Objectives: Osteoporosis is a well known extra-articular phenomenon in patients with uncontrolled, longstanding rheumatoid arthritis (RA). In the present study, the extent of osteoporosis and reduced bone mineral density (BMD) and the disease-related and demographic factors that are associated with osteoporosis and reduced BMD are examined in patients with recently diagnosed, active RA.
Methods: BMD of the total hip and the lumbar spine was measured in 381 DMARD and corticosteroid-naïve patients with recently diagnosed, active RA using dual energy x-ray absorptiometry. Osteoporosis was defined as T-score ≤-2.5 SD and reduced BMD as Z-score ≤-1 SD. Multivariate logistic regression analyses were performed to detect associations of osteoporosis and reduced BMD with disease activity, functional disability and joint damage (Sharp/vanderHeijde Score), as well as with demographic factors.
Results: Osteoporosis and reduced BMD were found in 11% and 25%, respectively, of the patients in the spine and/or the hip. Longer symptom duration and presence of rheumatoid factor (RF) were the only RA-specific markers for osteoporosis and reduced BMD. Further, postmenopausal status in females, a low BMI and familial osteoporosis and, remarkably, male gender were independently associated with osteoporosis and reduced BMD.
Conclusion: In DMARD and corticosteroid-naïve patients with recently diagnosed active RA, BMD seems to be well preserved and predominantly related to demographic factors. Longer symptom duration and a positive RF, but not higher disease activity or more joint damage, were related to osteoporosis and reduced BMD.
- bone mineral density
- early rheumatoid arthritis