Title : Relationship between androgenetic alopecia and body composition: A preliminary report

Background: Androgenetic alopecia (AGA) is the most prevalent form of hair loss in men. Accumulating evidence suggests that AGA may not be solely a cosmetic condition but may be associated with systemic conditions including metabolic syndrome and chronic low-grade inflammation. This preliminary study was designed as a methodological foundation for a more comprehensive investigation.

Objective: To evaluate the relationship between AGA and body composition parameters — specifically BMI, waist circumference, and metabolic age — and to provide the methodological and conceptual basis for the main study.

Methods: A total of 49 male subjects were stratified into AGA and control groups according to the Hamilton–Norwood scale. BMI, waist circumference, and metabolic age were measured using a Tanita bioelectrical impedance analyzer. Statistical analyses included Student's t-test, multiple linear regression, Random Forest, Support Vector Machine (SVM), and clustering analyses. This study was conducted under Ethics Committee Approval No: TABED 1-26-2112.

Results: Waist circumference was significantly elevated in the AGA group compared to controls (88.4 vs 81.2 cm; p = 0.047). BMI (25.7 vs 23.9) and metabolic age (23.2 vs 21.6) were also higher in the AGA group, though the difference in metabolic age did not reach statistical significance (p = 0.066). Multiple regression incorporating age, metabolic age, and waist circumference demonstrated a strong combined effect on BMI (R² = 0.935). Machine learning classifiers yielded 78.4% accuracy (Random Forest) and 65.3% accuracy (SVM). Cluster analysis produced a silhouette score of 0.617, indicating moderate cluster separation.

Conclusions: These findings support the hypothesis that AGA is associated with systemic metabolic alterations, particularly central adiposity. This preliminary report has informed the design and hypotheses of the main study titled "Evaluation of the Relationship Between Hamilton–Norwood Scoring and Segmental Body Composition Analysis, Metabolic Syndrome, and Systemic Inflammation Parameters in Male Patients with Androgenetic Alopecia," which is currently underway with a larger cohort.

Table 1. Body Composition Parameters by Group

* p < 0.05; BMI: Body Mass Index

Dr. Alperen Kızılkaya was born in 1998 in Erzurum, Turkey. He completed his secondary education at İzmir Atatürk High School and received his medical degree from Dokuz Eylül University Faculty of Medicine. He is currently in the final year of his dermatology residency at Ankara Bilkent City Hospital, working under the supervision of Prof. Dr. Akın Aktaş. His research interests include aesthetics, androgenetic alopecia, dermatosurgery, inflammation, and metabolism.