Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland.
College of Nursing and Health Professions, Drexel University, Philadelphia, Pennsylvania.
J Am Geriatr Soc. 2019 Jan;67(1):87-92. doi: 10.1111/jgs.15609. Epub 2018 Oct 26.
To determine whether visual field (VF) damage or other factors confer a similar risk of falling when falls are ascertained as a rate over time (falls/year) as when ascertained over activity (falls/step).
Prospective, observational cohort study.
Clinic-based recruitment with real-world monitoring of falls and physical activity.
Individuals with glaucoma or suspected glaucoma (N=230).
Participants recorded falls using daily calendars, with injuries identified in a follow-up questionnaire. Annual 1-week accelerometer trials were used to estimate steps. VF results from both eyes were merged to determine integrated VF sensitivity, with lower sensitivity indicating greater VF damage. Other potential risk factors for falls (age, sex, race, comorbid illness, polypharmacy) were determined using questionnaires.
The cumulative probability of falls was 45.2% at 12 months and 61.6% at 24 months; cumulative probability of injurious falls was 23.3% at 12 months and 40.0% at 24 months. Greater VF damage was associated with higher rates of falls/steps (incident rate ratio = 1.40/5 dB decrement in sensitivity; p = .004) but not with more falls/year (incident rate ratio = 1.25/5 dB decrement in sensitivity; p = .07). Several additional variables (older age, female sex, more comorbid disease) were also associated with a higher rate of falls/step (p < .02 for all) but not with falls/year (p > 0.10). Black participants had fewer falls/year than whites (p = .002) but did not differ in falls/step (p = .07). Similar results were obtained when injurious falls were analyzed.
Risk factors associated with frequent falls when walking (falls/step) are not properly identified when analyzing falls as a rate over time (falls/year). Given the clinical importance of preventing falls while preserving physical activity, falls assessment integrated with activity measurement is recommended when determining whether a risk factor is associated with falls. J Am Geriatr Soc 67:87-92, 2019.
确定视野（VF）损伤或其他因素在通过时间（每年的跌倒次数）确定跌倒率与通过活动（每步的跌倒次数）确定跌倒率时，是否具有相似的跌倒风险。
前瞻性观察队列研究。
以诊所为基础的招募，同时对跌倒和身体活动进行真实世界的监测。
青光眼或疑似青光眼患者（N=230）。
参与者使用每日日历记录跌倒情况，并在后续问卷中确定受伤情况。每年进行 1 周的加速度计试验，以估计步数。合并双眼的 VF 结果以确定综合 VF 灵敏度，灵敏度越低表示 VF 损伤越大。使用问卷确定其他跌倒的潜在危险因素（年龄、性别、种族、合并症、多种药物治疗）。
12 个月时累积跌倒概率为 45.2%，24 个月时累积跌倒概率为 61.6%；12 个月时累积受伤跌倒概率为 23.3%，24 个月时累积受伤跌倒概率为 40.0%。VF 损伤越严重，跌倒/步数发生率越高（发生率比=每 5 dB 灵敏度下降 1.40；p=0.004），但每年的跌倒次数没有增加（发生率比=每 5 dB 灵敏度下降 1.25；p=0.07）。其他几个变量（年龄较大、女性、更多合并症）也与更高的跌倒/步数发生率相关（所有变量 p<0.02），但与每年的跌倒次数无关（p>0.10）。黑人参与者每年的跌倒次数少于白人（p=0.002），但在跌倒/步数方面没有差异（p=0.07）。当分析受伤跌倒时，也得到了类似的结果。
与行走时频繁跌倒相关的危险因素（跌倒/步数），在分析随时间变化的跌倒率（每年的跌倒次数）时并不能正确识别。鉴于预防跌倒和保持身体活动的重要性，在确定危险因素与跌倒是否相关时，建议将跌倒评估与活动测量相结合。美国老年医学会杂志 67:87-92, 2019.
