Incidence rate of falls and its risk factors in patients with rheumatoid arthritis compared to controls: Four years of the TOMORROW study

Abstract

Objective: Patients with rheumatoid arthritis (RA) have been recognized to experience falls frequently due to functional disabilities. The aim of this study was to prospectively investigate factors influencing falls in patients with RA compared to controls.

Methods: We compared the frequency of falls in 208 RA patients and 205 age- and sex-matched volunteers for four years and analyzed risk factors for falls in RA patients using multivariate regression analysis.

Results: No significant difference in the incidence rate of falls (/person-year) between patients with RA (median [interquartile range]: 0 [0, 0.5]) and controls (0 [0, 0.5]) was evident during four years. Logistic regression analysis identified age, sex, body mass index, history of falls, and lower limb implant at baseline as significant risk factors for falls. The highest quartile of anti-CCP antibody level (>300.6 U/ml) was the strongest predictor for multiple falls (odds ratio, 2.97; 95% confidence interval, 1.12–7.91, p = 0.029) among RA patients.

Conclusion: During four years we could not observe the higher incidence rate of falls in RA patients compared to controls in our cohort. Subjects with a higher titer of anti-CCP antibody might be at higher risk of frequent falls among RA patients.

Keywords:

• Anti-cyclic citrullinated peptide antibody
• Cohort study
• Fall
• Rheumatoid arthritis

Acknowledgements

We wish to thank Atsuko Kamiyama, Tomoko Nakatsuka, and the Center for Drug & Food Clinical Evaluation, Department of Radiology and Department of Central Clinical Laboratory in Osaka City University Hospital for their special efforts as research coordinators in recruiting subjects, collecting data, and managing the quality of data. We greatly appreciate the cooperation of the patients with RA and volunteers who participated in this study.

Conflict of interest

Dr. Koike has received grant fees, research fees, consulting fees, or other remuneration from AbbVie, Astellas Pharma, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Janssen, Lilly, Mitsubishi Tanabe Pharma Corporation, MSD, Ono Pharmaceutical, Pfizer, Roche, Takeda Pharmaceutical, Teijin Pharma, and UCB. All other authors have declared no conflicts of interest.