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ABSTRACT
Androgenetic alopecia is a stressful experience for both sexes, but possibly more distressing for women. Relative to female controls, women with androgenetic alopecia have more social anxiety, poorer self-esteem and psycho-social well-being, less of a sense of control over their lives, and a less satisfying quality of life.1

Key Words:
Androgenetic alopecia, Antiandrogens, Minoxidil, Reductase Inhibitors, Transplantation

Female androgenetic alopecia is a common and perplexing clinical problem. Although there are no reliable data, Professor Constantin Orfanos of Berlin feels that 20-40% of European women have androgenetic hair loss to some extent.2 Earliest onset is at puberty, while later onset occurs in the second to fourth decade of life. The most common pattern of hair loss is the diffuse parietal thinning of scalp hair with retention of the frontal hairline.3 Most affected women do not have elevated levels of circulating androgens, and they have normal menses, normal pregnancies, and are not virilized.4

Pathophysiology

Androgen processing in hair follicles appears to be different in males and females even though scalp follicles demonstrate similar metabolic pathways.3 Although young females have twice as much 5-α reductase in frontal hair follicles than in occipital hair follicles, levels in the former are still only half those found in young males. Aromatase converts testosterone to estradiol in both males and females, but young females have higher levels of aromatase in scalp hair follicles than their male counterparts. These differences are thought to explain the milder form of androgenetic alopecia and the sparing of the frontal hairline seen in females.5

Clinical Evaluation

Hair braiding, hot combing, chronic illness, crash dieting6 and nutritional alterations, metabolic and endocrine disorders, stress, environmental changes, surgical procedures, and certain drugs can precipitate or exacerbate alopecia.3 Patients should be asked about their use of exogenous estrogens, progesterones, anabolic steroids, and testosterone.

Hyperandrogenism might be suspected if the androgenetic alopecia is of rapid onset (months to one year), there is significant fronto-parietal recession, or there is no strongly positive family history.7 The most common androgen excess syndromes resulting in alopecia are lateonset adrenal hyperplasia, polycystic ovarian disease, and relative estrogen depletion in the perimenopausal female.3

In practice, one only needs to measure testosterone, DHEAS, and prolactin levels if there are menstrual irregularities or infertility, or signs of hirsutism, cystic acne, galactorrhea, or virilization.5 If none of these signs are present, no hormonal tests are required but if there is significant hair thinning and other causes need to be eliminated, test TSH.5

Treatment

Treatment of female androgenetic alopecia varies from country to country, depending on local preferences and experience, as well as on the availability of some drugs.

Antiandrogens

Cyproterone acetate (not available in the USA). In Europe, cyproterone is the major drug used for the treatment of androgenetic hair loss in women.8 Professor Orfanos’ preferred treatment is cyproterone acetate 2 mg (together with ethinylestradiol 50 mcg in Diane® or 10-20mg (Androcur®), plus topical application of estrogen containing hair lotions such as Crinohermal®. However, the efficacy of estrogen containing hair lotions remains unproven, and they are not approved for use in many countries, including North America. In Canada, 50-100 mg of Androcur® are given daily from days 5-14 of the menstrual cycle, while doses of 10-20 mg per day are used for acne but not for alopecia androgenetica in females.9

Spironolactone. In cases where there is androgen excess, spironolactone (Aldactone®) has been effective in doses of 75-200 mg per day.3 Most of the studies have been uncontrolled and conducted in small numbers of patients. Nonetheless, extrapolating data from hirsutism trials, it does appear that a dose of at least 100 mg a day is necessary for efficacy in androgen-mediated hair disorders.

Minoxidil

Where cyproterone is not approved (as in the USA), minoxidil (Rogaine®) may be the treatment of choice. Studies have shown that minoxidil can reduce the extent of hair loss to a cosmetically acceptable degree,10 and increase hair weight and number11,12 without causing serious or unexpected medical events.12 In countries where cyproterone is available, minoxidil is less important in treating this condition.

5-α Reductase Inhibitors

Several 5-α reductase inhibitors are in clinical development. Finasteride (Procepia®) is being studied in male alopecia and in post-menopausal patients with androgenetic alopecia.5,9

Hair Transplantation

In the past, hair transplantation was not widely used because female patients with androgenetic alopecia often have fine, thin hair all over the scalp, and hair loss is not as well demarcated as in men. However, advances in technique have allowed many women, previously thought to be ineligible for surgery, to benefit from this procedure.13 The mini- or micrograft technique is useful in women who have very profound thinning in the front of the scalp and have a good density of thick hair in the occiput. Attaining a natural-looking result in female patients is easier because the frontal hairline is usually still present.14 Expectations must be realistic, and the surgeon must explain carefully what can and cannot be achieved.13

Approaches for Patients Unsuitable for Medical or Surgical Treatment

Suggestions kindly provided by Dr. Zoe Draelos, Department of Dermatology, Bowman Gray School of Medicine, Wake Forest University, North Carolina

Scalp Camouflage15

The contrast between a pale bald scalp and dark hair often accentuates hair loss. The contrast can be minimized by colouring the scalp temporarily with wax crayons or vegetable dyes, or permanently with tattoo pigment.

Cosmetic Hair Techniques 15

Styling should add volume and fullness. Setting tight curls yields more hair fullness; back-combing or teasing can allow the hair to stand away from the scalp creating the illusion of volume. It is important to avoid hair breakage in areas where the hair is already thinned. Styling products such as gels, mousses, and hair sprays also help the hair to stand away from the scalp but lose their hold each time the hair is wetted or combed and need to be reapplied each time the hair is restyled. Permanent hair waving also increases apparent hair volume; but to minimize damage to the hair shaft, this must be performed with care and with as much time as possible between repeats.15

Crepe hair can camouflage very small, localized areas of scalp in patients who need an inexpensive, short-term camouflage. Hair pieces can provide extra hair in the frontoparietal region. Hair additions can also be useful to camouflage frontoparietal thinning, but the styling time required can be expensive and the extra weight of the added hair can cause traction alopecia.15

Permanent dyes can be used to lighten hair colour to blend in better with the pale scalp, but permanent hair dyes are damaging to the hair shaft.15

Future

Future breakthroughs in the treatment of female androgenetic alopecia may come from application of molecular biology developments to growth factors and to blocking specific receptors with cytokines or antisense oligonucleotides.5

References

  1. Cash TF, Price VH, Savin RC. Psychological effects of androgenetic alopecia on women: comparisons with balding men and with female control subjects. J Am Acad Dermatol 1993;29: 568-575.
  2. Orfanos C. Personal communication. June 1996.
  3. Bergfeld WF, Redmond GP. Androgenic alopecia. Dermatol Clin 1987; 5: 491-500.
  4. Price VH. Androgenetic alopecia and hair growth promotion state of the art: present and future. Clin Dermatol 1988; 6: 218-227.
  5. Price VH. Androgenetic alopecia. Clinical Dermatology 2000. Vancouver, Canada, May 1996.
  6. Goette DK, Odom RB. Alopecia in crash dieters. JAMA 1976; 235: 2622-2623.
  7. Callan AW, Montalto J. Female androgenetic alopecia: an update. Australas J Dermatol 1995; 36: 51-57.
  8. Happle R. Personal communication. June 1996.
  9. Shapiro J. Personal communication. September 1996.
  10. Hordinsky MK, Shank J. 3% topical minoxidil therapy for female androgenetic alopecia. Clin Dermatol 1988; 6:213-217.
  11. Price VH, Menefee E. Quantitative estimation of hair growth 1. Androgenetic alopecia in women: effect of minoxidil. J Invest Dermatol 1990; 95: 683-687.
  12. DeVillez RL, Jacobs JP, Szpunar CA, et al. Androgenetic alopecia in the female. Treatment with 2% topical minoxidil solution. Arch Dermatol 1994; 130: 303-307.
  13. Cotterill PC. Hair transplantation in females. In: Unger WP, ed. Hair transplantation. New York: Marcel Dekker, 1995: 287-292.
  14. Rivers J. Personal communication. November 1996.
  15. Draelos ZD, ed. Cosmetics in dermatology. Second edition. New York: Churchill Livingstone, 1995: 186-188.