Study Highlights Global Prevalence of Vitiligo, Regional Trends

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A new study highlights the global impact of vitiligo and uses subgroup analyses to explore prevalence around the world, with investigators concluding that overall prevalence of the skin condition is lower than previously believed and that females and males are equally impacted.¹

These findings and more resulted from a systematic review and meta-analysis led by Morten Bahrt Haulrig from the department of dermatology and allergy at the Herlev and Gentofte Hospital in Denmark.

Haulrig et al. noted that vitiligo is commonly described as widespread, adding that there is an estimated global prevalence ranging from 0.5% - 1%. The investigators also pointed out that the condition was believed to impact all age groups equally, regardless of skin type, sex, or ethnicity.²

“We investigated the incidence and the global, regional, and country-specific prevalence of vitiligo,” Haulrig and colleagues wrote. “Additionally, we investigated the prevalence through subgroup analyses based on age, sex, study type, sample size, study quality and publication year.”

Background and Design

The research team carried out a comprehensive search, using the EMBASE, PubMed, and Web of Science databases and evaluating included records from inception through to August 2023. Specific medical subject headings were implemented in the team’s search, including words such as ‘vitiligo,’ ‘pigmentary,’ and ‘leukoderma.’

The investigators also looked at relevant studies’ references, as well as previously published reviews. Their overall aim was on research that looked into the prevalence and/or incidence of vitiligo among general populations, with 4 study authors independently screening abstracts and titles, thoroughly assessing full-text articles.

The research team only included duplicate studies if they featured different subgroups’ data that was also from the same population. In circumstances in which multiple point prevalence estimates were seen within the same population, the team only considered the most recent data.

Quality and potential risk of bias assessments were also conducted by the investigators, with the team implementing the Appraisal tool for Cross-Sectional Studies (AXIS) and the Newcastle-Ottawa Scale (NOS) for cohort and case-control research. The so-called AXIS tool, made up of 20 items, had been designed to evaluate the results, methods, discussion sections, and biases in cross-sectional research.

Studies assessed by the investigators were classified based on their risk of bias, with the team ranking each study as low (7−9 items met), moderate (4−6 items met), or high (0−3 items met). They additionally categorized the research into predefined subgroups, defining children and adolescents as subjects aged up to 19 years, with adults being categorized as having a minimum age range of 18 years.

Some other subgroups assessed by the research team included study type, sample size (≥5000 participants), patients’ sex, quality of research (low risk of bias), and publication year.

Study Results

Among the 7,838 studies identified first by the team, there were 171 deemed suitable for analysis, and these involved a total of 572,334,973 participants. The investigators reported that vitiligo’s overall incidence rate was 1.59 per 10,000 person-years (95% CI: 0.70−2.83) and that the rate of the disease’s prevalence was 0.40% (95% CI: 0.37−0.44).

In a notable finding, the investigators concluded that there was not a significant distinction between the rates of female subjects (0.50%, 95% CI: 0.36−0.66) and those of males (0.49%, 95% CI: 0.35−0.65). The greatest prevalence was determined to be in West Asia, at 0.77% (95% CI: 0.44−1.10), and the research team concluded that East Asia had the lowest rate of prevalence at 0.12% (95% CI: 0.10−0.14).

In terms of prevalence in specific countries, the investigators found that Jordan was shown to have the highest prevalence at a rate of 1.34% (95% CI: 0.12−3.87). They noted that Sweden had the lowest prevalence rate at 0.19% (95% CI: 0.08−0.34).

In their comparison of age cohorts, the research team reported that children and adolescents were found to have a lower rate of prevalence at 0.27% (95% CI: 0.24−0.31) versus adult patients, among whom the rate of prevalence was 0.70% (95% CI: 0.59−0.81).

Questionnaire-based research was also found by the team to have led to a higher reported rate of prevalence of 0.73% (95% CI: 0.52−0.98) versus examination-based research at 0.59% (95% CI: 0.46−0.73) and register-based research at 0.13% (95% CI: 0.10−0.17).

“The subgroup analysis categorised by study types influenced the prevalence,” they wrote. “There is a lack of incidence studies and prevalence studies conducted in South America, Africa, Central Asia, and Oceania.”

References

1. ^{Haulrig MB, Al-Sofi R, Baskaran S, Bergmann MS, Løvendorf M, Dyring-Andersen B, et al. The global epidemiology of vitiligo: a systematic review and meta-analysis of the incidence and prevalence. JEADV Clin Pract. 2024; 1–10. https://doi.org/10.1002/jvc2.526.}
2. ^{Ezzedine K, Lim HW, Suzuki T, Katayama I, Hamzavi I, Lan CCE, et al. Revised classification/nomenclature of vitiligo and related issues: the vitiligo global issues consensus conference. Pigm Cell Melanoma Res. 2012; 25(3): E1–13. https://doi.orrg/10.1111/j.1755-148X.2012.00997.x.}