THE RISK OF OSTEOPOROTIC FRACTURES IN PATIENTS WITH RHEUMATOID ARTHRITIS: RESULTS OF THE PROGRAM «OSTEOSCREENING RUSSIA»

Abstract

Rheumatoid arthritis (RA) and the use of glucocorticoids (GCs) are proven risk factors for osteoporosis (OP) and osteoporotic fractures (OPF). There are also other reasons for increased fracture risk in RA.Objective: to determine the rate of RA in an epidemiological sample of persons aged 50 years and older and to identify those in need of antiosteoporotic therapy among the patients with RA in order to prevent OPF.Subjects and methods. The epidemiological sample included 18,018 people aged 50 years and older (13,941 women and 4,077 men; mean age, 62±10 years). The survey consisted of a unified questionnaire, measurement of daily dietary calcium intake, and calculation of a 10-year fracture risk using the FRAX® algorithm.Results and discussion. The prevalence of RA in the epidemiological population sample aged 50 years and older was 1.7% (1.9% in women and 1.2% in men; p=0.0047). The mean FRAX® values for major OPF in RA patients were significantly higher than those in non-RA individuals: 18.4±10 and 13.2±7.9%, respectively (p=0.0001) for women and 8.9±6.4 and 6.2±3.7%, respectively (p=0.0001) for men. 42% of the patients with RA were at high risk for OPF. Thus, 48% of the women with RA had FRAX® values above the therapeutic intervention threshold; and the non-RA group needed antiosteoporotic therapy significantly less (31%; p=0.00001). At the same time, the detection rate of high-risk OPF in men with and without RA did not differ significantly (8 and 5%, respectively; p>0.05). The most common risk factors (RFs) for OP and OPF in RA patients included previous fractures (33%), secondary causes of OP (30%), GC use (18%), and, additionally, smoking (33%) in male patients with RA. The female patients with RA significantly more frequently took GCs (17%) and had other secondary causes of OP and OPF (33%) than those without RA (7.7% (p=0.0001) and 23% (p=0.0004, respectively). The male patients with RA versus to the population-based control showed significant differences when they only used GCs (20 and 5%, respectively; p = 0.0001); the remaining RFs were encountered at the same frequency. Less than half of the normal daily calcium intake was observed in 20% of men and 16% of women (p=0.53).Conclusion. 42% of the RA patients aged 50 years and older were at high risk for OPF and needed antiosteoporotic therapy. Every third woman with RA had at least one other comorbidity or condition associated with the increased risk of OPF. In the male patients with RA, the FRAX® algorithm could reveal only 8% of persons at high risk for fractures, while 58% of them had two or more additional RFs that can negatively affect bone mineral density and increase the risk of fracture. To identify those who require prevention and treatment of OP and OPF, it is preferable to perform bone densitometry of the axial skeleton among male patients with RA.