La tasa de fractura no -vertebral en paciente RA puede estar sobreestimada.
NEW YORK (Reuters Health) Feb 06 - With the exception of hip fractures, women with rheumatoid arthritis (RA) may not have substantially more non-vertebral fractures than their counterparts without RA, researchers from Norway report in the February issue of the Annals of the Rheumatic Diseases.
Dr. Ragnhild Orstavik, of Diakonhjemmet Hospital in Oslo and colleagues compared the incidence of self-reported non-vertebral fractures in 249 women with RA identified in the Oslo RA Register and equal number of matched controls. In both groups, the subjects were about 63 years old and had similar body mass indices.
Overall, there were no significant between-group differences in fracture history. Fifty-three RA patients (21.3%) reported a total of 67 fractures while 50 control patients (20.1%) reported 60 fractures. The overall fracture rates per 100 patient-years were 1.62 and 1.45, in RA patients and controls, respectively.
"The similarity between the two groups in the number of subjects who reported a previous fracture...was striking," the team writes. This was totally "unexpected," Dr. Orstavik told Reuters Health, "as RA patients are known to have an increased frequency of osteoporosis, which was also the case in this study."
They were also surprised to find no increase in wrist fractures in patients with RA compared with controls (23 vs 28, p = 0.55), "fractures that are common in this age and sex group, and considered one of the classic osteoporotic fractures," Dr. Orstavik said.
However, because of the small number of subjects in this study, no strong conclusions can be drawn about individual fracture types, except hip fractures, the team reports. Confirming prior studies, hip fractures occurred significantly more often in RA patients than controls (10 vs 2, odds ratio 9.0).
The researchers also noted a consistent independent relationship between fractures and low bone mineral density but not long-term use of corticosteroids or measures of disease activity. "Our study suggests that BMD is a reliable tool for assessing fracture risk in patients with RA, and to the same extent as that seen in postmenopausal women," they write.
Ann Rheum Dis 2004;63:177-182.
