Association between body mass index and vitiligo distribution: An observational cohort study

12% vs 6% of nondiabetics in India, and 4.9% in diabetics 3 vs 1.8% of nondiabetic patients in Iran.

To the Editor: Vitiligo is an inflammatory skin condition affecting 0.5% to 2% 1 of the population.A recent meta-analysis of 28,325 patients with vitiligo identified association with diabetes mellitus and obesity. 2 The direct effect of weight on vitiligo severity has yet to be elucidated.We hypothesized that with greater body mass index (BMI) there is greater skin friction, which could result in Koebner phenomenon on the central portion of the body.
Patients self-reported their sex, age, race, vitiligo regions of distribution, height, and weight.Only respondents providing both height and weight as well as proper units were included for analysis.BMI was calculated using the formula: weight (lb)/ (height [in]) 2 3 703 (kg/m 2 ).BMI classifications included underweight for patients with a BMI \18, normal for patients $18 but\25, overweight for[25 and \30, and obese for BMI $30.Analysis was performed with R (version 1.4).
We found a significant stepwise relationship with the increasing presence of stomach and underarm lesions linked to increasing BMI quartile (Fig 1).For the first quartile, a 46% occurrence of vitiliginous lesions on the stomach was noted, but for the fourth quartile there was a 63% occurrence (P \.001).Similarly, for the underarms, the first quartile had 63% occurrence, and the fourth quartile had a 76% occurrence of vitiliginous lesions (P \.001).
The effect of weight on vitiligo extent appears to be a promotional effect.Two recent studies examining patients with type 2 diabetic noted vitiligo in 12% vs 6% of nondiabetics in India, and 4.9% in diabetics 3 vs 1.8% of nondiabetic patients in Iran. 4 A picture is created of vitiligo aggravation by higher BMI in sites of dependence and friction, including folds, waistline, feet, and toes.There are benefits and limitations identified within the survey process.Inherent in all survey processes is the possibility that patients may not provide accurate information.Specifically, it has been demonstrated that patient self-assessment of vitiligo is often not in agreement with physician estimates. 5To reduce this risk, we focused on selfidentification by disease localization.
The relationship between vitiligo, the Koebner phenomenon, and inflammation in the metabolic syndrome requires prospective study.Our findings support prior data showing an association of vitiligo extent and metabolic syndrome.We demonstrated that increased BMI quartile confers increased risk of central disease (axillae, abdomen, chest, and arms).It remains to be seen if weight control can help control disease spread.
Ross O'Hagan, MD, a Samir Kamat, MD, a Shira Wieder, MD, a Marcel Perl, MD, a Jonathan I. Silverberg, MD, PhD, MPH, b and Nanette B. Silverberg, MD a From the Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, New York a ; and Department of Dermatology, George Washington University School of Medicine and Health Sciences, Washington, District of Columbia.b

Table I .
Characteristics of cohort stratified by weight classification *n (%).ª 2024 by the American Academy of Dermatology, Inc. Published by Elsevier Inc.This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).