Prevalence of hidradenitis suppurativa among patients with Down syndrome: a population-based cross-sectional analysis

BackgroundHidradenitis suppurativa (HS) has been linked to Down syndrome (DS). ObjectivesTo determine whether patients with DS have a higher prevalence of HS, and whether the diagnosis of HS occurs at an earlier age for these patients. MethodsA cross-sectional analysis was performed for a population sample of 11936 patients with DS and 16813290 patients without DS. The primary outcome was the diagnosis of HS. Systemized Nomenclature of Medicine-Clinical Terms were used to identify patients with DS and HS. We used logistic regression models and significant interaction terms to evaluate the relationship between DS and HS. We also compared the proportion of incident HS cases within 5-year age groups to determine whether patients with DS had received an earlier diagnosis of HS. ResultsPrevalence of HS among patients with DS was 21%, compared with 03% for patients without DS (P<0001). HS prevalence was greatest among patients with DS who were aged 18-29years. After controlling for age, sex and obesity, there was no difference in the prevalence of HS between female and male patients with DS or between white and nonwhite patients with DS. Compared with patients without DS, patients with DS had increased odds of HS in unadjusted [odds ratio (OR) 784, 95% confidence interval (CI) 693-888] and adjusted (OR 524, 95% CI 462-594) analyses. HS was diagnosed by the age of 29years in 818% of patients with DS, compared with 340% of patients without DS (P<0001). ConclusionsHS is strongly associated with DS across demographic subgroups and may present earlier in life for these patients. What's already known about this topic? Evidence suggests a potential genetic link that predisposes patients with Down syndrome (DS) to the development of hidradenitis suppurativa (HS). There is limited observational data to support this association. What does this study add? In this population-based cross-sectional analysis, a prevalence of 21% for HS was observed in patients with DS. Patients with DS were over five times more likely to develop HS compared with patients without DS. HS is diagnosed earlier in life for patients with DS. Linked Comment:Micheletti. Br J Dermatol 2018; 178:587-588. Plain language summary available online Respond to this article