Musculoskeletal Complications of Hereditary Hemochromatosis: A Case-Control Study

Objective. Arthropathy that mimics osteoarthritis (OA) and osteoporosis (OP) is considered a classic complication of hereditary hemochromatosis (HH) but has never been investigated in a cross-sectional study. We investigated whether HH is associated with increased prevalence of OA and OP and related factors. Methods. A self-administered questionnaire was completed by 306 patients with HH and 304 age and sex-matched unaffected controls. Results. The mean age of patients was 60.1 +/- 11.3 years, and 47.4% were women. More patients with HH than controls had been given a diagnosis of OA: 50.5% vs 28.9% [adjusted OR (aOR) 2.5, 95% CI 1.8-3.6]. Compared with controls, patients with HH had a higher risk of knee (aOR 5.3, 95% CI 1.1-25.6) and hip replacement prosthesis (aOR 5.2, 95% CI 2.2-11.9). More patients than controls had been diagnosed with OP: 23.3% vs 4.6% (aOR 7.3, 95% CI 3.2-17.0). Patients with FM showed an increased prevalence, although not significant, of wrist (aOR 1.7, 95% CI 0.9-3.0) or vertebral fractures (aOR 1.7, 95% CI 0.8-3.8). The severity of iron overload, as defined by a ferritin level > 1000 mu g/l at diagnosis, was associated with OA (p = 0.0005), OP (p = 0.01), presence of hip prosthesis (p = 0.04), wrist fractures (p = 0.002), and vertebral fractures (p = 0.02). Conclusion. This case-control study strongly suggests a significant association among HH, OA, and OP. Joint involvement can be severe, especially in patients with substantially elevated ferritin levels. (First Release August 1 2010; J Rheumatol 2010:37:2145-50; doi:10.3899/jrheum.100234)