The aim of this study was to evaluate the bone mineral density (BMD) in patients with early rheumatoid arthritis (RA) prior to and 6 months after adding low-dose corticosteroid (CS) treatment. Adult patients (>21 years old) with early RA (symptom duration <1 year) and severe joint pain under maximal dose of nonsteroidal anti-inflammatory drugs (NSAIDS) were started on low-dose prednisone (10 mg/day). Patients were evaluated after 1, 3, and 6 months. Disease activity measures including swollen and tender joint count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were documented, and the dose of prednisone was adjusted according to the level of pain at each visit. BMD of the femoral neck (FN) and lumbar spine (LS) was measured using dual energy X-ray absorptiometry prior to and 6 months after starting CS treatment. Calcium supplements, vitamin D, bisphosphonates, or hormonal therapy that may affect BMD were not permitted during the study. Twenty patients were eligible and 16 completed the study; 75% were female. The mean age was 47.2+/-12 years and mean duration of symptoms was 7+/-2 months. The mean BMD at the FN prior to and 6 months after starting CS treatment were 0.8080 g/cm(2)+/-0.1145 and 0.8242 g/cm(2)+/-0.1122, respectively (p=0.04). The mean BMD at the LS prior to and 6 months after starting CS treatment were 0.9429 g/cm(2)+/-0.1406 and 0.9490 g/cm(2)+/-0.1277, respectively (p=0.423). There was a significant correlation between the mean change of BMD at the FN and mean change of tender joint count (p=0.01), ESR (p=0.008), and CRP (p=0.006) but not with swollen joint count (p=0.099). However, there was no correlation between the change of BMD at the FN or LS and the change of any of the disease activity measures of every patient. Also, no correlation was seen between the cumulative dose of CS and the change in BMD. BMD increases significantly at the FN in early RA patients 6 months after adding low-dose CS to the treatment.