In HIV medicine, the Veterans Aging Cohort Study (VACS) index is associated to some geriatric syndromes and has also been recently used as a proxy of frailty. However, using it as a proxy for the frailty phenotype may inadvertently interchange two different concepts. The purpose of this study was to evaluate to what extent the frailty phenotype may be explained by the index. Cross-sectional analysis included 393 participants with HIV aged 50 or older. Somers' delta (d) was calculated, and a multinomial logistic regression model was run to determine to what extent the VACS index scores explained the probability of being prefrail or frail. Mean age was 57.6 (standard deviation 6.5) years and 87.3% men. A weak, but positive association between the VACS 2.0 index score and the frailty phenotype was established (Somers' d = 0.120, p < .001). The multinomial logistic regression showed that prefrail and frail participants had higher probabilities for greater VACS index scores [OR = 1.05, 95% confidence intervals (CI) 1.01–1.09; p = .006 and OR = 1.17, 95% CI 1.09–1.26; p < .001, respectively]; however, VACS index only explained <12% of the variability observed in the frailty phenotype. High VACS index scores were associated with a greater probability of being frail; however, with a weak association. Thus, we should be cautious when using the VACS index as a general proxy of frailty, particularly for the frailty phenotype. However, the VACS index may be used as a means to identify persons who might benefit from further comprehensive geriatric assessment.

中文翻译：

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退伍军人老化队列研究指数和脆弱性：整体的一部分

在 HIV 医学中，退伍军人衰老队列研究 (VACS) 指数与一些老年综合症相关，最近也被用作虚弱指标。然而，将其用作虚弱表型的代理可能会无意中互换两个不同的概念。本研究的目的是评估该指数可以在多大程度上解释虚弱表型。横断面分析包括 393 名 50 岁或以上的 HIV 参与者。萨默斯三角洲 ( d) 进行计算，并运行多项逻辑回归模型以确定 VACS 指数得分在多大程度上解释了衰弱前或衰弱的概率。平均年龄为 57.6（标准差 6.5）岁，男性占 87.3%。在 VACS 2.0 指数评分和虚弱表型之间建立了微弱但正相关的关系（Somers' d  = 0.120，p  < .001）。多项逻辑回归表明，虚弱前和虚弱参与者获得更高 VACS 指数得分的概率更高 [OR = 1.05，95% 置信区间 (CI) 1.01–1.09；p  = .006 和 OR = 1.17，95% CI 1.09–1.26；p < .001，分别]；然而，VACS 指数只能解释 <12% 的虚弱表型变异性。高 VACS 指数得分与更大的虚弱概率相关；但是，关联性较弱。因此，在使用 VACS 指数作为虚弱的一般代理时，我们应该谨慎，特别是对于虚弱表型。然而，VACS 指数可用作识别可能受益于进一步综合老年评估的人的手段。