Association between balance and falls with spinal osteoporotic fractures in patients with rheumatoid arthritis

Abstract

Objective To investigate the prevalence of balance deficiency and falls in patients with rh-eumatoid arthritis (RA), and to explore the effect of above factors on osteoporotic fracture (OPF). Methods A total of 386 patients with RA and 158 age, gender-matched normal subjects from Jan 2013 to Oct. 2015 were recruited. Antero-posterior and lateral X-rays scanning of vertebral column (T5-L5) were conducted for each individual, and semi-quantity method was used as the standard for determining vertebral OPF. Falls in 296 RA were recorded in details.The balance ability of 263 cases were measured by Berg balance scale. Statistical analysis was performed with ttest and Chi-square text and logistic regression analysis. Results ① The prevalence of vertebral OPF in RA was 17.4%(67/386), which was 4.5 times the prevalence of the control group (6/158, 3.8%) (χ2=17.743, P<0.01). The occurrence rate of falls in RA was 20.3% during the last year (60/296). ② Compared to RA without OPF, patients with OPF had lower Berg balance score (43±14 vs 33±15, t=4.150, P<0.01). Patients with falls also had lower Berg balance scale scorethan that in RA without falls (31±16 vs 41±14, t=4.373, P<0.01). ③ The prevalence of falls during the last year in RA with vertebral OPF was 39.2% (20/51), which was higher than that in RA without OPF (15.7%, 22/140) (χ2=12.036, P=0.01). The prevalence of falls during the last year in RA with Berg balance scale score <40 was 32.5%, which was higher than that in patients with Berg balance scale score≥40 (P<0.01). Incidence of Berg balance scale score <40 in patients with OPF (68.8%, 33/48) was higher than that in group without OPF (29.7%,35/118) (χ2=21.558, P<0.01). ④ Logistic regression analysis found that age [OR=1.064, P=0.001, 95%CI(1.025, 1.103)] and falls [OR=2.735, P=0.021, 95%CI(1.168, 6.407)] were risk factors for OPF in RA patients, while Berg balance scale score [OR=0.957, P=0.016, 95%CI(0.924, 0.992)] was negatively correlated with spinal OPF in RA patients. Conclusion Falls and decreased balance capacity in RA are closely correlated with OPF in RA. Key words: Arthritis, rheumatoid; Postural balance; Osteoporotic fractures; Falls