ORIGINAL ARTICLE A Randomized Controlled Trial to Investigate the Effects of Water-Based Exercise to Improve Falls Risk and Physical Function in Older Adults With Lower-Extremity Osteoarthritis Leigh A. Hale, PhD, Debra Waters, PhD, Peter Herbison, DSc ABSTRACT. Hale LA, Waters D, Herbison P. A random- ized controlled trial to investigate the effects of water-based exercise to improve falls risk and physical function in older adults with lower-extremity osteoarthritis. Arch Phys Med Re- habil 2012;93:27-34. Objective: To investigate the efficacy of a water-based exer- cise program specifically targeting balance to reduce falls risk and improve measures of balance and physical function in older adults with osteoarthritis (OA). Design: Randomized controlled trial. Setting: Community. Participants: Persons (N=39; meanSD age, 746y; 26 women) with mild to moderate OA and at risk for falling met study criteria, were measured at baseline, and were randomly assigned to the intervention (n=23) and control groups (n=16). Interventions: Water-based program (12wk, twice weekly; intervention group) or a time-matched computer training pro- gram (control group). Main Outcome Measure: The primary outcome was the short- form Physiological Profile Assessment (PPA). Secondary out- comes included the Step Test, Timed Up and Go Test, Western Ontario and McMaster Universities OA Index (Likert 3.0 ver- sion), Arthritis Impact Measurement Scales 2, and Activity- specific Balance Confidence Scale. Results: No statistically significant between-group differ- ences were found for any outcome measured (n=35; 4 lost to follow-up). Within-group analysis indicated that Step Test re- sults improved significantly in both groups (mean change: control group, left leg, 2.07; 95% confidence interval, 3.19 – .95; P=.002; intervention group, 2.14; 95% confidence inter- val, 3.20 –1.08; P=.000). Two PPA item scores (reaction time, contrast sensitivity) improved significantly (86.83; 95% confi- dence interval, 9.86 –163.79; P=.03; 1.43; 95% confidence interval, 2.35–.50; P=.005, respectively) in the control group, resulting in a lower falls risk score. Conclusions: Water-based exercise did not reduce falls risk in our sample compared with attending a computer skills training class. Our study is, to our knowledge, the first to compare water-based exercise in this population with a control group that attended a time-dose– equivalent seated community-based activity. Whether gaining computer skills and going out into the community twice weekly is adequate stimulus to reduce falls risk in people with OA requires further investigation. Key Words: Balance; Falls risk; Older adults; Osteoarthri- tis; Rehabilitation; Water-based exercise. © 2012 by the American Congress of Rehabilitation Medicine A PPROXIMATELY 30% of our population 65 years or older experience at least 1 fall a year, and this risk is greater in persons with lower-extremity osteoarthritis (OA). 1,2 Exercise programs have been designed to prevent falls in older adults. 3,4 However, traditional land-based exercises may not be suitable for persons with OA because these could aggravate joint pain. Exercise in water is an alternative because it has the benefit of placing less stress on joints, as well as reducing the risk for falling inherent in land-based exercise. Water-based exercise was shown to have beneficial effects in older adults. For healthy older women, Tsourlou et al 5 reported that a thrice-weekly water training program for 24 weeks significantly improved strength, trunk flexion, jumping ability, and functional mobility compared with a nonexercising control group. In frail older adults, functional independence and qual- ity of life were improved by both once- and twice-weekly water exercise programs. 6,7 Water-based exercise also has short-term benefits for older adults with hip and/or knee OA. 8 This Co- chrane review 8 included 6 studies in which water-based exer- cises were aimed at stretching, strengthening, aerobic capacity, and gait retraining; exercises targeting balance were not in- cluded. Similarly, Silva et al 9 compared a water-based program with a land-based program in participants with OA of the knee and showed significant reductions in pain on walking in the water-based group. Exercises focused on stretching, strength- ening, and gait retraining. Studies have investigated the effect of water-based exercise on balance in many types of participants, including those with OA. Suomi and Koceja 10 found that a 6-week program adher- ing to the Arthritis Foundation Aquatic Program guidelines resulted in significant improvement in postural sway in women aged 45 to 70 years with either OA or rheumatoid arthritis. From the School of Physiotherapy and Centre for Physiotherapy Research (Hale) and Preventive and Social Medicine (Waters, Herbison), University of Otago, Dun- edin, New Zealand. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or on any organi- zation with which the authors are associated. Reprint requests to Leigh A. Hale, PhD, School of Physiotherapy, University of Otago, PO Box 56, Dunedin, 9054 New Zealand, e-mail: leigh.hale@otago.ac.nz. 0003-9993/12/9301-00300$36.00/0 doi:10.1016/j.apmr.2011.08.004 List of Abbreviations ABC Activity-specific Balance Confidence (Scale) AIMS2-SF Arthritis Impact Measurement Scales 2- Short Form (26 Items) GP general practitioner ICC intraclass correlation coefficient OA osteoarthritis PPA Physiological Profile Assessment RCT randomized controlled trial TUG Timed Up and Go WOMAC Western Ontario and McMaster Universities Osteoarthritis Index 27 Arch Phys Med Rehabil Vol 93, January 2012