Brach Jennifer S, Solomon Cam, Naydeck Barbara L, Sutton-Tyrrell Kim, Enright Paul L, Jenny Nancy Swords, Chaves Paulo M, Newman Anne B
Department of Physical Therapy, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
J Am Geriatr Soc. 2008 Jun;56(6):1037-44. doi: 10.1111/j.1532-5415.2008.01719.x. Epub 2008 Apr 1.
To evaluate the risk of incident physical disability and the decline in gait speed over a 6-year follow-up associated with a low ankle-arm index (AAI) in older adults.
Observational cohort study.
Forsyth County, North Carolina; Sacramento County, California; Washington County, Maryland; and Allegheny County, Pennsylvania.
Four thousand seven hundred five older adults, 58% women and 17.6% black, participating in the Cardiovascular Health Study.
AAI was measured in 1992/93 (baseline). Self-reported mobility, activity of daily living (ADL), and instrumental activity of daily living (IADL) disability and gait speed were recorded at baseline and at 1-year intervals over 6 years of follow-up. Mobility disability was defined as any difficulty walking half a mile and ADL and IADL disability was defined as any difficulty with 11 specific ADL and IADL tasks. Individuals with mobility, ADL, or IADL disability at baseline were excluded from the respective incident disability analyses.
Lower baseline AAI values were associated with increased risk of mobility disability and ADL/IADL disability. Clinical cardiovascular disease (CVD), diabetes mellitus, and interim CVD events partially explained these associations for mobility disability and clinical CVD and diabetes mellitus partially explained these associations for ADL and IADL disability. Individuals with an AAI less than 0.9 had on average a mean decrease in gait speed of 0.02 m/s per year, or a decline of 0.12 m/s over the 6-year follow-up. Prevalent CVD partly explained this decrease but interim CVD events did not further attenuate it.
Low AAI serves as marker of future disability risk. Reduction of disability risk in patients with a low AAI should consider cardiovascular comorbidity and the prevention of additional disabling CVD events.
评估老年人中低踝臂指数（AAI）与6年随访期间发生身体残疾及步态速度下降的风险。
观察性队列研究。
北卡罗来纳州福赛斯县；加利福尼亚州萨克拉门托县；马里兰州华盛顿县；宾夕法尼亚州阿勒格尼县。
4705名老年人，其中58%为女性，17.6%为黑人，参与心血管健康研究。
1992/93年（基线）测量AAI。在基线以及6年随访期间每年记录自我报告的行动能力、日常生活活动（ADL）、工具性日常生活活动（IADL）残疾情况及步态速度。行动能力残疾定义为行走半英里有任何困难，ADL和IADL残疾定义为11项特定ADL和IADL任务中有任何困难。基线时存在行动能力、ADL或IADL残疾的个体被排除在各自的新发残疾分析之外。
较低的基线AAI值与行动能力残疾及ADL/IADL残疾风险增加相关。临床心血管疾病（CVD）、糖尿病和CVD中期事件部分解释了这些与行动能力残疾的关联，临床CVD和糖尿病部分解释了这些与ADL和IADL残疾的关联。AAI小于0.9的个体平均每年步态速度平均下降0.02 m/s，在6年随访期间下降0.12 m/s。普遍存在的CVD部分解释了这种下降，但CVD中期事件并未进一步减弱这种下降。
低AAI可作为未来残疾风险的标志物。降低AAI低的患者的残疾风险应考虑心血管合并症及预防额外的致残性CVD事件。
