Prevalence rates for ectodermal dysplasia syndromes

Background: Ectodermal dysplasias (EDs) are a heterogeneous group of genetic conditions affecting the development and/or homeostasis of two or more ectodermal derivatives, including hair, teeth, nails, and certain glands. There are currently 49 recognized EDs with molecularly confirmed etiology. The EDs are very rare disorders, individually and in aggregate. Very little is published regarding the prevalence of these rare disorders. As a result of the genomics revolution, rare diseases have emerged as a global health priority. The various disabilities arising from rare disorders, as well as diagnostic and treatment uncertainty, have been demonstrated to have detrimental effects on the health, psychosocial, and economic aspects of families affected by rare disorders. Contemporary research methodologies and databases can address what have been historic challenges encountered when conducting research on rare diseases. Objective: In this study, we aim to ascertain period prevalence rates for several of the more common ectodermal dysplasia syndromes, by querying a large multicenter database of electronic health records, Oracle Real-World Data. Methods: For each of the included ectodermal dysplasia syndromes a clinical definition was developed by a committee of international experts with interests in EDs. The clinical definitions were based upon a combination of clinical features and designated by ICD-9 and ICD-10 codes. The January 2023 version of the Oracle Real-World Data database was queried for medical records that coincided with the clinical definitions. For our study, there were 64,523,460 individual medical records queried. Results: Period prevalence rates were calculated for the following ED disorders: hypohidrotic ectodermal dysplasia, found to be 2.99 per 100,000; ectodermal dysplasia and immunodeficiency 1, 0.23 per 100,000; Clouston syndrome, 0.15 per 100,000; ectrodactyly ectodermal dysplasia and cleft lip/palate syndrome, 0.61 per 100,000; ankyloblepharon-ectodermal defects-cleft lip/palate syndrome, 0.36 per 100,000; focal dermal hypoplasia, 0.10 per 100,000; and incontinentia pigmenti, 0.88 per 100,000. Conclusion: This study established estimated period prevalence rates for several of the ectodermal dysplasia syndromes, and it demonstrated the feasibility of utilizing large multicenter databases of electronic health records, such as Oracle Real World Data.