Clinical Characteristics and Factors Associated With Different BASP Subtypes of Androgenetic Alopecia

This study investigated factors associated with different BASP subtypes of androgenetic alopecia (AGA) in 1,505 patients and 1,751 healthy controls. Key factors independently linked to AGA included male sex, older age, smoking, parental hair loss history, higher BMI, shorter shampooing intervals, scalp oiliness, high-fat diet, heart disease, hyperlipidemia, fatty liver, lower serum 25-hydroxyvitamin D levels, and higher homocysteine levels. Severity of BASP subtypes was consistently associated with age, father's hair loss history, high-fat diet, lower vitamin D, and higher homocysteine, with additional subtype-specific factors such as male sex, drinking, hypertension, diabetes, and fatty liver. These findings highlight the importance of demographic, familial, lifestyle, and metabolic factors in AGA, though further prospective studies are needed for causal interpretation.