FIVE TIMES SIT TO STAND TEST IS A PREDICTOR OF RECURRENT FALLS IN HEALTHY COMMUNITY‐LIVING SUBJECTS AGED 65 AND OLDER

To the Editor: Falls are a leading cause of disability, injury, and death in elderly people, occurring each year in more than 30% and 50% of the population aged 65 and 80 older, respectively.1 The use of several clinical balance tests has been widely proposed in primary care to identify elderly subjects with postural instability and at high risk of falling, but the value of these tests in predicting falls remains unclear. The aim of this prospective study was to investigate whether standard clinical balance tests—One-Leg Balance (OLB), Timed “Up & Go” (TUG), and Five Times Sit to Stand (FTSS)—combined with demographic and medical data, predict risk of recurrent falls in community-living subjects aged 65 and older. This population-based study included 2,735 consecutive voluntary subjects aged 65 and older in an apparently good state of health consulting for a medical examination2 between January 2004 and June 2005 at the Centre de Médecine Préventive in Nancy, France. During the medical examination, the subjects performed the following clinical balance tests: OLB test: Subjects were instructed to remain upright on one leg without support for at least 5 seconds.3 TUG test: Subjects were observed and timed while rising from an arm chair, walking 3 m, turning, walking back, and sitting down again (normal duration <12 seconds).4 FTSS test: Subjects were instructed to stand up from a chair five times as quickly as possible without pushing off.5 The seat height for the chair was 45 cm. Falls were recorded using a self-questionnaire completed 18 to 36 months after the visit. Subjects were classified into three groups: nonfallers, single fallers (1 fall), and recurrent fallers (≥2 falls). Information about falls was received from 1,958 subjects (72% of the total sample, mean age 70±4; 978 women); 239 subjects (12.2%) reported one fall and 183 (9.3%) at least two falls. In univariate analysis, recurrent fallers were more likely than nonfallers and single fallers to fail the TUG (14% vs 7% and 7%) and FTSS (55% vs 35% and 38%) tests. Eighteen percent of the single fallers and 16% of the recurrent fallers failed the OLB test, versus 9% of nonfallers. A multivariable analysis was conducted using a Cox proportional hazard regression model with time-independent covariates. Of the three tests, only an FTSS time longer than 15 seconds was independently associated with risk of recurrent falls, after adjustment for four significant covariates (history of fall, sex, number of medications, and living alone) (risk ratio=1.74, 95% confidence interval=1.24–2.45, P<.001). The optimal cutoff time for performing the FTSS test in predicting recurrent fallers was 15 seconds (sensitivity 55%, specificity 65%), which corresponds to the mean value of the time required to conduct this test in the entire population. The Kaplan-Meier analysis illustrates the risk of recurrent falls during the follow-up period in subjects with FTSS times longer than 15 seconds and 15 seconds or less (Figure 1). Kaplan-Meier curves for prediction of recurrent falls for subjects who took longer than 15 seconds (gray line) and 15 seconds or less (black line) to complete the Five Times Sit-to-Stand (FTSS). The FTSS has a significant predictive value for recurrent falls in a population of community-living elderly subjects aged 65 and older independently of the other main risk factors, including history of falls, living alone, female sex, and number of medications. Subjects who needed more than 15 seconds to complete the test had a 74% greater risk of recurrent falls than those who took less time. Two prospective studies have shown that inability to rise from chair is associated with risk of falls in older persons.6,7 The current study shows, in a larger population than in previous studies, that the threshold of 15 seconds for the FTSS test has been useful for the detection of elderly subjects at higher risk of recurrent falls independent of the other main risk factors for falls. The slower FTSS test time observed in recurrent fallers could reflect postural balance disorders or muscular weakness of the lower limbs in these individuals.5,8 The current study did not find a significant predictive value for recurrent falls for the TUG and OLB tests. A previous study3 demonstrated that impaired performance on the OLB test was the only significant independent predictor of injurious falls but not of all falls. In previous prospective studies, the TUG test did not predict risk of falls in a group of older healthy adults.9,10 The FTSS is easy to score and quick to administer, requires little space, and needs no special equipment. Consequently clinicians could easily use it to identify people at high risk of recurrent falls and who are appropriate subjects for preventive measures. The authors thank the Centre de Médecine Préventive, Vandoeuvre-lés-Nancy, France. Sophie Rushton-Smith, PhD, provided editorial assistance in the preparation of this manuscript. Conflict of Interest: The editor in chief has reviewed the conflict of interest checklist provided by the authors and has determined that the authors have no financial or any other kind of personal conflicts with this letter. This study was supported by grants from the Communauté Urbaine du Grand Nancy. Author Contributions: Severine Buatois: study concept and design, subject recruitment, analysis and interpretation of data, writing the manuscript. Darko Miljkovic: study concept and design, acquisition of data, interpretation of data, writing the manuscript. Patrick Manckoundia: study concept and design, contribution in manuscript preparation. Rene Gueguen: acquisition of data, analysis and interpretation of data, contribution in manuscript preparation. Patrick Miget: study concept and design, subject recruitment, realization of the clinical balance tests, interpretation of data. Guy Vançon: interpretation of data, contribution in manuscript preparation. Philippe Perrin: study concept and design, interpretation of data, contribution in manuscript preparation. Athanase Benetos: chief investigator, study concept and design, analysis and interpretation of data, writing the manuscript. Sponsor's Role:“Communauté Urbaine du Grand Nancy” had no role in the design, methods, subject recruitment, data collection, analysis, or preparation of this manuscript.