Circulating and/or cutaneous irisin resistance: A novel link among androgenetic alopecia, comorbid metabolic syndrome and cardiovascular risks

Abstract

Background: Androgenetic alopecia (AGA) is a common cause of hair loss in both genders that may be associated with disturbed systemic metabolism. Irisin is a hormone-like myokine that greatly influences systemic metabolism and is linked to cardiovascular diseases. Aim: To detect irisin role in AGA and its associated metabolic syndrome (MetS) and cardiovascular risk. Patients/Methods: This case–control study included 44 AGA patients of both genders and 22 healthy individuals. Serum irisin level was measured using ELISA and scalp biopsy was taken to detect irisin immunohistochemically. Carotid Doppler ultrasonography was performed to measure carotid intima media thickness (CIMT). Results: Higher serum irisin was significantly detected in AGA patients (p ˂ 0.001), and in males (p = 0.01) particularly severe cases (p ˂ 0.001). It was significantly higher in AGA patients presenting with MetS and those suffering from dyslipidemia (p ˂ 0.001 for both). Multivariate regression analysis proved BMI (p = 0.01) and serum irisin (p = 0.02) as independent predictors of CIMT abnormality among AGA patients. Regarding cutaneous irisin expression, the epidermal H-score was significantly higher in AGA patients with MetS compared to those without (p = 0.04). Epidermal H-score ˃100 was significantly associated with male gender (p = 0.05), severe AGA (p = 0.02), MetS (p = 0.03), dyslipidemia (p = 0.03), and abnormal CIMT (p = 0.03). Conclusion: High serum irisin and upregulated epidermal irisin expression are associated with the incidence of MetS, dyslipidemia, and CIMT abnormality among AGA patients. This may indicate resistance to irisin, which hinders its favorable cardiometabolic actions. Further studies are warranted to investigate the concept of irisin resistance in AGA patients, which was uniquely discussed in the present study.