To update the projected prevalence of arthritis and arthritis-attributable activity limitations among US adults, using a newer baseline for estimates.
Baseline prevalence data were obtained 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 5-year intervals; provided by the US 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 US (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 US 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).
Updated projections suggest that arthritis and arthritis-attributable activity limitation will remain large and growing problems for clinical and public health systems, which must plan and create policies and resources to address these future needs.