II. Definitions
- Andropause (Age-Associated Hypogonadism in Men)
- Primary sexual and reproductive changes in aging male
III. Epidemiology
- Age of onset: 40-70 years old
- Decline typically starts after age 40 years old
- Prevalence in U.S. (1990): 35 Million men
- Prevalence in U.S. (predicted for 2010): 54 Million men
- Testosterone decreases after age 30 years
- Testosterone is deficient in 86% of men by age 80
IV. Physiology: Changes with aging
- Erection
- Ejaculation
- Decreased force of ejaculation
- Decreased awareness of ejaculation
-
Testosterone
-
Serum Testosterone decreases for age over 50 years
- Hypogonadism in 20% of men over age 60 years
- Hypogonadism in 50% of men over age 80 years
- Testosterone Levels drop 1% per year ages 40-70 years
-
Serum Testosterone decreases for age over 50 years
- Body Composition
- Decreased Lean Body Mass/decreased strength
- Upper and central body fat increases with age
V. Findings
VI. Labs
- See Male Hypogonadism
- Total Serum Testosterone <300 ng/dl (in the morning, or 2 within 2 hours of awakening)
- Ruled out if Testosterone >400 ng/dl
- Recheck a second value to confirm low Testosterone
-
Free Testosterone (Bioavailable Testosterone) testing indications
- Most accurate measure
- Low SHBG (Obesity, Type II Diabetes, Hypothyroidism)
- High SHBG (Older age)
- Wide variation in accuracy among labs
- Consider evaluation for secondary cause
- See Testicular Failure
- Always obtain serum pituitary markers when Serum Testosterone is <150 ng/dl (expert endocrinology opinion)
- Indications to evaluate for pituitary tumor
- Serum Prolactin high
- Serum LH low
- Serum FSH low
- Consider other conditions causing low Testosterone
- Obstructive Sleep Apnea
- Major Depression
- Significant acute illness
- References
- Young (2012) Mayo POIM Conference, Rochester
- Bhasin (2010) J Clin Endocrinol Metab 95(6):2536-59 [PubMed]
VII. Associated Conditions
- Osteoporosis
- Associated with Major Depression
VIII. Management: Androgen Replacement
- See Androgen Replacement
- Precautions
- Androgen Replacement is not FDA approved for typical age related Testosterone decrease
- Approved for other causes of Male Hypogonadism (e.g. Chemotherapy, infection, Pituitary Lesion)
- Transdermal agents are preferred
- Baseline exam prior to starting replacement
- See Androgen Replacement
- Digital Prostate exam
- Prostate Specific Antigen (PSA)
- Complete Blood Count (or Hematocrit)
IX. References
- Ayta (1999) BJU 84(1):50-6 [PubMed]
- Gray (1991) J Clin Endocrinol Metab 73:1016 [PubMed]
- Kaiser (1999) Med Clin North Am 83(5):1267-78 [PubMed]
- Lewis (2001) Urol Clin North Am 28(2):209-16 [PubMed]
- Morales (2000) J Urol 163:705-12 [PubMed]
- Petering (2017) Am Fam Physician 96(7): 441-9 [PubMed]
- Schow (1997) Postgrad Med 101(3):62-79 [PubMed]
- Sternbach (1998) Am J Psychiatry 155(10):1310-8 [PubMed]