Guo Chun-Yan, Sun Zhen, Tan Chen-Chen, Tan Lan, Xu Wei
Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China.
Front Aging Neurosci. 2022 May 11;14:855553. doi: 10.3389/fnagi.2022.855553. eCollection 2022.
Frailty is a multidimensional syndrome that increases an individual's vulnerability for developing adverse health outcomes, which include dementia. It might serve as a promising target for dementia prevention. However, there are currently no studies summarizing the association between multi-concept frailty and the risk of cognitive disorders. This study aims to summarize the evidence of associations between multi-concept frailty and cognitive disorders based on longitudinal studies.
Scopus, The Cochrane Library, PsycINFO, CINAHL, PubMed, and EMBASE databases were searched from inception to January 2, 2022. Longitudinal studies, which explored the association of frailty with incident risk of cognitive decline or dementia, were included. The multivariable-adjusted effect estimates were pooled by random-effects models. The evidence credibility was depicted according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) method.
A total of 30 longitudinal studies were included. Four types of frailty concepts were involved, including physical, cognitive, social, and biopsychosocial frailty. The meta-analysis comprised 20 studies of 252,571 older adults (mean age: 64.1-80.4 years), among whom 7,388 participants developed cognitive decline or dementia. Physical frailty was associated with higher risk of developing cognitive disorders [pooled relative risk (pRR) = 1.52, 95% confidence interval (CI): 1.28-1.80, = 21.2%, pRR = 1.62 for cognitive decline, 95% CI: 1.07-2.45, = 40.2%, pRR = 1.37 for all-cause dementia (ACD), 95% CI: 1.13-1.66, = 0.0%]. Cognitive frailty (pRR = 2.90, 95% CI: 1.28-6.55, = 78.1%) and pre-frailty (pRR = 4.24, 95% CI: 2.74-6.56, = 30.2%) were linked to higher risk of ACD. Biopsychosocial frailty could predict a 41% (pRR = 1.41, 95% CI: 1.17-1.71) elevated risk of cognitive decline or dementia [pRR = 1.53 (95% CI: 1.19-1.96) for ACD and 1.11 (95% CI: 1.05-1.17) for Alzheimer's disease (AD)]. In the systematic review, social frailty was associated with a 53% higher risk of AD. Preventing frailty could avoid a maximum of 9.9% cognitive disorders globally. The overall evidence strength is rated as low-to-moderate. Inconsistency and imprecision are major sources of bias.
Frailty in late life is a promising risk factor for cognitive disorders. Frail elderly should be monitored for their cognitive dynamics and initiate early prevention of dementia.
www.ClinicalTrials.gov, identifier CRD4202127 3434.
衰弱是一种多维度综合征，会增加个体发生不良健康结局（包括痴呆症）的易感性。它可能是痴呆症预防的一个有前景的目标。然而，目前尚无研究总结多概念衰弱与认知障碍风险之间的关联。本研究旨在基于纵向研究总结多概念衰弱与认知障碍之间关联的证据。
检索Scopus、Cochrane图书馆、PsycINFO、CINAHL、PubMed和EMBASE数据库，检索时间从建库至2022年1月2日。纳入探讨衰弱与认知衰退或痴呆症发病风险之间关联的纵向研究。采用随机效应模型汇总多变量调整后的效应估计值。根据推荐分级评估、制定和评价（GRADE）方法描述证据可信度。
共纳入30项纵向研究。涉及四种衰弱概念，包括身体衰弱、认知衰弱、社会衰弱和生物心理社会衰弱。荟萃分析纳入了20项针对252,571名老年人（平均年龄：64.1 - 80.4岁）的研究，其中7388名参与者出现了认知衰退或痴呆症。身体衰弱与发生认知障碍的较高风险相关[合并相对风险（pRR）= 1.52，95%置信区间（CI）：1.28 - 1.80，I² = 21.2%；认知衰退的pRR = 1.62，95% CI：1.07 - 2.45，I² = 40.2%；全因痴呆症（ACD）的pRR = 1.37，95% CI：1.13 - 1.66，I² = 0.0%]。认知衰弱（pRR = 2.90，95% CI：1.28 - 6.55，I² = 78.1%）和衰弱前期（pRR = 4.24，95% CI：2.74 - 6.56，I² = 30.2%）与ACD的较高风险相关。生物心理社会衰弱可预测认知衰退或痴呆症风险升高41%（pRR = 1.41，95% CI：1.17 - 1.71）[ACD的pRR = 1.53（95% CI：1.19 - 1.96），阿尔茨海默病（AD）的pRR = 1.11（95% CI：1.05 - 1.17）]。在系统评价中，社会衰弱与AD风险高53%相关。全球范围内，预防衰弱最多可避免9.9%的认知障碍。总体证据强度被评为低到中等。不一致性和不精确性是主要的偏倚来源。
晚年衰弱是认知障碍的一个有前景的风险因素。应对体弱老年人的认知动态进行监测，并尽早开展痴呆症预防。
