Prevalence of androgenetic alopecia in China: a community-based study in six cities

P>Background There are racial differences in the prevalence and types of androgenetic alopecia (AGA). The prevalence of AGA has been studied in Caucasians and in some Asian people. In China, although there have been some epidemiological studies carried out in single cities or regions, no multicentre population-based study has been reported. Objectives To study the prevalence and types of AGA in China and to compare the results with those previously reported in Caucasians and in other Asian people. Methods A community-based study was carried out in six cities of China. Subjects were interviewed face-to-face and completed questionnaires. The degree of AGA was classified according to the Norwood and Ludwig classifications. Results In total 17 886 subjects were interviewed and 15 257 completed the questionnaires. In men, the overall prevalence of AGA was 21 center dot 3%, with 2 center dot 8% in men aged 18-29 years, 13 center dot 3% in those aged 30-39 years, 21 center dot 4% in those aged 40-49 years, 31 center dot 9% in those aged 50-59 years, 36 center dot 2% in those aged 60-69 years and 41 center dot 4% in those aged 70 years and over. The most common type was frontal and vertex hair loss. A small number of subjects (3 center dot 7%) showed 'female pattern' hair loss. In women, the prevalence of AGA was 6 center dot 0%, with 1 center dot 3% in women aged 18-29 years, 2 center dot 3% in those aged 30-39 years, 5 center dot 4% in those aged 40-49 years, 7 center dot 5% in those aged 50-59 years, 10 center dot 3% in those aged 60-69 years and 11 center dot 8% in those aged 70 years and over. Ludwig grade I was the most common type. The prevalence of AGA varied between cities. A positive family history was present in 29 center dot 7% of men and 19 center dot 2% of women with AGA. Conclusions The prevalence of AGA in Chinese men and women was lower than in Caucasians and similar to that in Koreans.