24-hour pattern of falls in hospitalized and long-term care institutionalized elderly persons: A systematic review of the published literature.

Falls are common among the elderly > 65 years of age and can result in both serious trauma and costly medical care. The epidemiology of falls in the elderly typically focuses on identifying contributory exogenous environmental and endogenous age-related physical, cognitive and other health status factors; however, one potentially important variable seldom considered is time of fall. We sought to determine if falls in hospitalized/institutionalized elderly persons exhibit 24 h and other temporal patterns, since knowledge of such could be useful in their prevention. We conducted a systematic review of the published literature to critically appraise and synthesize the methods and findings of previous reports addressing clock-time, day-of-week and month-of-year fall patterns of institutionalized elderly cohorts. Medline, SCOPUS, Ovid SP and Web of Knowledge were systematic assessed, entering search terms of "accidental fall", "circadian rhythm", "biological clocks", "circadian clocks", "activity cycles", "periodicity", and with databases accepting an age limiter, "age of 65+ years". Methodological quality was assessed by STROBE and CONSORT checklists, respectively, in observational and clinical studies. Publications were reviewed if meeting inclusion criteria of: (i) being an empirical study, (ii) adopting circadian and/or other period rhythmicity as a fall risk, and (iii) focusing on hospitalized/institutionalized falls in those ≥ 65 years of age; plus exclusion criteria of: (i) cohort < 65 years of age and (ii) reports as dissertations or editorials. The search retrieved 170 publications; however, only nine met all inclusion/exclusion criteria. Typically, past studies disregarded the temporal aspects of fall incidents; the few that did varied in quality, institutional setting, and patient type, i.e. medical diagnoses. Overall, findings suggest a single or double-peak 24 h pattern of fall incidence, with time of greatest incidence seemingly associated with circadian rhythm-dependent differences in the symptom intensity of dominating medical diagnoses (e.g. heart failure versus Alzheimer syndrome) among sample cohorts plus location (e.g. bathroom versus hallway) of occurrence. Future research is urgently required to define temporal patterns in falls and their etiology, e.g. relative to circadian and other rhythms in both the manifestation and intensity of medical conditions and adverse effects of medications according to scheduling, plus staff personnel number and work schedules as it affects patient oversight, and cyclic environmental conditions (e.g. light intensity exposure) to best design preventive measures