Association between BMI and Vitiligo Distribution: An Observational Cohort Study

Abstract Vitiligo is an inflammatory skin condition affecting 0·5–2% of people. Previous studies have found that vitiligo does not appear to have an association with an increased body mass index (BMI) nor is BMI a risk factor for vitiligo. However, to the best of our knowledge, the relationship between a patient being over or underweight and the presentation of vitiligo has not been explored. Here, we aim to explore the relationship between BMI classifications and vitiligo distribution. A total of 1685 consecutive patients with vitiligo were recruited as part of an ongoing survey study. Patients self-identified their sex, age, race and regions of vitiligo distribution. Patients reported their height and weight, which was then used to generate BMI values, which were then grouped into classifications. The BMI classifications were underweight for patients with a BMI >18·5, normal for patients with a BMI equal to 18·5 or larger but <30 and overweight for patients with a BMI equal to or over 30. Analysis was performed with R (version 1·4). The cohort (n = 1685) had a median age of 42 years, was predominantly female (72%) and was predominantly white (64%). The patients were divided into three weight classes: 1270 normal weight, 344 overweight and 71 underweight. Vitiligo presentation was more likely for overweight individuals in the chest (P = 0·007), stomach (P < 0·001), underarms (P = 0·005), arms (P = 0·007), elbows (P = 0·031), wrists (P = 0·040), hands (P = 0·003), fingers (P = 0·004), buttocks (P = 0·002), ankles (P = 0·033), feet (P < 0·001) and toes (P = 0·022). Vitiligo presentation does not seem to have a relationship with one’s BMI classification in the distribution of the eyelids, lips, mouth, back, hips, genitals, legs and knees. Our preliminary analysis supports that there is a relationship between a patient’s body mass classification and the distribution of vitiligo. Vitiligo presentation seems to be more likely for overweight individuals in the chest, stomach, underarms, arms, elbows, wrists, hands, fingers, buttocks, ankles, feet and toes. Vitiligo presentation does not seem to have a relationship with one’s BMI classification in the distribution of the eyelids, lips, mouth, back, hips, genitals, legs and knees. The effect of weight-induced friction and metabolic syndrome on vitiligo disease progression needs to be explored further. Further studies are needed to explore the varying presentation of vitiligo in individuals of all BMI subtypes and whether weight can help reduce the spread of the disease.