Objective: To clarify the relation between changes in bone density, the treated disease, and dose of corticosteroids prescribed.
Methods: MEDLINE database (1966-95) and bibliographic searches selected cohorts of patients with rheumatoid arthritis (RA) and non-RA patients, studied by reliable serial bone density measurements.
Results: Two randomized controlled trials in early RA found greater lumbar bone loss after corticosteroid treatment (pooled effect size at 6 mo 3.9%; 95% CI: 1.9, 6.0%). The other studies included 66 patients with RA taking mean 7 mg prednisone/day; 371 "untreated" RA patients; and 216 non-RA patients taking mean 20 mg prednisone/day. Lumbar bone mass changed (weighted mean) 0.0% (-0.6, 0.7%) per year in steroid treated RA, -0.6% (-0.9, -0.2%) in untreated RA, and -4.7% (-5.2, -4.3%) in non-RA. Femoral neck changed -3.0% (-4.2, -1.8%), -0.7% (-1.0, -0.3%), and -1.5% (-2.5, -0.4%), respectively. In RA, most bone was lost in the first half year, and in early or uncontrolled disease.
Conclusion: In patients with RA bone loss is limited, influenced by the interaction of disease characteristics and low dose corticosteroid therapy. In contrast, non-RA patients taking higher doses of corticosteriods may loss clinically relevant amounts of bone (i.e., > 5%) within one year.