Epidemiology

Vitiligo is amongst the most important acquired depigmentation disorders with an average worldwide prevalence of 0.5% to 2.0%, with specific countries, such as India, reporting prevalence rates of up to 4.0% to 8.8%. The disease can develop at any age; however, in half of all individuals with vitiligo, onset occurs between the ages of 10 and 30 years. A positive family history is present in 7.7% to 50.0% of patients. The mean age of onset tends to be earlier in those with a positive family history.

Skin type

Although vitiligo equally affects people across all races and ethnicities, there is generally a more negative impact on QoL with darker skin types. However, this is not universally true. Porter and Beuf administered questionnaires focused on patient’s emotional reaction toward vitiligo; they distributed the Coopersmith Self-Esteem Inventory tool and stigmatization questionnaire among 158 subjects with vitiligo, 60% white and 40% black. Blacks and whites did not differ in degree of disturbance by the disorder.

Research from different countries indirectly helps to better understand the implications of skin phototype and ethnicity on vitiligo. Most of these studies originate from Western countries and the Middle East, with surprisingly fewer from India where vitiligo was once considered 1 of the top 3 major medical problems in India.

QoL research from Western European countries such as the Netherlands indicate that subjects with darker skin types (skin type IV–VI) showed more health-related QoL (HRQL) impairment using a generic QoL measuring tool (36-Item Dutch Short form [SF-36]) and a dermatology-specific HRQL tool (Skindex-29) compared with their lighter-skinned counterparts. Linthorst Homan and colleagues reported that most individuals with an impaired QoL were immigrants, originally from Suriname, India, Morocco, Turkey, Curacao, Indonesia, China, or Afghanistan, who generally have darker skin types. The Netherlands Institute for Pigmented Disorders also reported on subjects with universal vitiligo (a rare type of extensive generalized vitiligo with more than 80% body surface area [BSA] depigmentation) or generalized vitiligo (the most common form of vitiligo characterized by symmetric widespread distribution of depigmented macules) again using the SF-36 and the Skindex-29. A greater number of individuals with skin phototype I to III with both generalized and universal vitiligo were included than those with skin phototype IV to VI. Statistically significant poorer physical QoL (physical function and bodily pain) was demonstrated in subjects with universal vitiligo when compared with age- and sex-matched subjects with generalized vitiligo. These studies emphasize that several different parameters, such as ethnicity, skin phototype, and extent of disease involvement, can predict negative effects of vitiligo on QoL. A study from Italy including 181 subjects with vitiligo (80% skin type III, 13% skin type II, and 7% skin type IV) showed higher prevalence of probable depression or anxiety (39%) and alexithymia (24%) than the general population (10%). These subjects also had many HRQL problems such as worry of the disease getting worse (60%), anger (37%), embarrassment (34%), feeling depressed (31%), having social life affected (28%), and shame (28%).

Kruger and colleagues enrolled 71 vitiligo subjects, with the majority being skin type III (N = 55), 4 with skin type II, 8 with skin type V, and 2 with skin type IV and VI. The mean Dermatology Quality and Life Index (DLQI) was 7.8 compared with a mean DLQI of 10.67 in a study originating from India that included data from 141 subjects with vitiligo. Although skin types were not specified, it has been suggested that most were likely of darker phenotype (IV–VI). Studies from the Middle East also with a population predominantly of darker phenotypes show similar results. Dolatshahi and colleagues reported significantly higher mean DLQI scores in individuals with skin type V (20.67) than in those with skin type II (5.21), III (8.34), and IV (8.07).

Surprisingly few studies have evaluated QoL in vitiligo in a diverse population with varying skin types as in the United States. A study on pigmentary disorders and their impact on QoL included 140 subjects out of which only 1 had vitiligo. Multiple reviews written on vitiligo discuss the devastating psychosocial consequences on skin of color subjects and try to incorporate psychological intervention in treatment. A disease-specific HRQL instrument for vitiligo is currently being developed. During validation of this instrument, several factors were found to be associated with worse HRQL: female gender, having dark brown or black hair, being single, and self-identifying as Asian. Moreover, age, number of areas of the body affected, and skin type all directly correlated with HRQL (Kundu, personal observation, 2011).

These studies indicate that subjects with darker phenotype have a relative worse HRQL impairment, but subjects with lighter phenotype are still negatively affected.