Distribution of Arthritis Subtypes Among Adults With Arthritis in the United States, 2017–March 2020

This is the authors' abstract. We don't add key points for this paper.

Introduction: Arthritis is a common chronic disease, affecting an estimated 53.2 million adults (21.2%) in the US. "Arthritis" is a general term, describing over 100 conditions with different etiologies, pathogeneses, symptoms, and treatments. Few studies have examined the prevalence and distribution of arthritis subtypes in the US. Methods: We used National Health and Nutrition Examination Survey data from 2017 to March 2020 to estimate the prevalence of arthritis subtypes overall and by sociodemographic characteristics. Results: The overall prevalence of any type of diagnosed arthritis among US adults aged 20 years or older in this study was 27.9% (67.1 million). Among adults with diagnosed arthritis, osteoarthritis (49.6%, 33.2 million) was the most common arthritis subtype, followed by rheumatoid arthritis (15.8%, 10.6 million) and psoriatic arthritis (1.4%, 1.0 million). More than 1 in 10 reported some other type of unlisted arthritis (11.5%, 7.7 million), and 1 in 5 did not know their arthritis subtype (21.6%, 14.4 million). Prevalence of not knowing arthritis type was approximately 1 in 4 for adults identifying as non-Hispanic Black (26.7%) or other Hispanic (29.5%) and for adults who reported low family income (26.7%) and was approximately 1 in 3 for adults identifying as Mexican American (31.9%), having less than a high school education (31.8%), or not having health insurance (36.1%). Conclusion: Understanding arthritis type is important for improving treatment, self-management, and health outcomes associated with arthritis. Improving organizational and personal health literacy are potential strategies that may reduce the prevalence of not knowing arthritis type.