Dercum’s Disease: Estimating the prevalence of a rare painful loose connective tissue disease

Abstract Background In the United States (US), the Orphan Drug Act of 1983 defines a rare disease as affecting less than 200,000 individuals. In Europe, a rare disease or disorder is defined as affecting 5 individuals in 10,000 which the European commission reports to be approximately 246,000 individuals. Dercum’s disease, also known as Adiposis Dolorosa, is a rare loose connective (fat) tissue disease that is characterized by painful lipomas (fatty masses). Orphanet, the National Organization for Rare Disease (NORD) and the United States National Institutes of Health (NIH) have classified Dercum’s disease as a rare disorder. The prevalence of Dercum’s disease is not well studied or understood. The objective of this paper is to estimate the prevalence of Dercum’s disease, whether it is in fact a rare disease, and increase awareness for this painful disease. Results An in-depth literature review was conducted in PubMed, the UK Biobank, the U.S. Agency for Health Research and Quality Healthcare Cost and Utilization, by incidence of disease in medical practice, in social media forums and by internet search in order to understand, estimate and determine the prevalence of Dercum’s disease. The prevalence of Dercum’s disease was found to range from 150 to 150,000 in the US population. Conclusion The data collected in this paper meet the requirements of the Orphan Drug Act which requires 200,000 individuals or less to be affected by a disorder for it to be classified as rare. These conclusions may apply to Europe as supporting data was utilized from both Sweden and the UK. Further research must be conducted to better understand subclassifications of this rare disorder.