Recurrence and risk factors in cured patients with vitiligo: A real‐life single‐center retrospective study

The risk of recurrence after successful repigmentation in vitiligo has attracted attention from both patients and clinicians.


| INTRODUC TI ON
Vitiligo is a refractory skin disorder characterized by a progressive loss of melanocytes in the skin and sometimes hair follicles, with a prevalence of 0.5%-2% worldwide. 1,2 Although several treatment modalities have treated the disease efficiently, the recovery remains unsatisfactory because of the high recurrence rate after treatment cessation. However, little is known about the factors that affect the 2 | PATIENTS AND ME THODS

| Patients
This retrospective study was conducted at a single tertiary hospital (Chongqing Hospital of Traditional Chinese Medicine), where patients with vitiligo visited the dermatology clinic were routinely recorded during their every visit. The medical records included patient information and medical photographs, which were confirmed by two clinicians (dermatologists and/or residents). Upon performing this investigation, records from 76 cured patients were finally analyzed.

| Recurrence evaluation
Photos were taken at every visit and reviewed by two doctors to determine the disease activity during the follow-up period. In this study, a cure was defined as ≥80% repigmentation based on lesion area according to the recommendation from the International Initiative for Outcomes (INFO) for vitiligo. 3 Disease recurrence was defined as the spreading of pre-existing lesions and/or the appearance of new lesions.

| Statistics
Statistical analysis was performed using a statistical package (SPSS, Version 18.00). For single-factor comparison, normally distributed measurement data were compared using a t-test, while nonnormally distributed measurement data were compared using the Mann-Whitney U test. Enumeration data were compared using the Chi-squared test, when T≥5 and N≥40, assessed by Pearson's chisquared test; when 1≤T<5 and N≥40, assessed by Yates's correction for continuity; when T<1 or N<40, assessed by Fisher's exact test.
For multiple factors comparison, binary logistic regression analysis was performed to identify risk factors associated with vitiligo recurrence. p ≤ 0.05 was considered statistically significant.

| Recurrence rate in cured patients
In all 76 cured patients, 26 relapsed at different time, with an overall recurrence rate of 34.2%. Among the 26 recurrences, 2 relapsed within three months, 16 relapsed between 3 and 6 months, 2 relapsed between 6 and 12 months, with a 1-year recurrence rate of 26.3%. Besides, 6 relapsed after 12 months (Table 1). In all 26 recurrences, 20 (76.9%) appeared at pre-existing lesions, and 6 (23.1%) appeared at new locations. The result depicts that the recurrence rate increased with time, and the maximum risk of recurrence was observed between 3 and 6 months.

| Comparison of risk factors between recurrence and nonrecurrence patients
We compared the gender, age of onset (yr), age (yr), family history, trauma history, vitiligo type, distribution of onset, season of onset, itch, dyssomnia, sun exposure, other inflammation/autoimmune diseases comorbidities, oral traditional Chinese medicine (TCM) intake, topical corticosteroids, and VIDA score between recurrence and nonrecurrence group. The results show that the age of onset (yr), distribution of onset, and oral TCM are significantly different (p < 0.05) between the two groups ( Table 2).

| Binary logistic regression analysis of risk factors for vitiligo recurrence
As mental stress and complications with other autoimmune diseases could affect vitiligo recurrence, 4 (Table 3).

| DISCUSS ION
Vitiligo is hard to cure clinically. Although cosmetically acceptable (usually defined as >75%) repigmentation can be achieved, the achievement rate is very low. 5 More importantly, disease flare rate remains high even after satisfactory recovery and/or stable state are achieved. Park et al. 6 observed a relapse in 87 SV patients corresponding to a 36.7% had disease recurrence after two years from disease onset, even when the treatment was continued. Majid et al. 7 followed up the incidence of relapse for one year in pediatric patients and demonstrated a 34.8% relapse in 138 complete remission patients after therapy was withdrawn. Nicolaidou et al. 8  propensity to relapse than older patients. 7 Further, an onset age <14 years was reported as a significant risk factor in SV patients but not in NSV patients. 10 Our study found that the recurrence rate was significantly higher in older patients (71.9% in the >16 years old group vs. 16.7% in the <16 years old group, p = 0.046). This is probably due to the early treatment withdrawn or SV type in the two studies, which are not distinguished in our study.
Lesion site is another risk factor not only for disease onset but also for disease relapse in vitiligo. A study in patients with SV found that the recurrence rate in facial SV is significantly higher than in truncal SV. 11 Moreover, a prospective study depicted that the face and neck still have better responses compared with the rest of the body even after relapse. 12

CO N FLI C T O F I NTE R E S T
The author declares that there is no conflict of interest.

DATA AVA I L A B I L I T Y S TAT E M E N T
The data that support the findings of this study are available from the corresponding author upon reasonable request.