VERTEBRAL OSTEOPOROSIS IN RHEUMATOID ARTHRITIS PATIENTS: EFFECT OF LOW DOSE PREDNISONE THERAPY

The effect of low dose prednisone therapy on spinal bone massis controversial. We measured lumbar trabecular and corticalbone mineral density (BMD) in 74 rheumatoid arthritis (RA) patientsby dual energy quantitative computerized tomography in a cross-sectionalstudy. The presence of vertebral deformities was evaluated ona lateral spine radiograph. Patients who had never been treatedwith corticosteroids (n=44) were compared with patients on long-termlow dose ( 10 mg/day) prednisone therapy (n=30). After correctionfor confounding variables the lumbar BMD was highly sig nilicantlyinfluenced by prednisone therapy in postmenopausal patients(estimated influence –31.2% on trabecular BMD and –37.2%on cortical BMD). Vertebral deformities were also significantlymore frequent in prednisone treated postmenopausal patients.No negative effect of prednisone treatment could be demonstratedin male patients. In contradiction to previous reports we concludethat long-term prednisone therapy may be associated with developmentof spinal osteoporosis in postmenopausal RA patients, even whenlow doses are used. KEY WORDS: Corticosteroids, Osteoporosis, Bone densitometry, Dual energy quantitative computerized tomography, Vertebral fractures, Postmenopause