hair

Female Androgenetic Alopecia

Generality

Alopecia, or localized or widespread hair loss, is a phenomenon that affects large sections of the population, both male and female.

In the most common and widespread form, hair loss is related to the action of androgenic hormones on a genetically predisposed soil; therefore we talk about androgenetic alopecia.

According to recent estimates, this condition affects 18 million Italians and 4 million Italians, so much so that at the age of 50 at least half of men and 30% of women suffer from more or less serious problems of baldness related to alopecia androgenetic.

In women, hair loss, although generally more subdued than in men, often leads to far more dramatic and devastating psychological repercussions, linked to the perception of considerable damage to one's image. Fortunately, the treatment of female androgenetic alopecia offers more and more effective therapeutic opportunities, with a lower incidence of side effects.

Causes

An essential element in all forms of androgenetic alopecia is - as the name suggests - the presence of androgens. In fact, in the absence of these hormones - as seen in early castrated males - baldness does not occur.

However, in the article on the relationship between androgens and hair we explained how hormone levels are quite similar in bald men compared to the general population. Male androgenetic alopecia, therefore, is not generally related to excess androgens, but rather to the excessive sensitivity of the hair follicles to their action. In fact, since birth some hairs are genetically predisposed to receive the "miniaturizing" stimulus of androgens. It is no coincidence that androgenetic alopecia is a slow phenomenon which - by increasingly shortening the growth phases and lengthening the resting phases preceding the fall - involves the gradual transformation of the terminal hair into goblin hair (thin, depigmented, very short and almost imperceptible). ).

As explained above, women suffering from hyperandrogenism (excess of androgens) are clearly more susceptible to alopecia, even if the two conditions are not always and necessarily correlated. Women suffering from acne, seborrhea, hypertrichosis and hirsutism (suggestive but not pathognomic signs of hyperandrogenism), are therefore more likely to suffer from female alopecia.

In women, most cases of hyperandrogenism are attributable to polycystic ovary syndrome (PCOS), which at clinical level is manifested by anovulatory cycles, menstrual changes, hirsutism and sometimes obesity. This latter condition is often correlated, either as a consequence or as a trigger, to states of hyperandrogenism, probably favored by the variable degree of insulin resistance associated with it. The cases of hyperandrogenism linked to the presence of androgenic secreting neoplasms are rarer.

Also the levels of estrogens, hormones that unlike androgens are typical of women, particularly during fertile age, influence - this time positively - the health of the hair.

Furthermore, at the level of the hair and hair bulbs, there may be variable concentrations of enzymes acting on androgens and estrogens, which transform them into derivatives capable of influencing the life of the hair to a much greater extent. The best known of these enzymes is called 5-alpha-reductase and acts on testosterone transforming it into dihydrotestosterone, the real cause of hair involution and subsequent thinning.

The aromatase enzyme, on the other hand, converts androgens into estrogens, prolonging the life of the hair and counteracting baldness; a similar action is also performed by the 3-alpha-steroid dehydrogenase and 17-beta-hydroxysteroid dehydrogenase enzymes. For this reason, female androgenetic alopecia can be noticed for the first time, or become more evident, after menopause, a period in which a generalized decrease in estrogens is observed with variation in the percentage ratio between ovarian and adrenal steroids. Subject to the always necessary genetic predisposition, the same circumstance can therefore manifest itself in coincidence of hormonal changes, due, for example, to a birth or the beginning or the interruption of estro-progestinic treatments (including those for contraceptive purpose.

Symptoms and Features

The hereditary component is another distinctive feature of androgenetic alopecia; consequently, it is much more likely to blame the problem when it has already become evident in parents, grandparents, uncles or brothers.

Female androgenetic alopecia is distinguished from the male one by a later appearance of thinning, which is generally noted for the first time between the ages of 30 and 40, and due to its different localization. In fact, while in men the problems of baldness affect the fronto-occipital area, in the woman they involve a more diffused region, in particular the vertex or in any case the areas behind the fronto-temporal line. Another distinctive trait is the greater gradualness with which female alopecia manifests itself with respect to what happens in men.

Clinically, the androgenetic alopecia of the woman often manifests itself progressively passing for three phases of increasing gravity, illustrated in the figure (Ludwig's Scale, 1977). The thinning therefore affects the vertex area and to a lesser extent the parietal areas, always saving a frontal band of hair. Moreover, unlike the male, the areas most affected by alopecia always retain a not inconsiderable number of terminal hair (miniaturized).

Diagnosis

In women, the precociousness of diagnosis and therapeutic intervention is very important to stop the process of involution of the follicles, making the hair regain its original splendor before the problem becomes irreversible.

The key examination for the diagnosis of female alopecia is the trichogram, naturally alongside the inevitable medical history and the evaluation of the clinical picture.

The familiarity of alopecia, the intake of contraceptive pills or cortisonics, the possible use of anabolic steroids and the regularity of the menstrual cycle will be evaluated in particular, searching for possible signs of hyperandrogenism (lowering of the voice, diffused hair in typically male areas, obesity, acne, etc.).

To confirm or exclude what emerges from the anamnestic data and the physical examination, it is necessary to proceed to endocrinological laboratory tests, during which the blood concentrations of androgens, cortisol, thyroid hormones, TSH, SHBG, estrogens, progesterone and gonadotropins (LH, FSH), also in relation to the various phases of the menstrual cycle.

Only in this way it will be possible to intervene pharmacologically on the delicate hormonal balance of the woman, improving the therapeutic efficacy of the treatment and minimizing the side effects.

Treatment

The pharmacological treatment options for female androgenetic alopecia, largely impractical in humans, must first be distinguished into topical and systemic.

The first group includes drugs to be applied directly to the scalp, such as the famous minoxidil or estrone sulfate . The topical administration of hydroalcoholic solutions of natural progesterone or its 17-hydroxylated derivatives, whether or not associated with spironolactone, also appears effective in this sense. There is also the possibility of counteracting the activity of the 5-alpha-reductase enzyme by topical application of azelaic acid .

The systemic pharmacological therapy of female androgenetic alopecia is indicated before cases of dysfunctional hyperandrogenism, as in the case of PCOS; while in hyperandrogenisms sustained by organic causes (for example, by androgen-secreting neoplasms) it is necessary to remove the cause by surgical intervention.

These drugs include spironolactone which - to limit the side effects associated with therapy (amenorrhea, mastodynia, chloasma) - must be taken systemically from the 16th to the 25th day of the cycle, better if combined with an estroprogestinico to guarantee contraception .

In the case of progestin deficiency, on the other hand, the administration of synthesis progestogens by systemic route is indicated.

However, the most commonly adopted therapeutic solution remains the combined administration of estrogens and progestins, in particular of ethinylestradiol and cyproterone acetate (endowed with important antiandrogenic activities). This therapeutic intervention is exploited not only in the treatment of female androgenetic alopecia, but also in the treatment of the manifestations of hyperandrogenism in women.

To learn more: Drugs for the Treatment of Female Androgenetic Alopecia »