Interactive effect of sarcopenia and falls on vertebral osteoporotic fracture in patients with rheumatoid arthritis.

Abstract

Whether sarcopenia and falls are a risk factor for vertebral fracture in RA patients has not been demonstrated. This study aimed to explore the incidence of vertebral osteoporotic fracture (VOPF) and its relationship with sarcopenia and falls in RA patients. A total of 474 RA patients and 156 controls were enrolled in this study. Anteroposterior and lateral X-ray examinations of the vertebral column (T4-L4) were used for the semiquantitative assessment of VOPF. Bone mineral density was measured by dual-energy X-ray absorptiometry. Skeletal muscle mass was measured by direct segmental multifrequency bioelectrical impedance analysis (DSM-BIA method). RA patients had an increased risk of sarcopenia (62.4% vs 9.0%, x2 = 47.478, P < 0.001), falls (30.2% vs 3.2%), osteoporosis (OP) (33.5% vs 12.8%, x2 = 134.276, P < 0.001), and VOPF (20.3% vs 3.8%, x2 = 47.478, P < 0.001) than controls. Patients with sarcopenia were more likely to have VOPF than RA without sarcopenia (24.0% vs 14.0%, x2 = 6.802, P = 0.009). RA with sarcopenia and prior falls had the highest incidences of VOPF (36.7%). Older age (OR = 1.056, P < 0.001, 95% CI 1.030-1.083), falls (OR = 2.043, P = 0.003, 95% CI 1.238-3.371), OP (OR = 1.819, P = 0.034, 95% CI 1.046-3.163), and usage of glucocorticoids (GCs) (OR = 1.862, P = 0.022, 95% CI 1.093-3.172) were risk factors for VOPF in RA patients, while a higher skeletal muscle index (SMI) was a protective factor (OR = 0.754, P = 0.038, 95% CI 0.578-0.984) for VOPF in RA patients. The interactive effect of sarcopenia and falls is associated with a higher risk of VOPF in patients with RA.