The global, regional, and national burden of seborrheic dermatitis: results and insights from the Global Burden of Disease 2019 Study.

Seborrheic dermatitis (SD) is a chronic skin disease affecting infants, adolescents, and adults. The cause of SD is not known. Previous studies suggested genetic and environmental roles in the etiology of the disease. However, epidemiological data on SD have been scarce. The study aimed to analyze the burden of SD. We analyzed national and macro-regional SD data from the Global Burden of Disease Study 2019 (GBD 2019) resources. Regression analysis was performed to compute the annual percent change (APC) and identify significant changes in the temporal prevalence trends of SD from 1990 to 2019 relative to age-standardized and crude world population. Pearson correlation test was used to evaluate the association between prevalence and Socio-Demographic Index (SDI) at a macro-regional level. Over the years, from 1990 to 2019, the age-standardized prevalence of SD had a slow growth trend, with an APC of + 0.10% (p < 0.001), while crude prevalence has been showing a greater increase with an APC of +0.32 (p < 0.001). In 2019, the regions with the highest prevalence in the world were Sub-Saharan Africa and North America, while Central Asia and Eastern Europe showed the lowest prevalence. Prevalence distribution by age showed an increase starting at the age class 60-64, then peaked at the age class 80-84, and a subsequent decrease. Males appeared to be slightly more affected than females at older ages. Correlation patterns between prevalence and SDI were not significant. In this study, we found that the prevalence of SD varies between the geographical regions. However, the overall age-standardized prevalence of the disease has been stable throughout 30 years (1990-2019).