**4.1 Alopecia and depression**

The presence of depressive symptoms in alopecia areata patients has been known for years. Colon et al. in their study, they predicted the lifetime prevalence of major depressive disorder as 39% in patients with alopecia areata [55]. Studies on this subject in the following years also suggest that the incidence of depression in alopecia has increased. Şahin et al., in their study with the beck depression inventory, compared the patients followed up with the diagnosis of alopecia areata and healthy volunteers; found the rate of depression to be 16.7% in healthy volunteers and 64.6% in patients with alopecia [56]. In the study of Arı et al., in which they compared the Beck depression, beck anxiety and alexithymia scale with patients with alopecia and healthy volunteers, no difference was found between the groups in terms of anxiety and alexithymia, but the depression scores of the alopecia group were found to be higher [57]. In another study conducted with the hospital anxiety depression scale, depression was found to be significantly higher than the control group with 38% [58]. The limitation of all these studies is that they are based on the use of scales rather than clinical interviews, but on the other hand, there seems to be an accumulation of knowledge that depressive symptoms are more common in patients with alopecia. It appears to be a risk group for major depressive disorder in children and adolescents with alopecia. In a study conducted with the evaluation of 5117 patients with alopecia areata in Taiwan, it was determined that alopecia areata, which started under the age of 20, poses a risk for major depressive disorder [24]. Although depression is thought to be more common in patients with alopecia, another point of view is the possibility that depression may exacerbate alopecia. In a case-control study conducted in Taiwan, patients with alopecia areata had higher rates of psychiatric disease; however, 50% of these people have been shown to have a psychiatric illness that precedes alopecia [24]. It has also been reported that a quarter of patients with alopecia areata experience stressful life events before the onset or exacerbation of the disease [59]. In another study, a significant relationship was shown between exacerbations in patients with alopecia areata and the patients' perception of stress and state anxiety scores [60]. Studies have shown that imipramine, an antidepressant drug, and hypnotic approaches reduce depressive symptoms in alopecia areata and produce significant hair growth [61, 62]. There are other studies showing that the onset and exacerbations of alopecia areata may be associated with stressful life events. In fact, it is known that the stress response of the hypothalamopituitary axis (HPA) in the face of emotional stress can trigger not only alopecia, but also many other dermatological diseases (psoriasis, atopic dermatitis, urticaria, vitiligo, acne, etc.). There are studies that associate and investigate this link with common neuromediators associated with psychoneuroimmunological systems [63].

## **4.2 Alopecia and anxiety disorders**

Many studies have shown that anxiety disorders are more common in alopecia areata. It is now accepted that visual lesions in the hair can have negative psychological consequences. In addition to the physical appearance of the disease, it has been shown that the chronic and poor course also causes anxiety. This can

cause great concern, especially in women and young adults [62, 64]. In one study, generalized anxiety disorder was found in 39% of patients with alopecia areata. The same study reported that the frequency of anxiety disorders is higher in first-degree relatives of patients with alopecia [55]. Later, many studies have been conducted to support the knowledge that anxiety disorders are common in alopecia areata [17]. Onset at different ages in alopecia areta can also be a risk factor. Onset between the ages of 20 and 39 has been shown to be a risk factor for anxiety disorders [24]. In a study conducted in patients with refractory alopecia areata, hypnosis was used to improve psychiatric symptoms; It was determined that the severity of alopecia of the patients whose psychiatric symptoms improved, also decreased [62]. The most common anxiety disorder with alopecia areata is obsessive compulsive disorder [28].
