Hirsutism is an excessive growth of terminal hair of the male type, occurring in about 5–15% of premenopausal women. The main links in the pathogenesis of hirsutism include changes in androgen levels and the ratio of different types of androgens in serum, as well as increased sensitivity of the hair follicle to the action of androgens.

The most common cause of hirsutism is polycystic ovary syndrome (PCOS) — 57.7%. Idiopathic hirsutism accounts for 22.6% of cases. Other causes include late congenital adrenal hyperplasia, hyperprolactinemia and thyroid disorders, and pituitary, ovarian, and adrenal tumors. Hirsutism may also be associated with obesity, insulin resistance, diabetes mellitus, hypertension, infertility, and menstrual disorders [1].

In women with excessive androgen levels (PCOS) or increased sensitivity of androgen receptors (idiopathic hirsutism), there is a transformation of weakly colored pubescent hair into thick and pigmented terminal hair on more extensive areas of the body, such as the lower abdomen, inner thighs, nipples and sternum, above the sacrum, and on the shoulders. Hair growth is also noted on the face: above the upper lip, on the chin, and in the area of sideburns [1].

Laser hair removal is one of the most effective methods of removing unwanted hair. In hirsutism, this method can be referred to as symptomatic therapy aimed at eliminating the manifestations of the disease. In a study by Rafi S. et al., using a diode laser in hirsutism allowed a pronounced cessation of hair growth in the mandibular region, chin, upper lip, and sideburns [2]. According to trichoscopy, the average number of hairs (terminal and vellus) per cm² in the foci of pathologic growth after the 6th hair removal session decreased by 39%, and the number of terminal hairs decreased by 69%. The ratio of terminal and vellus hairs decreased with repeated laser treatment sessions and was statistically significant in all four areas. Thus, after laser hair removal treatment in patients with hirsutism, there was a reduction in the total number of hairs in the foci of pathological growth and a decrease in their thickness — terminal hairs stopped growing or were replaced by vellus hairs.

Despite the pronounced short-term effect of eliminating unwanted hair in hirsutism through laser treatment, it should not be forgotten that pathological hair growth may hide hormonal disorders that can adjust the preservation of the achieved improvements. For this reason, it is necessary to consider the etiology of hirsutism when planning a hair removal treatment.

Nabi N et al. compared the efficacy of epilation in patients with idiopathic hirsutism and hyperandrogenism on the background of PCOS [3]. The duration of the study was 18 months. It included 100 female patients with hirsutism. Group A included 50 patients with idiopathic hirsutism, group B — 50 patients with hirsutism on the background of PCOS. Nd:YAG laser was used for epilation. The epilation treatment included six sessions with an interval of 4 weeks, and the observation period was 3 months. After the 6th laser hair removal session, 70% of patients in group A and 54% in group B had excellent results (hair reduction by more than 75%) compared to baseline. There was a decrease in hair shaft thickness, degree of hair shaft pigmentation, ratio of terminal and vellus hairs, and hair density per cm². Three months after the 6th laser hair removal session, the severity of the results decreased in both groups, but the patients with idiopathic hirsutism maintained the improvements to a greater extent. Thus, unwanted hair in idiopathic hirsutism is better managed by laser hair removal than in the case of hormonally imbalanced PCOS.

Resume

• If there are manifestations of hirsutism, the patient needs a medical examination to clarify the cause of abnormal hair growth.
• In the case of hormonal disorders, laser hair removal should be carried out against the background of the primary treatment aimed at normalizing the level of hormones.
• Unwanted hair in hirsutism is less correctable by laser hair removal, so more hair removal treatments may be required to achieve a pronounced effect.
• It is necessary to form realistic expectations in patients with hirsutism regarding the long-term effects of laser hair removal.

 References

1. Ansari R.T., Syed U., Riaz M., et al. Unveiling the spectrum: A cross-sectional study of hirsutism causes in women. Pak J Med Sci 2024; 40(4): 736–740.
2. Rafi S., Budania A., Bhardwaj A., et al. Efficacy and safety of diode laser for facial hair reduction in hirsutism — a clinico-trichoscopic evaluation. J Cutan Aesthet Surg 2024; 17(1): 19–24.
3. Nabi N., Bhat Y.J., Dar U.K., et al. Comparative study of the clinico-trichoscopic response to treatment of hirsutism with long-pulsed (1064 nm) Nd:YAG laser in idiopathic hirsutism and polycystic ovarian syndrome patients. Lasers Med Sci 2022; 37(1): 545–553.