Yale University School of Medicine, Department of Internal Medicine, New Haven, CT, USA.
JAMA. 2010 Nov 3;304(17):1919-28. doi: 10.1001/jama.2010.1568.
Disability among older persons is a complex and highly dynamic process, with high rates of recovery and frequent transitions between states of disability. The role of intervening illnesses and injuries (ie, events) on these transitions is uncertain.
To evaluate the relationship between intervening events and transitions among states of no disability, mild disability, severe disability, and death and to determine the association of physical frailty with these transitions.
DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study conducted in greater New Haven, Connecticut, from March 1998 to December 2008 of 754 community-living persons aged 70 years or older who were nondisabled at baseline in 4 essential activities of daily living: bathing, dressing, walking, and transferring. Telephone interviews were completed monthly for more than 10 years to assess disability and ascertain exposure to intervening events, which included illnesses and injuries leading to either hospitalization or restricted activity. Physical frailty (defined as gait speed >10 seconds on the rapid gait test) was assessed every 18 months through 108 months.
Transitions between no disability, mild disability, and severe disability and 3 transitions from each of these states to death, evaluated each month.
Hospitalization was strongly associated with 8 of the 9 possible transitions, with increased multivariable hazard ratios (HRs) as high as 168 (95% confidence interval [CI], 118-239) for the transition from no disability to severe disability and decreased HRs as low as 0.41 (95% CI, 0.30-0.54) for the transition from mild disability to no disability. Restricted activity also increased the likelihood of transitioning from no disability to both mild and severe disability (HR, 2.59; 95% CI, 2.23-3.02; and HR, 8.03; 95% CI, 5.28-12.21), respectively, and from mild disability to severe disability (HR, 1.45; 95% CI, 1.14-1.84), but was not associated with recovery from mild or severe disability. For all 9 transitions, the presence of physical frailty accentuated the associations of the intervening events. For example, the absolute risk of transitioning from no disability to mild disability within 1 month after hospitalization for frail individuals was 34.9% (95% CI, 34.5%-35.3%) vs 4.9% (95% CI, 4.7%-5.1%) for nonfrail individuals. Among the possible reasons for hospitalization, fall-related injury conferred the highest likelihood of developing new or worsening disability.
Among older persons, particularly those who were physically frail, intervening illnesses and injuries greatly increased the likelihood of developing new or worsening disability. Only the most potent events, ie, those leading to hospitalization, reduced the likelihood of recovery from disability.
老年人的残疾是一个复杂且高度动态的过程，具有较高的康复率和频繁的残疾状态转变。介入性疾病和损伤（即事件）对这些转变的作用尚不确定。
评估介入性事件与无残疾、轻度残疾、重度残疾和死亡状态之间的转变关系，并确定身体虚弱与这些转变的关联。
设计、地点和参与者：这是一项前瞻性队列研究，于 1998 年 3 月至 2008 年 12 月在康涅狄格州纽黑文市进行，纳入了 754 名年龄在 70 岁或以上、基线时在 4 项日常生活活动中无残疾的社区居住者：洗澡、穿衣、行走和转移。每月进行电话访谈，持续 10 年以上，以评估残疾情况，并确定介入性事件的暴露情况，包括导致住院或活动受限的疾病和损伤。每 18 个月通过快速步态测试评估身体虚弱（定义为步态速度> 10 秒），持续 108 个月。
无残疾、轻度残疾和重度残疾之间的转变，以及从每种状态到死亡的 3 种转变，每月评估一次。
住院与 9 种可能转变中的 8 种有很强的关联，多变量危险比（HR）最高可达 168（95%置信区间[CI]，118-239），从无残疾转变为重度残疾，而 HR 最低可达 0.41（95%CI，0.30-0.54），从轻度残疾转变为无残疾。活动受限也增加了从无残疾向轻度和重度残疾转变的可能性（HR，2.59；95%CI，2.23-3.02；和 HR，8.03；95%CI，5.28-12.21），以及从轻度残疾向重度残疾转变的可能性（HR，1.45；95%CI，1.14-1.84），但与从轻度或重度残疾中康复无关。对于所有 9 种转变，身体虚弱的存在都加重了介入事件的关联。例如，对于虚弱的个体，在因疾病或损伤住院后 1 个月内从无残疾转变为轻度残疾的绝对风险为 34.9%（95%CI，34.5%-35.3%），而非虚弱的个体为 4.9%（95%CI，4.7%-5.1%）。在可能导致住院的原因中，与跌倒相关的损伤导致新的或加重残疾的可能性最高。
在老年人中，尤其是身体虚弱的老年人中，介入性疾病和损伤大大增加了发生新的或加重残疾的可能性。只有最严重的事件，即导致住院的事件，才会降低残疾康复的可能性。
