Point prevalence of hip symptoms, radiographic, and symptomatic OA at five time points: The Johnston County Osteoarthritis Project, 1991–2018

OBJECTIVE: To describe the point prevalence of hip symptoms, radiographic hip osteoarthritis (rHOA), severe rHOA, and symptomatic rHOA (sxHOA) at five time points in the longitudinal, population-based Johnston County Osteoarthritis Project (JoCoOA). DESIGN: Data were from 3068 JoCoOA participants who attended up to five study visits (1991–2018). Standardized supine pelvis radiographs were read by a single, expert musculoskeletal radiologist with high reliability. The four outcomes were: 1) self-reported hip symptoms: “On most days, do you have pain, aching, or stiffness in your right/left hip?“; 2) rHOA: Kellgren-Lawrence grade (KLG) of 2–4; 3) severe rHOA: KLG of 3–4; and 4) sxHOA: both symptoms and rHOA in the same joint. Weighted point prevalence and 95% confidence intervals (CI) were generated overall and by age group (45–54, 55–64, 65–74, 75+ years), sex, race (Black/White), and body mass index (BMI; 18.5–24.9; 25–29.9; 30+ kg/m(2)). RESULTS: At the most recent follow-up (2017–2018), the point prevalence (%) of hip symptoms, rHOA, severe rHOA, and sxHOA were 30% (95% CI 25%, 35%), 53% (95% CI 48%, 58%), 9% (95% CI 6%, 12%), and 15% (95% CI 11%, 19%), respectively. RHOA and severe rHOA were most prevalent in those 75+ years. Women were more likely than men to have hip symptoms and sxHOA. No consistent trends were noted by race or BMI. CONCLUSION: These updated point prevalence estimates demonstrate a large and increasing burden of HOA in the general population, particularly with aging. Black and White individuals were affected similarly in this cohort.