Fractures of vertebrae and peripheral bones in patients with rheumatoid arthritis (based on long-term observation)

Abstract

Introduction. In rheumatoid arthritis (RA), fractures occur on average 2–3 times more often than in the general population. Data on the incidence of vertebral fractures in RA is controversial and depends on the detection method. Aim. To determine the incidence of vertebral and peripheral bone fractures in patients with RA during long-term prospective follow-up. Materials and methods. A prospective multi-year cohort non-interventional study included 120 women with RA (mean age at enrollment 54.3±8.9 years), with a follow-up of 9.5±1.9 years. Initially and then repeatedly, a clinical, laboratory and radiological examination was performed: X-ray morphometry of the spine according to the Genant method, X-ray densitometry of the lumbar spine (LI-LIV) and femoral neck. Results. During the follow-up period, there were 104 low-energy fractures in 64 (53%) patients: 69 (66%) vertebral fractures and 35 (34%) peripheral fractures. Two or more fractures occurred in 25 (39%) subjects. In 30 (25%) patients, 52 fractures occurred repeatedly. Among peripheral fractures, the most frequent localization was fractures of the distal forearm and lower leg bones. Patients with fractures during the follow-up period were also more likely to have fractures before enrollment in the study, had an initially longer duration of RA, a mean daily dose, cumulative dose, and duration of glucocorticoid administration, and a lower bone mineral density in the main parts of the skeleton, determined by densitometry. There was no effect of RA activity on DAS-28, rheumatoid factor positivity, or antibodies to cyclic citrullinated peptide on fractures. Conclusion. More than half of the patients had low-energy fractures during the observation period, the most common being fractures of the vertebrae, distal forearm, and lower leg bones; a high frequency of repeated fractures was reported. The analysis of risk factors showed that a long duration of RA, a mean daily dose, cumulative dose, and prolonged use of glucocorticoids, a history of low-energy fractures, and low bone mineral density were associated with the occurrence of fractures in patients with RA.