NIH News Release
National Institute of Arthritis and
Musculoskeletal and Skin Diseases

Tuesday, May 5, 1998
9:00 AM Eastern Time

Connie Raab or
Ray Fleming
(301) 496-8190

Arthritis Prevalence Rising as Baby Boomers Grow Older
Osteoarthritis Second Only to Chronic Heart Disease in Worksite Disability
An estimated 40 million Americans have some form of arthritis or other rheumatic condition. That number is expected to climb to 59.4 million, or 18.2 percent of the population, by the year 2020, according to a new report published as a collaborative effort between the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), the Arthritis Foundation, and the American College of Rheumatology. This increase is largely due to the aging of the U.S. population.

While risk increases with age, arthritis B a broad set of disorders B is not limited to the elderly. More than one-half of the people who reported having arthritis were under age 65. Osteoarthritis is the most common form of arthritis, affecting 12.1 percent of U.S. adults or 20.7 million people. Also known as degenerative joint disease, osteoarthritis was the second most common diagnosis, after chronic heart disease, leading to Social Security disability payments due to long-term absence from work.

"Arthritis is a leading cause of disability. With the aging of the population, it will increasingly burden individuals as well as the economy. This report should draw attention to the escalating impact of arthritis and will help us plan future research and prevention efforts," says Stephen I. Katz, M.D., Ph.D., director of the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), the component of the National Institutes of Health (NIH) that led the study.

Published in the May issue of Arthritis & Rheumatism, the report provides the best available prevalence estimates for a number of important rheumatic and musculoskeletal disorders in the U.S. population. It updates a 1989 report and includes estimates for disorders not included in the earlier report, such as fibromyalgia, low back pain, polymyalgia rheumatica, and giant cell arteritis.

The report was developed by the National Arthritis Data Workgroup. The Workgroup, organized by NIAMS to provide a single source of national data on the prevalence and socioeconomic impact of the rheumatic disorders, comprises 14 experts in rheumatology and epidemiology from U.S. universities and medical centers; NIAMS; the National Center for Chronic Disease Prevention and Health Promotion, of the CDC; the national voluntary health organization, the Arthritis Foundation; and the national professional association, the American College of Rheumatology.

The report focuses on estimates of prevalence or existing cases of each disorder rather than incidence, which counts only the number of new cases within a given period of time. National prevalence estimates were calculated by applying data from several studies to the 1990 Census, the most recent population estimates available.

The data in the report are conservative estimates based on carefully collected national data, such as the National Health and Nutrition Examination Surveys (NHANES) conducted by the CDC's National Center for Health Statistics (NCHS), or uniformly collected data from well-defined small populations. In the report, the authors are careful to point out the limitations of each data source. For example, some of the rheumatic diseases are difficult to classify, and some of the data from national surveys are based on self-reported conditions rather than physical examination. In a few cases, the data extrapolated from small population-based studies may not reflect the racial and ethnic profile of the United States.

"It is very difficult to get reliable estimates for relatively rare disorders," explains NIAMS Epidemiology Program Officer Reva C. Lawrence, MPH, lead author of the report. For many of the rheumatic disorders, such as scleroderma and juvenile rheumatoid arthritis, cases are not regularly reported to state health departments. NIAMS is supporting registries on rare diseases to improve disease monitoring and understanding of these conditions. NIAMS is also working to ensure appropriate emphasis on arthritis in the Healthy People 2010 objectives for the nation, which are currently being developed by the Department of Health and Human Services, of which NIH and CDC are a part.

Additional Estimates:


Lawrence RC, Helmick CG, Arnett FC, Deyo RA, Felson DT, Giannini EH, Heyse SP, Hirsch R, Hochberg MC, Hunder GG, Liang MH, Pillemer SR, Steen VD, Wolfe F. Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States. Arthritis Rheum 1998;41:778-99.

CDC. Prevalence and impact of arthritis by race and ethnicity - United States, 1989-1991. MMWR Morb Mortal Wkly Rep 1996;45:373-8.

National Arthritis Data Workgroup. Arthritis prevalence and activity limitation -- United States, 1990. MMWR Morb Mortal Wkly Rep 1994;43:433-8.

Lawrence RC, Hochberg MC, Kelsey JL, McDuffie FC, Medsger TAJr, Felts WR, Shulman LE. Estimates of the prevalence of selected arthritis and musculoskeletal diseases in the United States. J Rheumatol 1989;16:427-41.

The National Institute of Arthritis and Musculoskeletal and Skin Diseases, a component of the National Institutes of Health, leads the Federal medical research effort in arthritis and other rheumatic diseases, and in musculoskeletal and skin diseases. The NIAMS supports research and training throughout the United States as well as on the NIH campus in Bethesda, Maryland, and disseminates health and research information. Press contact: Connie Raab/Ray Fleming (301) 496-8190.

The Centers for Disease Control and Prevention is the agency of the Federal Government charged with promoting health and quality of life by preventing and controlling disease, injury, and disability. Press contact: CDC Office of Communications (404) 639-3286.

The Arthritis Foundation is the national voluntary health organization devoted to arthritis. Its mission is to support research to find the cure for and prevention of arthritis and to improve the quality of life for those affected by arthritis. Press contact: Carol Galbreath (404) 872-7100 x6365.

The American College of Rheumatology is an organization of physicians, health professionals, and scientists that provides education, research, and advocacy to foster excellence in the care of people with arthritis and rheumatic and musculoskeletal diseases. Press contact: Kelly Sheehan (404) 633-3777.