Crowning hair loss in women linked to male hormone

The scalp has an average of 100,000 hairs. More than 90 percent of these hairs are actively growing. Normally, hair loss happens at the rate of about 100 hairs per day. It is found that more than one third of women experience clinically significant hair loss during their lifetime.

In a case article featured in The New England Journal of Medicine, submitted by Dr. Jerry Shapiro from the Department of Dermatology and Skin Science, University of British Columbia, a middle-aged woman had thinning hair wide on top of the scalp for over a year. She is a vegetarian and her father was bald.

Causes of hair loss

The author reported that the most common cause of nonscarring hair loss in women is androgenetic alopecia, a female-pattern hair loss that is related to the male hormone androgen. The pattern is often characterized by thinning at the crown of the head but sparing the hairline and the scalp at the back of the head. Androgenic alopecia (baldness) in men involves the hairline and the crown, leaving out only the hair around the sides and the rear of the head. Androgenic alopecia is familial.

Hair loss is a common symptom among diseases that involve the entire body. Alopecia that begins three months after a major illness, surgery, nutritional deficiency, hormonal dysfunction and other stresses is called telogen effluvium (named after the telogen growth phase of the hair that follows after a period of hair loss). Telogen effluvium lasts for up to six months after the trigger has stopped.

Anagen effluvium, on the other hand, is hair loss associated with chemotherapy, which causes immediate destruction and release of anagen hair (mature hair that lasts for three to seven years before falling out).

A less common cause of baldness is alopecia areata. It usually appears as random patches of hair loss around the scalp. Although reversible, it can recur and may progress to total baldness (may include body hair).

Hair care practices that can cause fragility or brittle hair, such as perming, bleaching, hair relaxing, braiding and compulsive hair pulling, can trigger hair loss.

Severe bacterial or fungal infections and iron deficiency are also associated with hair loss. A strict vegetarian diet can result in low levels of iron in the body.

Treatment

Minoxidil solution. A topical 2% minoxidil solution is an FDA-approved preparation for women with thinning hair due to female-pattern baldness (androgenic alopecia). It is found to affect minimal hair regrowth in 50 percent of women and moderate regrowth in 13 percent of women after 32 weeks of application. Improvement can be seen after six to 12 months of treatment.

Antiandrogen therapy. Antiandrogen agents (such as spironolactone, cyproterone acetate, flutamide and finasteride) and oral contraceptives are not FDA-approved for the treatment of androgenic alopecia, but they are commonly used in Europe. Although finasteride is not approved as treatment for women, it is approved for the treatment of hair loss in men.

Hair transplantation. Grafts or strips of scalp skin bearing two to three hair follicles planted on bald areas of the scalp have been found to achieve natural and cosmetically acceptable results for female-pattern hair loss.

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