The familial risk of acne vulgaris in Chinese Hans - a case-control study

Background Acne is a chronic inflammatory disease of the pilosebaceous follicles. Recent studies bring us increasing evidences that hereditary factors play an important but indirect role in acne. Objective To investigate the possible role of genetic factors in the pathogenesis of acne vulgaris in Chinese Han ethnic group. Patients and methods Volunteers of 975 acne cases and 580 controls were included, contributing 3009 and 1825 first-degree relatives, respectively. One thousand and eighty-five first-degree relatives of acne cases were affected with facial acne. This compared with 223 first-degree relatives of non-acne controls. The odds ratio was used to estimate the relative risk for acne vulgaris associated with having an affected first-degree relative. Results The risk of acne vulgaris occurring in a relative of a patient with acne vulgaris was significantly greater than for the relative of an unaffected individual (odds ratio 4.05, 95% confidence interval (CI): 3.45-4.76, P < 0.001). Conclusion Our study suggests that familial factors are important in determining individual susceptibility to acne vulgaris.