Background Patients with rheumatoid arthritis (RA) who have muscle weakness and stiff or painful joints might be at increased risk of falls and fracture.
Objectives The present study aimed to prospectively determine the incidence of clinical fractures and associated risk factors in patients with RA who participated in the TOMORROW study (UMIN000003876) that started in 2010.
Methods We evaluated anthropometric parameters, bone mineral density (BMD), disease activity, RA medication, and the incidence of clinical fractures over a five-year period in 202 patients with RA (mean age, 58.6 y; medication with biological agents, 54.9%) and 202 age- and sex-matched healthy volunteers (controls; mean age, 57.4 y). We compared the incidence of clinical fractures between patients and controls between 2010 and 2015 and analyzed associated risk factors in the patients using multivariate regression analysis.
Results The incidence of clinical fractures did not significantly differ between patients with RA (0.042/person-years; py) and controls (0.034/py) within the five-year period (p=0.35). Fractures sites also did not significantly differ between the two groups. Multivariate logistic regression analysis adjusted for fracture risk factors including age, sex, smoking, and body mass index revealed that low BMD at the thoracic vertebrae (<0.7 g/cm2) was significantly associated with the incidence of clinical fractures (odds ratio [OR], 2.95) in all participants group (Table 1). Although medication with glucocorticoid (GC) at entry was also a significant risk factor for fractures (OR, 2.58), RA morbidity was not (Table 1). Among patients with RA, low BMD at the thoracic vertebrae (<0.7 g/cm2) was the most prominent risk factor for fractures (OR, 4.44; Table 1). Additionally, medication with GC at entry (OR, 2.58) was a significant risk factor for fractures in the patients. A mean GC dose of ≥2 mg/day during the five-year period increased risk for fractures in the patients (OR, 3.48; Table 1).
Conclusions The incidence of clinical fractures did not significantly differ between patients with RA and controls during a period of five years. Low BMD at the thoracic vertebrae and low GC doses are apparently significantly associated with an increased frequency of fractures among patients with RA.
Disclosure of Interest None declared