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Testosterone in Aging Men; Does men opause exist?. Brad Anawalt, MD University of Washington 12/2/ 11. Not 2 T. 2 T. Testosterone myths. Men undergo men opause ( andropause ) Testosterone is the root of all evil A little testosterone is good, a lot is better. BDA.
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Testosterone in Aging Men; Does menopause exist? Brad Anawalt, MD University of Washington 12/2/11
Not 2 T 2 T
Testosterone myths • Men undergo menopause (andropause) • Testosterone is the root of all evil • A little testosterone is good, a lot is better BDA
Testosterone physiologic effects • Brain: cognition, mood, sex • Skin: hair, healing • Bone: bone growth and strength • Blood: red blood cell production • Muscle: strength • Fat: decreased fat • Immune system: poorly understood BDA
Common symptoms & effects of male hypogonadism • Weakness • Fatigue • Decreased sexual function • Decreased sense of well-being • Depression • Osteoporosis • Loss of facial and body hair • Gynecomastia (↑ breast tissue) BDA
Testosterone pharmacologic effects • Brain: cognition, mood, sex • Bone: bone growth and strength • Blood: red blood cell production • Muscle: strength • Fat: decreased fat BDA
Very-high dosage T bench press in 10 weeks Testosterone dosage = 6-8 times normal NEJM 1996;335:1-7
Epidemiology of ♂ hypogonadism Based on “low” serum T levels alone • < 5% in 20s & 30s • 12% in 50s • 19% in 60s • 28% in 70s • 49% in 80s Harman SM, et al. JCEM. 2001;86:724-731. BDA
Definition of male hypogonadism Syndrome of decreased androgen effect (usually T production) and/or sperm production Diagnosis depends on serum androgens + clinical evidence of inadequate tissue androgen effect BDA
40 30 20 10 0 Age 30-39 40-49 50-59 60-69 70-79 # of men 435 434 333 187 86 Prevalence of Symptomatic ♂ Hypogonadism % Symptomatic Androgen Deficiency Araujo AB, et al. JCEM 2007;92:4241-4247 BDA
Prevalence of Symptomatic ♂ Hypogonadism • Large population study in UK (2010) • Hypogonadism = threshold [T] when symptoms (sexual dysfunction) become increasingly common • Prevalence of hypogonadism is ~ 2% in middle-aged and older men • • ↑ prevalence with ↑ age, obesity & illnesses Wu FW, et al. N Engl J Med 2010;363:123-135. BDA
Effects of aging on the gonadal axis of men • Testes make less testosterone • Hypothalamus & pituitary do not respond normally to lower blood testosterone levels BDA
Feldman HA, et al. J Clin Endocrinol Metab 87:589-598, 2002 D in Reproductive Hormones as ♂ age 1709 ♂ (40-70 years) followed for 7-10 yrs BDA
Wu FCW, et al. J Clin Endocrinol Metab. 2008;93:2737-2745 Obesity & aging synergistically [T] Free [T] (pmol/L) BMI > 30 = 10-15 yr of aging! n = 3200 BDA
Free Testosterone Hypothesis • Free T is the hormonally active form • T bound to SHBG is inactive • T bound to albumin is bioactive (“weakly bound”) • Tissue-mediated dissociation of T from albumin BDA
Testosterone: Younger vs Older Men Normal Young Men Older Men 25% bioavailable 30% tightly bound to SHBG 75% tightly bound to SHBG 70% bioavailable BDA
Common causes of altered SHBG • Low SHBG • Obesity • Diabetes mellitus • Metabolic syndrome • Corticosteroids • Anabolic steroids • Hypothyroidism • High SHBG • Aging • Medications • (anti-epileptics) • Cirrhosis, hepatitis • Estrogens • Hyperthyroidism BDA
> 25% men with low total testosterone levels have normal free testosterone levels
sexual function with T dosage in older ♂ J Clin Endocrinol Metab. 2005;90:3838-3846 BDA
strength with T dosage in ♂ 100 P < 0.001 for dose Young * Old 80 * 60 Δ leg press strength (kg) 40 20 0 -20 25 50 125 300 600 IM T enanthate (mg/week) BDA J Clin Endocrinol Metab. 2005;90:678-688
Risks of T rx for ♂ hypogonadism • Clinical Outcomes • Acne ( in younger ♂) • red blood cell production (in older ♂) • Markers of clinical outcomes • Prostate: small PSA & prostate volume • CV: HDL (“good cholesterol”) • (greater HDL in younger ♂) Male Pattern Blindness BDA
Median serum [T] but no Δ in prostate [T] with im T rx in older hypogonadal ♂ No D in prostatic tissue gene markers related to prostate cancer (Ki67, AR, CD34, PSA) * Setum [T] ng/g Serum [T] ng/dL BDA JAMA. 2006;296:2351-2361
Risks of androgen therapy: cardiovascular disease • Epidemiology: • MI: ♂ > women… BUT • ↑ MI in ♂ with low T vs.♂ with normal T • Change in surrogate markers with testosterone treatment • Mixed effects on lipids • HDL (primarily seen with oral androgens) • Not seen in older ♂ treated with non-oral T • LDL (“bad” cholesterol) • lipoprotein (a) ( another “bad” cholesterol) • Testosterone ↑ coronary vasodilation • Testosterone body fat • Testosterone insulin sensitivity? BDA
Epidemiological data: ↓ [T] = ↑ CAD events • ↓ [T] = ↑ CV and total mortality in study of 794 ♂ followed for up to 20 yrs (mean = 12 yrs) • Laughlin GA, et al. J ClinEndocrinolMetab. 2008;93:68-75. • ↓ [T] = ↑ CV and total mortality in nested case-control study of > 11000 US ♂ surveyed 1993-1997 with 7-year follow-up • Khaw KT, et al. Circulation. 2007;116:2694-2701 • BUT some conflicting data such as… • ↓ [DHT] and [SHBG], but not [T], associated with ischemic heart disease in Male Massachussetts study of > 1600 ♂ followed for > 15 yrs. • Araujo AB, et al. Arch Intern Med. 2007;167:1252-1260 • Recent review: Traish AM, et al. J Androl. 2009;30:477-494. BDA
Androgen ablation therapy may MI & DM • Cohort study of 1372 ♂ with prostate cancer • Earlier fatal MI in ♂ with 6 mos of androgen vs 0 mos • Only true for ♂ > 65 yrs J Clin Oncol 2007;25:2420-2425 • Observational study of > 70,000 ♂ with prostate cancer • DM (HR = 1.34 & orchidectomy & 1.44 for GnRH agonist) • CAD in ♂ treated with GnRH agonist (HR = 1.16) J Clin Oncol 2006;24:4448-56 Biologically plausible: Androgen deprivation = fat, muscle & ? insulin resistance
TOM Trial • Study of 274 elderly ♂ (mean age = 74) • Low [T] • Most had hypertension • ~ 50% obese, 25% diabetes mellitus • 6 months of high dosage testosterone gel or placebo x 1 yr • Results • ↑↑ leg strength with testosterone • ↑ chest strength with testosterone • ↑ speed of walking upstairs with a load • ↑ cardiovascular events with tesosterone • 29 vs. 5 cardiovascular events Bhasaria, et al. N Engl J Med. 2010;363:109-122 BDA
Variation in response to treatment Individual variation • Differences in androgen receptor J ClinEndocrinolMetab. 2007;92:3844-3853 • Differences in metabolism (older ♂ metabolize T slower) J ClinEndocrinolMetab. 2006 • Other differences • e.g., coactivators, repressors, etc BDA
Conclusions • There is no male menopause • Many aging men have low serum [T] levels • May due to poor overall health, obesity • Diagnosis of hypogonadism is tricky in older men • Some men will benefit from testosterone rx • Determining who will benefit …is an art not a science • Different responses based on dose & individual BDA
Differences in dose response with T Rx in younger vs. older ♂ • Benefits • muscle & fat in dose-dependent manner in ♂ of all ages • sexual function in ♂ of all ages • Young ♂ response from low to physiological dosages • Older ♂ response from low to pharmacological dosages • Harms • Lower tolerance for dosages in older ♂ • hct & edema in older ♂ • acne & ↓ HDL in younger ♂ • J ClinEndocrinolMetab. 2005;90:678-688 • J ClinEndocrinolMetab. 2006; • J ClinEndocrinol. 2008;93:914-919 BDA