1 Department of Medicine, College of Physicians & Surgeons.
2 Department of Medicine, University of California-San Francisco, San Francisco, California.
Ann Am Thorac Soc. 2017 Aug;14(8):1270-1279. doi: 10.1513/AnnalsATS.201612-1008OC.
The frail phenotype has gained popularity as a clinically relevant measure in adults with advanced lung disease and in critical illness survivors. Because respiratory disease and chronic illness can greatly limit physical activity, the measurement of participation in traditional leisure time activities as a frailty component may lead to substantial misclassification of frailty in pulmonary and critical care patients.
To test and validate substituting the Duke Activity Status Index (DASI), a simple 12-item questionnaire, for the Minnesota Leisure Time Physical Activity (MLTA) questionnaire, a detailed questionnaire covering 18 leisure time activities, as the measure of low activity in the Fried frailty phenotype (FFP) instrument.
In separate multicenter prospective cohort studies of adults with advanced lung disease who were candidates for lung transplant and older survivors of acute respiratory failure, we assessed the FFP using either the MLTA or the DASI. For both the DASI and MLTA, we evaluated content validity by testing floor effects and construct validity through comparisons with conceptually related factors. We tested the predictive validity of substituting the DASI for the MLTA in the FFP assessment using Cox models to estimate associations between the FFP and delisting/death before transplant in those with advanced lung disease and 6-month mortality in older intensive care unit (ICU) survivors.
Among 618 adults with advanced lung disease and 130 older ICU survivors, the MLTA had a substantially greater floor effect than the DASI (42% vs. 1%, and 49% vs. 12%, respectively). The DASI correlated more strongly with strength and function measures than did the MLTA in both cohorts. In models adjusting for age, sex, comorbidities, and illness severity, substitution of the DASI for the MLTA led to stronger associations of the FFP with delisting/death in lung transplant candidates (FFP-MLTA hazard ratio [HR], 1.42; 95% confidence interval [CI], 0.55-3.65; FFP-DASI HR, 2.99; 95% CI, 1.03-8.65) and with mortality in older ICU survivors (FFP-MLTA HR, 2.68; 95% CI, 0.62-11.6; FFP-DASI HR, 5.71; 95% CI, 1.34-24.3).
The DASI improves the construct and predictive validity of frailty assessment in adults with advanced lung disease or recent critical illness. This simple questionnaire should replace the more complex MLTA in assessing the frailty phenotype in these populations.
脆弱表型作为一种与临床相关的测量方法，在晚期肺部疾病患者和重症疾病幸存者中越来越受欢迎。由于呼吸疾病和慢性疾病会极大地限制体力活动，因此将传统休闲时间活动的参与作为脆弱性组成部分进行测量可能会导致对肺部和重症监护患者脆弱性的严重分类错误。
测试并验证用简单的 12 项问卷杜克活动状态指数（DASI）代替详细问卷明尼苏达州休闲时间体力活动（MLTA）问卷，作为 Fried 脆弱表型（FFP）工具中低活动的衡量标准。
在分别针对晚期肺部疾病患者（这些患者为肺移植候选者）和急性呼吸衰竭的老年幸存者的多中心前瞻性队列研究中，我们使用 MLTA 或 DASI 评估了 FFP。对于 DASI 和 MLTA，我们通过测试地板效应和通过与概念相关因素的比较来评估结构有效性。我们使用 Cox 模型测试了用 DASI 代替 MLTA 对 FFP 评估的预测有效性，以估计 FFP 与晚期肺部疾病患者的除名/死亡前和老年重症监护病房（ICU）幸存者 6 个月死亡率之间的关联。
在 618 名晚期肺部疾病患者和 130 名老年 ICU 幸存者中，MLTA 的地板效应明显大于 DASI（分别为 42%和 1%，49%和 12%）。在两个队列中，DASI 与力量和功能测量的相关性均强于 MLTA。在调整年龄、性别、合并症和疾病严重程度的模型中，用 DASI 代替 MLTA 与肺移植候选者的除名/死亡（FFP-MLTA 危险比 [HR]，1.42；95%置信区间 [CI]，0.55-3.65；FFP-DASI HR，2.99；95% CI，1.03-8.65）和老年 ICU 幸存者的死亡率（FFP-MLTA HR，2.68；95% CI，0.62-11.6；FFP-DASI HR，5.71；95% CI，1.34-24.3）之间的关联更强。
DASI 提高了在晚期肺部疾病或近期重症疾病患者中进行脆弱性评估的结构和预测有效性。在这些人群中，这种简单的问卷应该替代更复杂的 MLTA 来评估脆弱表型。
