Background:Halo nevus (HN) has been shown to be associated with vitiligo,but no standard signs are currently available to identify HN patients at risk of vitiligo,and the relevant data obtained in previous studies are somewhat conflicting.This study aimed to identify factors affecting the presence of vitiligo in HN patients.Methods:We performed a retrospective study on consecutive patients with HN at the First Affiliated Hospital of Sun Yat-sen University between January 2011 and December 2016.Detailed demographic and clinical data were collected to identify the factors associated with the presence of vitiligo in this cohort of patients using uni-and multi-variate logistic regression analyses.Results:A total of 212 HN patients were included,101 of whom had vitiligo-associated HN (HNV).Univariate analysis indicated that a personal history of thyroid diseases was positively associated with HNV (odds ratio [OR] =10.761,P =0.025),while the onset age of HN was negatively associated with HNV (OR =0.537,P =0.026).Multivariate analysis demonstrated that the Koebner phenomenon (KP;OR =10.632,P ＜ 0.0001),multiple HN (OR =3.918,P ＜ 0.0001),and a familial history of vitiligo (OR =3.222,P =0.014) were independent factors associated with HNV.Conclusions:HN without vitiligo has clinical features distinct from HN associated with vitiligo.HN patients with KP,multiple lesions,or familial history ofvitiligo are more likely to develop vitiligo and therefore should be monitored for clinical signs of such accompanied conditions.