Hormonal hereditary hair loss (alopecia androgenetica)

Hormonal hereditary hair loss (alopecia androgenetica) is the most common cause of hair loss. Alopecia androgenetica is responsible for hair loss in about 95 percent of cases. This is caused by a genetically determined hypersensitivity of the hair roots to testosterone (male sex hormone), which leads to premature loss of the hair on the head.

Alopecia androgenetica primarily affects men from the age of 20 to 25. In some cases, hair loss begins earlier. About 50 percent of all men suffer from hormone-induced hair loss in the course of their lives.

Women can also be affected by alopecia androgenetica - however, due to the lower production of testosterone in the body, this is much less common than in men. Before the onset of menopause (menopause), an estimated ten percent of all women suffer from hormonal hereditary hair loss, and in the post-menopausal phase of life, about 25 percent.

Contrary to the widespread opinion that hormonal hereditary hair loss is due to an excessive production of the male sex hormone testosterone, the cause lies in an inherited hypersensitivity of the hair roots to androgens (male hormones). The view that bald men are particularly potent due to high testosterone levels is therefore proven to be false.

If there is a genetically-conditioned hypersensitivity to androgens (e.g. testosterone), the growth phase of the hair becomes shorter and shorter under the influence of androgens. In addition, the hair follicles shrink visibly. This leads to the fact that with time only thin and hardly visible vellus hairs (wool hairs) can be formed. The vellus hairs remain on the scalp or fall out completely without the formation of new hair.

Menopause plays a major role in genetic hair loss in women. The change in hormone balance during menopause promotes hair loss.

The course of hair loss differs in men and women:

Men

For every man with hormonal hereditary hair loss, there are slight differences in the course of hair loss. Hair loss may be limited to clearly defined bald patches - in other affected individuals, a fuzz of woolly hairs (vellus hairs) on the top of the head persists into old age.

Frequently, hair loss begins above the temples, resulting in the formation of so-called receding hairline. As the condition progresses, the hair on the top of the head also becomes thinner until there is only a crown of hair at the back or sides, which is known as a bald forehead. In some affected individuals, a complete loss of the main hair sets in, resulting in a full bald head.

In many cases, hormone-induced hair loss becomes noticeable in men between the ages of 20 and 25 - sometimes hair loss starts earlier.

Women

Hormone-related hair loss in women is different from that in men. The hair often thins out along the crown of the head, but complete baldness is rare. The reason for this is that, unlike male sufferers, not all the hair follicles of the head are affected by the hypersensitivity to androgens, which means that some of the hair remains.

Women can already suffer from alopecia androgenetica before menopause - typically, however, the genetic hair loss only becomes noticeable after menopause.

By means of a physical examination by the doctor, it can be determined whether hair loss is present. Alopecia androgenetica (hereditary hair loss) can be clearly diagnosed by the characteristic picture of hair thinning and balding.

The creation of a trichogram can be helpful in determining the exact type of hair loss. In the process, approximately 20 to 50 hairs are epilated (plucked out) using a clamp, which are then examined under the microscope. By assessing the hair roots, conclusions can be drawn about the growth behaviour of the scalp hair, which allows the extent of the hair loss to be estimated.

There are various treatment approaches available for the treatment of alopecia androgenetica:

Hair Transplantation

One way of preserving the hair on the head is hair transplantation. Thanks to the fact that the hair follicles at the back of the head are usually not hypersensitive to testosterone, tiny pieces of tissue from the back of the head can be transplanted onto the hairless areas of skin. In this way, complete head hair can be restored. However, the result does not look as natural as it can be achieved by successful drug therapy, which prevents the original hair from falling out. Alternatively, artificial hair can be applied to the bald areas of the scalp.

Drug therapy

With the help of medication against alopecia androgenetica, the actual condition of the scalp hair can be maintained or even a thickening of the hair can be achieved. However, the effect only lasts as long as the corresponding preparations are taken - as soon as the medication is discontinued, the hair loss usually progresses again. In some patients, however, the preparations have no effect.

For a good treatment result, the therapy should be started as early as possible. At the beginning, hair tinctures are often used, which are applied locally to the affected areas, since this way the body is least stressed. After about three to six months, if the treatment is successful, there is an improvement in hair loss. If the scalp hair does not respond to topical treatment, tablet therapy may also be considered.

Most of the available preparations against hair loss require a prescription. There are different active ingredient recommendations for men and women:

Medications for male sufferers

Finasteride , which prevents the conversion of testosterone to dihydrotestosterone (the active form of testosterone), is often used. Finasteride can be used to prevent the progression of hormone-induced hair loss in about 90 percent of patients, and to thicken the hair on the head in about 50 percent of cases.

As a possible side effect, finasteride can cause an impairment of libido (sexual desire) and potency. Small amounts of the active ingredient have also been detected in seminal fluid during use. Finasteride use in women during pregnancy carries a risk of causing birth defects in the unborn child.

Medication for female patients

If women want to use the pill for contraception, it is advisable to use preparations in which oestrogens and special progestogens are combined. The anti-androgenic effect (inhibition of the testosterone effect) of the gestagens can treat the hereditary hair loss. Combinations of the active substances dienogest and ethinylestradiol, chlormadinone and ethinylestradiol or mestranol show very good results. Very severe forms of hair loss are treated with cyproterone with ethinylestradiol.

For the treatment of hereditary hair loss after menopause, dienogest, chlormadinone or cyproterone can be used as single preparations.

Medications for women and men

The estrogen 17-alpha-estradiol is available over the counter and is used as a hair tincture. Similar to finasteride, 17-alpha-estradiol prevents the conversion of testosterone into its active form. The product is applied to the scalp once daily.

The active ingredient minoxidil is also used in the form of a hair tincture. It promotes blood flow to the hair follicles and is thus said to stimulate hair growth. Minoxidil is applied twice a day.

The prognosis of alopecia androgenetica (hormonal hereditary hair loss) varies greatly from person to person. Depending on the individual predisposition, treatment can be successful or the affected persons respond little or not at all to the therapy.

At the earliest, six months after the start of therapy, it is possible to assess whether patients are responding to treatment. Even if the therapy is successful, hair loss starts again as soon as the respective preparations are discontinued.