Prevalence of and annual ambulatory health care visits for pediatric arthritis and other rheumatologic conditions in the United States in 2001-2004

Objective. To estimate the prevalence of and the annual number of ambulatory health care visits for pediatric arthritis and other rheumatologic conditions. Methods. We used physician office visit, outpatient department visit, and emergency department visit data from the 2001-2004 National Ambulatory Medical Care Survey and 2001-2004 National Hospital Ambulatory Medical Care Survey to estimate annual visits for the International Classification of Diseases, Ninth Revision, Clinical Modification codes thought to represent significant pediatric arthritis and other rheumatologic conditions (SPARC). We converted visit estimates into prevalence estimates using data on the number of prior annual visits per patient. Synthetic estimates for states were produced using national rates. Results. The average annualized estimate of the number of children with SPARC was 294,000 (95% confidence interval [95% CI] 188,000-400,000). The annualized number of ambulatory health care visits for SPARC was 827,000 (95% CI 609,000-1,044,000). Conclusion. Pediatric arthritis estimates have varied widely because it is an umbrella term for which there are many definitions and because it is a relatively uncommon condition from a population surveillance perspective. Our estimates suggest that arthritis-related health care visits impose a substantial burden on the pediatric health care system. One advantage of this surveillance paradigm is that it has established a starting point for tracking the national prevalence of arthritis and rheumatologic conditions in children on an ongoing basis using existing infrastructure rather than expensive new surveys. This surveillance system will help us monitor and predict the health care needs of patients with these conditions.