Arthritis and other rheumatic conditions affect 53 million U.S. adults ages 18 and older, are the most common cause of disability, and are associated with considerable pain, activity limitation, and restriction of work and social participation. Projecting changes in the prevalence and impact of chronic diseases, such as arthritis, is crucial for planning future clinical and public health needs, informing health policy and establishing priorities for planning and resource allocation.
The aging of the population has driven previous projections of arthritis prevalence and the associated impact. A new report from the U.S. Census Bureau confirms that aging will remain an important factor in the future: by the time of the 2030 census, all baby boomers will have reached age 65 years, and one in five U.S. adults will be 65 years of age or older.
Previous projections of arthritis prevalence based on 2003 data have tracked well against subsequent arthritis prevalence estimates.
The authors of the study, “Updated Projected Prevalence of Self-Reported Doctor-Diagnosed Arthritis & Arthritis-Attributable Activity Limitation Among U.S. Adults, 2015–2040,” set out to update the projected prevalence of arthritis and arthritis-attributable activity limitations among U.S. adults, using a newer baseline for estimates.
They obtained baseline prevalence data from the 2010–2012 National Health Interview Survey. Arthritis was defined as an answer of “yes” to the question, “Have you ever been told by a doctor or other health professional that you have some form of arthritis, rheumatoid arthritis, gout, lupus or fibromyalgia?” Arthritis-attributable activity limitation was defined as an answer of “yes” to the question, “Are you limited in any way in any of your usual activities because of arthritis or joint symptoms?”
The baseline prevalence of arthritis and arthritis-attributable activity limitation was stratified according to age and sex, and was statistically weighted to account for the complex survey design. The projected prevalence of doctor-diagnosed arthritis and arthritis-attributable activity limitation was calculated by multiplying the age- and sex-stratified population estimates projected for 2015–2040 (in five-year intervals; provided by the U.S. Census Bureau) by the baseline estimates. Age- and sex-specific prevalences were summed to provide the total prevalence estimates for each year.
In 2010–2012, 52.5 million adults in the U.S. (22.7% of all adults) had doctor-diagnosed arthritis, and 22.7 million (9.8%) had arthritis-attributable activity limitation. By 2040, the number of U.S. adults with doctor-diagnosed arthritis is projected to increase 49% to 78.4 million (25.9% of all adults), and the number of adults with arthritis-attributable activity limitation will increase 52% to 34.6 million (11.4% of all adults).