Bhawani Shankar Jandu, Lekshmi Minikumari Rahulan, Nithin Gowda Av, Rudrarpan Chatterjee, Durga Prasanna Misra, Able Lawrence, Amita Aggarwal
Hip arthritis was more common in ERA than adult SpA even after adjustment for disease duration. Disease duration was independently associated with total hip replacement in patients with hip arthritis. Key Points • Hip arthritis is more common in ERA than in adult SpA and is more often bilateral. • Grade of sacroiliitis and disease duration have dose response relationship with development of hip arthritis in both ERA and adult SpA. • Longer disease duration is associated with the need for total hip replacement in spondyloarthritis.
BACKGROUND: The presence of hip arthritis in spondyloarthropathies (SpA) suggests a severe disease. Data on comparative burden, outcome, and associated factors of hip involvement in juvenile and adult SpA is limited.
METHODS: This was a cross-sectional, observational study involving patients with enthesitis-related arthritis (ERA) (n = 513) and adult SpA (n = 504) attending a tertiary-care rheumatology department. Clinical data including demographics, musculoskeletal involvement, HLA-B27 status, medication use, and (total hip replacement) THR were recorded. Data were analyzed using descriptive statistics and multivariate logistic regression models.
RESULT: ERA patients had longer disease duration at last visit (median 9 vs 6.5 years). Hip arthritis prevalence was higher in ERA than adult SpA (29.2% vs 18.5%; p < 0.001). In pooled multivariable analysis (n = 703), ERA (adjusted OR 1.97, 95% CI 1.37-2.83; p = 0.001), longer disease duration (OR per year 1.04, 1.02-1.06; p = 0.001), and sacroiliitis (OR 2.49, 1.47-4.23; p = 0.001) were independently associated with hip arthritis. Sacroiliitis grade had a direct relationship with prevalence of hip arthritis, each one grade increased odds of hip arthritis by 73% (adjusted OR 1.73, 1.29-2.31; p < 0.001). THR was performed in 4.5% ERA and 2.6% SpA patients. Only disease duration was independently associated with THR (adjusted OR per year 1.07, 1.03-1.11; p = 0.003).
CONCLUSION: Hip arthritis was more common in ERA than adult SpA even after adjustment for disease duration. Disease duration was independently associated with total hip replacement in patients with hip arthritis. Key Points • Hip arthritis is more common in ERA than in adult SpA and is more often bilateral. • Grade of sacroiliitis and disease duration have dose response relationship with development of hip arthritis in both ERA and adult SpA. • Longer disease duration is associated with the need for total hip replacement in spondyloarthritis.