A new
“The remarkably high number of participants with undiagnosed vitiligo” indicates a need for “the development and validation of teledermatology apps that allow for potential diagnosis,” Kavita Gandhi, MS, of the patient and health impact group at Pfizer in Collegeville, Pa., and associates said in JAMA Dermatology.
The estimated range of 0.76%-1.11% prevalence represents 1.9 million to 2.8 million adults with vitiligo in the general population, based on responses from 40,888 participants surveyed between Dec. 30, 2019, and March 11, 2020, and further physician evaluation of photos uploaded by 113 respondents, they explained. The investigators used a representative sample of the U.S. population, of people ages 18-85 years.
A prior vitiligo diagnosis was reported by 314 participants, and another 249 screened positive through the survey, for a self-reported overall prevalence of 1.38% in the adult population and a previously undiagnosed prevalence of 0.61%. The physician adjudication brought the overall prevalence down to 0.76% and the undiagnosed prevalence to 0.29%. “These findings suggest that up to 40% of adults with vitiligo in the U.S. may be undiagnosed,” the investigators wrote.
Survey questions covering the laterality of lesions broke the 1.38% overall prevalence down to 0.77% nonsegmental vitiligo (self-reported as bilateral) and 0.61% segmental (unilateral). The 0.76% overall prevalence provided by the three dermatologist reviewers worked out to 0.58% classified as nonsegmental and 0.18% as segmental, Ms. Gandhi and associates said.
“The distinction between segmental and nonsegmental vitiligo is of prime importance [since] patients are usually concerned by the spreading of the disease and its unpredictable course, which is the hallmark of nonsegmental vitiligo,” the researchers noted.
The analysis was the first, to the authors’ knowledge, to identify several trends among the undiagnosed population. The proportion of nonwhite adults was higher in the undiagnosed group (40.2%) than among those with a diagnosis (31.5%), as was Hispanic, Latino, or Spanish origin (21.3% vs. 15.3%). Unilateral presentation was seen in 54.2% of the undiagnosed adults and 37.3% of those with diagnosed vitiligo, they reported.
The study was sponsored by Pfizer, which employs several of the investigators. Two of the investigators disclosed multiple conflicts of interest involving other companies.