Dados do Trabalho

Título

The role of the pro-inflammatory cytokine IL-17A in insomnia in a sample of individuals with vitiligo

Introdução

The role of IL-17A in insomnia has been minimally explored, especially in individuals with the autoimmune skin disorder vitiligo. This skin disease has a great impact in the quality of life and sleep of the patient, in which insomnia should be investigated. The IL-17A is a pro-inflammatory cytokine, and it has a somnogenic role, which becomes a subject of interest in respect of sleep disorders. Vitiligo and sleep disturbance can have a bidirectional immune pathway, with relevant participation of the immune cytokines with circadian influence, such as IL-17A; and the expression of T helper (Th) responses, particularly Th17 in autoimmune diseases.

Objetivo

The aim of this study was to investigate the role of IL-17A in a sample of vitiligo compared with controls, and associate its levels with the occurrence of insomnia in these individuals.

Métodos

The serum levels of IL-17A were analyzed using a plex kit in 30 patients diagnosed with vitiligo and compared with those in 26 healthy controls. All these individuals accessed the Insomnia Severity Index (ISI) to estimate the occurrence of clinical insomnia. Statistical analysis was performed by the Generalized Linear Model.

Resultados

The serum levels of IL-17A did not differ between groups (vitiligo mean: 3.24; control mean: 3.33; p=0.96). The ISI total score was 9.55 in the vitiligo group (suggesting subthreshold insomnia), and 6.87 in the control group (indicating the absence of clinically relevant insomnia). When the cytokine levels between groups were analyzed with ISI scores, each unitary elevation of IL-17A was related to the increase of ISI score and worse insomnia symptoms.

Conclusões

Although the IL-17A levels were not different between groups, when related to the ISI scores, the increase of this cytokine was associated with worse insomnia in this sample. There is a lack in the literature regarding the relationship of this cytokine with insomnia. As a pro-inflammatory cytokine, there is evidence that the higher IL-17A levels can be related with vitiligo activity and worsening of this skin disease. Regarding sleep, some studies have found that higher levels of IL-17A can be linked to sleep disturbances, and sleep disorders, including the severity of obstructive sleep apnea (OSA). The Th17 immune response and IL-17A levels have an important role in the immunological and inflammatory regulation and should be increasingly explored regarding vitiligo and sleep.
Funding: CAPES, CNPq and AFIP.

Palavras -chave

Sleep, vitiligo, immunology, cytokines, IL-17A.