Epidemiology of Osteoarthritis

Osteoarthritis (OA) is the most common form of arthritis in the United States and is a leading cause of disability. It is typically defined in epidemiologic studies by radiographic findings and consideration of symptoms. Its incidence and prevalence are rising, likely related to the aging of the population and increasing obesity. Risk factors for OA include numerous person-level factors, such as age, sex, obesity, and genetics, as well as joint-specific factors that are likely reflective of abnormal loading of the joints. In studying OA, several methodologic challenges exist that can hamper our ability to identify pertinent relationships.

Key points

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Osteoarthritis (OA) is the most common form of arthritis, with OA of the knee, hand, or hip having a similar prevalence of approximately 20% to 30% of adults in various populations.
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Person-level factors associated with OA include increasing age, female sex, overweight/obesity, and race/ethnicity, which may represent genetic or sociocultural influences.
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Joint-level factors associated with OA are reflective of mechanisms related to abnormal loading of the joints.
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Several methodologic challenges to the study of OA exist, which have affected our ability to identify important relationships.
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There is a need for ongoing epidemiologic and intervention studies regarding the prevention of incident and progressive OA and related pain.