Estimation of prevalence of autoimmune diseases in the United States using electronic health record data

Previous epidemiologic studies of autoimmune diseases in the United States (US) have included a limited number of diseases or used meta-analyses that rely on different data collection methods and analyses for each disease. To estimate the prevalence of autoimmune diseases in the US, we used electronic health record data from six large medical systems in the US. We developed a software program using common methodology to compute the estimated prevalence of autoimmune diseases alone and in aggregate that can be readily used by other investigators to replicate or modify the analysis over time. Our findings indicate that over 15 million people, or 4.6% of the US population, have been diagnosed with at least one autoimmune disease from January 1, 2011, to June 1, 2022, and 34% of those are diagnosed with more than one autoimmune disease. As expected, females (63% of those with autoimmune disease) were almost twice as likely as males to be diagnosed with an autoimmune disease. We identified the top 20 autoimmune diseases based on prevalence and according to sex and age. Thus, we provide, for the first time, a large-scale prevalence estimate of autoimmune disease in the US by sex and age. Autoimmune Registry Inc., the National Heart Lung and Blood Institute, the National Center for Advancing Translational Sciences, the Intramural Research Program of the National Institute of Environmental Health Sciences.