3). The significance of the gradual decline in testosterone levels on cognition and health perception has received little attention. In animal studies, testosterone replacement reverses memory loss and decreases amyloid precursor protein production (4)(5). Young hypogonadal men with low testosterone levels have impaired cognitive function, compared with eugonadal men, that improved following testosterone replacement (6). Similarly, in studies of younger men with severe testosterone deficiency, testosterone levels and spatial cognition are inversely associated (7)(8)(9)(10)(11). While few studies exist in older men, higher testosterone levels were predictive of performance in several domains of cognition (12)(13), and testosterone supplementation improved performance on spatial cognition and verbal and working memory compared to placebo in three small studies (14)(15)(16).

Health perceptions related to testosterone replacement have not been extensively investigated in older men. Young hypogonadal men reported decreased irritability, tiredness, anxiety, and sadness and increased energy level, cheerfulness, and sense of well being on testosterone replacement (17)(18). Similarly, untreated young men with hypogonadism reported higher scores for anger, fatigue, and confusion than eugonadal control subjects (19). However, no association has been found between health perception and baseline testosterone levels in other studies (18)(20), including studies of older men (21). In studies of men receiving testosterone replacement, no changes in health perception have been detected in men with testosterone levels 1 SD below the young adult mean (22) or in men with normal testosterone levels (23).

This study is part of a larger study to assess the effects of testosterone on bone and muscle (24) and in addition, we sought to determine the effects of transdermal testosterone supplementation on cognition and health perception in men older than 65 years with low levels of bioavailable testosterone. We hypothesized that transdermal testosterone replacement would improve cognitive function and health perception in older men compared with placebo.


   Methods
Top
 Abstract
 Methods
Results
 Discussion
 References
 
Study Population and Design
Men were recruited to take part in a study to determine the effects of testosterone on bone and muscle (24). As part of that study, we also measured cognition and health perception. Information on recruitment and eligibility are described elsewhere (24). A total of 67 men were enrolled in the study.

Men were randomized to receive 12 months of treatment with either transdermal testosterone supplementation (5 mg/d) using the nonscrotal testosterone patch or a placebo patch; all men received 500 mg of calcium and 400 IU of cholecalciferol. We measured total and bioavailable testosterone, sex hormone binding globulin (SHBG), estrone, and estradiol, and we administered the Medical Outcome Survey Short-form 36 (SF-36) and standardized tests of cognitive function (Digit Symbol, Digit Span, Trailmaking A, Trailmaking B) at baseline and 12 months. We assessed skin effects of the transdermal patch and symptoms of itching using a 5-point scale (0 = no rash; 4 = erythema, induration, and bullae) and a 4-point scale (1 = none; 4 = persistent), respectively (25).

Biochemical Assays
Total and bioavailable testosterone and SHBG measurements were performed at Endocrine Sciences Inc., Calabasas Hills, California. Testosterone levels were measured by radioimmunoassay, SHBG by competitive binding assay, and bioavailable testosterone by competitive binding of the non-SHBG-bound portion of testosterone following ammonium sulfate precipitation of the SHBG-bound steroid as described by Nankin (26). Estradiol and estrone were performed using radioimmunoassay (Diagnostic Systems Lab, Inc., Webster, TX).

Statistical Analysis
Baseline and clinical characteristics were reported using means and standard deviations stratified by treatment group. One-way analysis of variance (ANOVA) or chi-square analysis was used to test the difference in baseline characteristics between the treatment groups. Wilcoxon signed ranks test was used to assess change within groups over time, and ANOVA was used to compare the percent change in health perception or cognitive scores between groups. Multiple linear regression analysis was performed using 12-month scores of the domains of the SF-36, controlling for baseline scores, as the dependent variable; these domains included physical function, role-physical, bodily pain, general health, vitality, social function, role-emotional, and mental health. The changes in cognitive test scores from baseline to 12 months were also entered as dependent variables, including change in Digit Scan, Digit Symbol, Trailmaking A, and Trailmaking B scores. Independent variables in the regression models were those variables found to correlate with the dependent variables; variables entered into the correlation matrix included sex hormone levels, physical activity, strength, and skin effect (rash and itching) scores. All analyses were done using SPSS version 10.0 (SPSS, Inc., Chicago, IL).


   Results
Top
 Abstract
 Methods
 Results
Discussion
 References
 
Sixty-seven men were randomized to treatment. Twenty-three men (33%) discontinued due to rash (n = 4), elevation in prostate specific antigen level (n = 5), intercurrent illness (n = 9), and personal reasons (n = 5) with no significant differences between the groups. Forty-four men completed the study: 24 men in the testosterone group and 20 men in the placebo group. The baseline characteristics of the study sample are presented in Table 1 ; no significant differences existed in baseline information between the treatment and control groups.


View this table:
[in this window]
[in a new window]
  		Table 1. Baseline Characteristics of 44 Men Selected for Low Testosterone Levels Completing 1 Year of Testosterone or Placebo Supplementation

 
Following treatment, bioavailable testosterone increased in the testosterone group from 93 ± 34 ng/dl to 162 ± 100 ng/dl (p = .002) and was unchanged in the placebo group (101 ± 26 ng/dl, p = .86). Estrone levels increased from 28 ± 7 pg/dl to 32 ± 9 pg/dl (p = .017) in the testosterone treatment group but did not change in the placebo group (p = .12). There were no significant changes in SHBG or estradiol in either group.

Results of cognitive testing are summarized in Table 2 . Digit Symbol test scores improved in both groups. Trailmaking B scores improved in the testosterone group compared to baseline (p < .01). No changes were found in scores on Trailmaking B in the placebo group, and no significant difference could be detected between scores from the testosterone and placebo groups (p = .19). After controlling for baseline scores, the change in Trailmaking B score in the entire group was significantly associated with 12-month testosterone levels by linear regression analysis (R2 = .18, p = .016).


View this table:
[in this window]
[in a new window]
  		Table 2. Comparison of Cognitive Test Scores Prior to and Following 12 Months of Testosterone or Placebo Treatment

 
SF-36 scores are shown in Table 3 . Overall, there were few changes in health perception. Significant declines in the general and mental health domains are seen in both groups, and the changes were similar. Twelve-month bioavailable testosterone levels predicted 12-month scores for role-physical (R2 = .39, p = .022), vitality (R2 = .17, p = .036), and physical component composite (R2 = .17, p = .010) by linear regression analysis, after controlling for baseline scores. In similar analysis, the 12-month score for bodily pain, after correcting for baseline score, was negatively associated with itching score (R2 = .08, p = .05).


View this table:
[in this window]
[in a new window]
  		Table 3. Comparison of Scores on Individual Domains of Health Perception Measured by Medical Outcome Survey Short-Form 36 Prior to and Following 12 Months of Testosterone or Placebo Treatment

 
There were no significant differences in rash irritation between the testosterone groups (1.9 ± 0.3 vs 0.8 ± 0.2; p = .09), but 77% of the men in the testosterone group compared with 40% of men in the placebo group reported a score of 2 or greater, signifying a rash with induration. Itching was more frequent in the men in the testosterone group compared with the placebo group (3.2 ± 0.2 vs 2.6 ± 0.2, p = .001).


   Discussion
Top
 Abstract
 Methods
 Results
 Discussion
References
 
Treatment with testosterone did not result in overall changes in cognition compared with placebo, though significant improvements from baseline scores were detected on the Trailmaking B test. The inability to detect differences in Trailmaking B scores between the testosterone and placebo groups may have been due to the small sample size. However, an association between the 12-month testosterone levels and the changes in scores of the Trailmaking B test suggests that our results are not spurious. Others who used Trailmaking B in their evaluations have not found differences or changes associated with testosterone levels or supplementation, but the study populations were not selected for low testosterone levels and are not directly comparable with our study (12)(14). Trailmaking B is a test that requires both right and left cerebral hemisphere and overall general brain functions for integration (27)(28). Testosterone deficiency may impair performance on this test, although this theory has not been directly tested. Testosterone may also exhibit its effect indirectly via estrogen after aromatization. Estrone increased following testosterone supplementation in our study while Janowsky and colleagues report a decrease in estrogen levels following testosterone replacement (14). An inverse relationship between estrogen levels and spatial cognition has been found in several studies of women (29).

There is evidence of cognitive improvement associated with higher testosterone levels in the literature. Barrett-Connor and Goodman-Gruen, in a population-based study of 547 older men, found that older men with higher bioavailable testosterone levels had better scores on tests of verbal memory and mental control (12). Morley and colleagues similarly found bioavailable testosterone levels correlate with cognitive abilty including tests of visual and verbal learning, memory, and naming ability (13). Janowsky and colleagues found that testosterone supplementation improved spatial cognition, but the improvement was more closely associated with the decrease in estradiol levels possibly due to central inhibition of gonadotropins; no differences were found between groups in verbal memory, speeded cognitive flexibility, or fine motor dexterity (14). In another study by Janowsky and Chavez (15), working memory improved after 1 month of testosterone supplementation to scores of young men. Cherrier and colleagues also reported significant improvement in spatial and verbal memory in testing during intramuscular testosterone replacement (16). In contrast, Sih and colleagues (30) found no change in memory in a small group of older hypogonadal men receiving testosterone. Our work does not answer the question of whether or by what mechanism testosterone affects neurocognitive function but suggests, along with the work of Janowsky and colleagues and Cherrier and colleagues, that further study of the role of testosterone on cognition in older men is warranted.

The men in this study reported baseline health perception by SF-36 scores comparable to those of age- and gender-matched subjects (31). These results are similar to other reports of self-perceived health in older men with both normal and low testosterone levels (21) and older men with low bioavailable testosterone levels (22)(23).

We expected testosterone supplementation to improve health perception due to reports of improved mood and energy following testosterone supplementation in young, hypogonadal men (17)(18). However, two aspects of health perception, general health and mental health, declined over 12 months in both the placebo and treatment groups. Others, similarly, have found no improvement in health perception following testosterone or dihydrotestosterone replacement in older men (22)(23)(32). The decline in health perception scores may be due to the decline in health perception reported with increasing age (31), though this is unlikely given the relatively short duration of our study. More likely, testosterone replacement may be associated with improved health perception only in states of severe deficits as seen in studies of younger, hypogonadal men. Further studies are required to understand whether testosterone replacement is associated with better health perception in this population.

Another explanation for the lack of effect of testosterone therapy on self-perceived health may be due to the delivery system. Both the testosterone and placebo patches were associated with skin irritation (40% in placebo group and 77% in testosterone group) and itching. Itching predicted self-perceived bodily pain at the 12-month survey, suggesting that the rash and itching induced by the placebo and testosterone patches may be responsible for the overall lack of improvement in health perception and for the deterioration in self-perceived general and mental health in our study sample. There has been another report of decline in quality-of-life scores in a study involving allergic symptom induction (33). Other studies of transdermal testosterone or dihydrotestosterone delivery have also failed to demonstrate change in health perception (22)(32), but one study of 13 older, hypogonadal men receiving intramuscular testosterone reported a general increase in sense of well-being (34) while another study of eugonadal men did not (23). Again, further studies of testosterone supplementation using various delivery systems are needed to determine whether there are associated changes in health perception and whether they are dependent on the mode of delivery.

Bioavailable testosterone levels at 12 months predicted some aspects of health perception, including self-perceived role limitations due to physical problems and self-perceived vitality, as well as the physical component composite score. This suggests that testosterone levels in older men may positively influence health perception associated with perceived physical function. Snyder and colleagues also reported improved self-perceived physical functioning in men receiving testosterone compared with placebo (22). Testosterone has been implicated in the process of sarcopenia and in the associated loss of muscle mass and strength (35), although we did not find that strength predicted self-perceived physical function scores. Further studies to understand the mechanism by which testosterone predicts physical function, other than by strength, are required.

The study has several limitations. The sample size is small with a large number of men discontinuing prior to study completion. This may have biased the results to only the most robust individuals answering questions. While baseline measures of changes in cognitive function were only compared in the men who completed the study, we may have missed an effect in less cognitively robust men. Similar effects may have been missed in relation to health perception.

Transdermal testosterone treatment in men with low bioavailable testosterone levels does not impair and may improve cognitive function. Treatment did not improve health perception, but this may have been due to the side effects of skin irritation suggested by similar reactions in both the testosterone and placebo groups. Further studies of testosterone supplementation will be required to fully address the role of testosterone in cognition and health perception in older men with testosterone decline.


   Acknowledgments
 
This work has been supported by the Patrick and Catherine Donaghue Research Foundation, General Clinical Research Center (MO1-RR06192), Claude Pepper OAIC (5P60-AG13631), and Dr. Kenny has been supported with fellowships from the Brookdale Foundation and the Paul Beeson Faculty Scholar Program. In addition, we thank Pamela Fall and Christine Abreu for assistance in running the biochemical assays and Julie Fenster for assistance with data management. Testosterone and placebo patches were provided by SmithKline Beecham at no charge to the study.

Received November 29, 2001

Accepted December 10, 2001


   References
Top
 Abstract
 Methods
 Results
 Discussion
 References
 

  1. Korenman SG, Morley JE, Mooradian AD, et al. 1990. Secondary hypogonadism in older men: its relation to impotence. J Clin Endocrinol Metab. 71:963-969. [Abstract]
  2. Khosla S, Melton LJ, Atkinson EJ, O'Fallon WM, 2001. Relationship of serum sex steroid levels to longitudinal changes in bone density in young versus elderly men. J Clin Endocrinol Metab. 86:3555-3561. [Abstract/Free Full Text]
  3. Morley JE, Kaiser FE, Perry HM, et al. 1997. Longitudinal changes in testosterone, luteinizing hormone, and follicle-stimulating hormone in healthy older men. Metabolism. 46:410-413. [Medline]
  4. Flood JF, Morley PM, Morley JE, 1995. Age-related changes in learning, memory, and lipofuscin as a function of the percentage of SAMP8 genes. Physiol Behav. 58: (4) 819-822. [Medline]
  5. Gouras GK, Xu H, Gross RS, et al. 2000. Testosterone reduces neuronal secretion of Alzheimer's beta-amyloid peptides. Proc Natl Acad Sci USA. 97: (3) 1202-1205. [Abstract/Free Full Text]
  6. Alexander GM, Swerdloff RS, Wang C, et al. 1998. Androgen-behavior correlations in hypogonadal men and eugonadal men. II. Cognitive abilities. Horm Behav. 33: (2) 85-94. [Medline]
  7. Vogel W, Broverman DM, Klaiber EL, Abraham G, Cone FL, 1971. Effects of testosterone infusions upon EEGs of normal male adults. Electroencephalogr Clin Neurophysiol. 31: (4) 400-403. [Medline]
  8. Kertzman C, Robinson DL, Sherins RJ, Schwankhaus JD, McClurkin JW, 1990. Abnormalities in visual spatial attention in men with mirror movements associated with isolated hypogonadotropic hypogonadism. Neurology. 40:1057-1063. [Abstract/Free Full Text]
  9. Cappa SF, Guariglia C, Papagno C, et al. 1988. Patterns of lateralization and performance levels for verbal and spatial tasks in congenital androgen deficiency. Behav Brain Res. 31: (2) 177-183. [Medline]
  10. Christiansen K, Knussmann R, 1987. Sex hormones and cognitive functioning in men. Neuropsychobiology. 18: (1) 27-36. [Medline]
  11. Gouchie C, Kimura D, 1991. The relationship between testosterone levels and cognitive ability patterns. Psychoneuroendocrinology. 16: (4) 323-334. [Medline]
  12. Barrett-Connor E, Goodman-Gruen D, 1999. Cognitive function and endogenous sex hormones in older women. J Am Geriatr Soc. 47: (11) 1289-1293. [Medline]
  13. Morley JE, Kaiser F, Raum WJ, et al. 1997. Potentially predictive and manipulable blood serum correlates of aging in the healthy human male: progressive decreases in bioavailable testosterone, dehydroepiandrosterone sulfate, and the ratio of insulin-like growth factor 1 to growth hormone. Proc Natl Acad Sci USA. 94:7537-7542. [Abstract/Free Full Text]
  14. Janowsky J, Oviatt K, Orwoll E, 1994. Testosterone influences spatial cognition in older men. Behav Neurosci. 108: (2) 325-332. [Medline]
  15. Janowsky J, Chavez B, 2000. Sex steroids modify working memory. J Cognitive Neuroscience. 12: (3) 407-414.
  16. Cherrier MM, Asthana S, Plymate S, et al. 2001. Testosterone supplementation improves spatial and verbal memory in healthy older men. Neurology. 57: (1) 80-88. [Abstract/Free Full Text]
  17. O'Carroll R, Bancroft J, 1984. Testosterone therapy for low sexual interest and erectile dysfunction in men: a controlled study. Br J Psychiatry. 145:146-151. [Abstract/Free Full Text]
  18. Wang C, Alexander G, Berman N, et al. 1996. Testosterone replacement therapy improves mood in hypogonadal men—a clinical research center study. J Clin Endocrinol Metab. 81:3578-3583. [Abstract]
  19. Burris A, Banks S, Carter S, Davidson J, Sherins R, 1992. A long-term, prospective study of the physiologic and behavioral effects of hormone replacement in untreated hypogondal men. J Androl. 13:297-304. [Abstract/Free Full Text]
  20. Anderson RA, Bancroft J, Wu FCW, 1992. The effects of exogenous testosterone on sexuality and mood of normal men. J Clin Endocrinol Metab. 75:1503-1507. [Abstract]
  21. Dunbar N, Gruman C, Reisine S, Kenny A, 2001. Comparison of two health status measures and their associations with testosterone levels in older men. Aging Male. 3:1-7.
  22. Snyder PJ, Peachey H, Hannoush P, et al. 1999. Effect of testosterone treatment on bone mineral density in men over 65 years of age. J Clin Med Endocrinol. 84:1966-1972.
  23. Reddy P, White CM, Dunn AB, Moyna NM, Thompson PD, 2000. The effect of testosterone on health-related quality of life in elderly males— a pilot study. J Clin Pharm Ther. 25:421-426. [Medline]
  24. Kenny AM, Prestwood KM, Gruman CA, Marcello KM, Raisz LG, 2001. Effects of transdermal testosterone on bone and muscle in older men with low bioavailable testosterone levels. J Gerontol Med Sci. 56A:M266-M272. [Abstract/Free Full Text]
  25. Meikle AW, Arver S, Dobs AS, Sanders SW, Rajaram L, Mazer NA, 1996. Pharmacokinetics and metabolism of a permeation-enhanced testosterone transdermal system in hypogonadal men—influence of application site—a clinical research center study. J Clin Endocrinol Metab. 81: (5) 1832-1840. [Abstract]
  26. Nankin HR, Calkins JH, 1986. Decreased bioavailable testosterone in aging normal and impotent men. J Clin Endocrinol Metab. 63:1418-1420. [Abstract]
  27. Reitan RM, 1955. The relation of the Trail Making Test to organic brain damage. J Consulting Psychol. 19:393-394.
  28. Reitan RM, 1958. The validity of Trail Making Test as an indicator of organic brain damage. Percept Mot Skills. 8:271-276.
  29. Hampson E, 1995. Spatial cognition in humans: possible modulation by androgens and estrogens. J Psychiatry Neurosci. 20: (5) 397-404. [Medline]
  30. Sih R, Morley JE, Kaiser FE, Perry HM, III Patrick P, Ross C, 1997. Testosterone replacement in older hypogonadal men: a 12-month ran-domized controlled trial. J Clin Endocrinol Metab. 82: (6) 1661-1667. [Abstract/Free Full Text]
  31. Ware JE. SF-36 Health Survey Manual and Interpretation Guide. Boston, MA: The Health Institute, New England Medical Center; 1993.
  32. Ly LP, Jimenez M, Zhuang TN, Celermajer DS, Conway AJ, Handelsman DJ, 2001. A double-blind, placebo-controlled, randomized clinical trial of transdermal dihydrotestosterone gel on muscular strength, mobility, and quality of life in older men with partial androgen deficiency. J Clin Endocrinol Metab. 86: (9) 4078-4088. [Abstract/Free Full Text]
  33. Ellis A, Day J, Lundie M, 1999. Impact on quality of life during an allergen challenge research trial. Ann Allergy Asthma Immunol. 83:33-39. [Medline]
  34. Tenover JS, 1992. Effects of testosterone supplementation in the aging male. J Clin Endocrinol Metab. 75: (4) 1092-1098. [Abstract]
  35. Morley JE, 2001. Editorial—Andropause: is it time for the geriatrician to treat it?. J Gerontol Med Sci. 55A:M489-M491.



This article has been cited by other articles:


Home page
 JAMAHome page
M. H. Emmelot-Vonk, H. J. J. Verhaar, H. R. Nakhai Pour, A. Aleman, T. M. T. W. Lock, J. L. H. R. Bosch, D. E. Grobbee, and Y. T. van der Schouw
Effect of Testosterone Supplementation on Functional Mobility, Cognition, and Other Parameters in Older Men: A Randomized Controlled Trial
JAMA, January 2, 2008; 299(1): 39 - 52.
[Abstract] [Full Text] [PDF]

Home page
 J AndrolHome page
C. Vaughan, F. C. Goldstein, and J. L. Tenover
Exogenous Testosterone Alone or With Finasteride Does Not Improve Measurements of Cognition in Healthy Older Men With Low Serum Testosterone
J Androl, November 1, 2007; 28(6): 875 - 882.
[Abstract] [Full Text] [PDF]

Home page
 Arch NeurolHome page
P. H. Lu, D. A. Masterman, R. Mulnard, C. Cotman, B. Miller, K. Yaffe, E. Reback, V. Porter, R. Swerdloff, and J. L. Cummings
Effects of Testosterone on Cognition and Mood in Male Patients With Mild Alzheimer Disease and Healthy Elderly Men
Arch Neurol, February 1, 2006; 63(2): 177 - 185.
[Abstract] [Full Text] [PDF]

Home page
 NeurologyHome page
C. N. Lessov-Schlaggar, T. Reed, G. E. Swan, R. E. Krasnow, C. DeCarli, R. Marcus, L. Holloway, P. A. Wolf, and D. Carmelli
Association of sex steroid hormones with brain morphology and cognition in healthy elderly men
Neurology, November 22, 2005; 65(10): 1591 - 1596.
[Abstract] [Full Text] [PDF]

Home page
 NeurologyHome page
M. M. Cherrier, A. M. Matsumoto, J. K. Amory, S. Ahmed, W. Bremner, E. R. Peskind, M. A. Raskind, M. Johnson, and S. Craft
The role of aromatization in testosterone supplementation: Effects on cognition in older men
Neurology, January 25, 2005; 64(2): 290 - 296.
[Abstract] [Full Text] [PDF]

Home page
 J. Gerontol. A Biol. Sci. Med. Sci.Home page
J. E. Morley
Editorial. Mobility Performance: A High-Tech Test for Geriatricians
J. Gerontol. A Biol. Sci. Med. Sci., August 1, 2003; 58(8): M712 - 714.
[Full Text] [PDF]

Home page
 J. Gerontol. A Biol. Sci. Med. Sci.Home page
J. E. Morley
The Need for a Men's Health Initiative
J. Gerontol. A Biol. Sci. Med. Sci., July 1, 2003; 58(7): M614 - 617.
[Full Text] [PDF]

Home page
 J. Gerontol. A Biol. Sci. Med. Sci.Home page
J. E. Morley and H. M. Perry III
Androgens and Women at the Menopause and Beyond
J. Gerontol. A Biol. Sci. Med. Sci., May 1, 2003; 58(5): M409 - 416.
[Full Text] [PDF]

Home page
 J. Gerontol. A Biol. Sci. Med. Sci.Home page
W. A. Banks and J. E. Morley
Memories Are Made of This: Recent Advances in Understanding Cognitive Impairments and Dementia
J. Gerontol. A Biol. Sci. Med. Sci., April 1, 2003; 58(4): M314 - 321.
[Full Text] [PDF]

Home page
 J. Gerontol. A Biol. Sci. Med. Sci.Home page
S. H. Tariq MD
KNOWLEDGE ABOUT LOW TESTOSTERONE IN OLDER MEN
J. Gerontol. A Biol. Sci. Med. Sci., April 1, 2003; 58(4): M382 - 383.
[Full Text] [PDF]

Home page
 J. Gerontol. A Biol. Sci. Med. Sci.Home page
J. E. Morley
Editorial: Hot Topics in Geriatrics
J. Gerontol. A Biol. Sci. Med. Sci., January 1, 2003; 58(1): M30 - 36.
[Full Text] [PDF]

Home page
 J. Gerontol. A Biol. Sci. Med. Sci.Home page
J. E. Morley
Editorial: Citations, Impact Factor, and the Journal
J. Gerontol. A Biol. Sci. Med. Sci., December 1, 2002; 57(12): M765 - 769.
[Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Kenny, A. M.
Right arrow Articles by Prestwood, K. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kenny, A. M.
Right arrow Articles by Prestwood, K. M.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
All GSA journals The Gerontologist
Journals of Gerontology Series B: Psychological Sciences and Social Sciences