Gender-specific association of androgenetic alopecia with metabolic syndrome in a middle-aged Korean population

Background Although several previous studies have investigated the association between metabolic syndrome (MetS) and androgenetic alopecia (AGA), the study results have been inconsistent. Objectives The aim of this study was to investigate the relationship between the presence of MetS and AGA according to gender in a middle-aged Korean population. Methods A population-based cross-sectional study was conducted on a sample from the Korean Genome Epidemiology Study. In total, 3408 subjects (1707 men and 1701 women) were enrolled between January 2008 and February 2010. The Norwood classification for men and Ludwig classification for women were used for assessment of the degree of hair loss. Information on components of MetS together with other possible risk factors was collected. Results In men, the risk of having Norwood type IV or greater was not increased for subjects with MetS compared with those without MetS. In women, the risk of having Ludwig type I or greater was significantly increased for subjects with MetS compared with those without MetS after controlling for age and smoking status (OR 1·68, 95% CI 1·14-2·48; P = 0·01). Similar results were also observed for the number of fulfilled components of MetS [odds ratio (OR) 1·38, 95% confidence interval (CI) 1·00-1·91; P < 0·05]. When each component of MetS was considered individually, associations between AGA and all five components of MetS (waist circumference, triglycerides, high-density lipoprotein-C, blood glucose, and blood pressure) were not statistically significant. When multiple regression was used to adjust for age, family history and smoking, there was no significant association between the prevalence of MetS and moderate to severe AGA in the male group. On the contrary, a statistically significant positive association was noted between the prevalence of MetS and AGA in the female group. Conclusions Our analysis of AGA and the prevalence of MetS in a large population-based cohort demonstrated quite different findings compared with previous reports. The different results according to gender suggest that there may be different mechanisms that are yet to be defined between male and female AGA.