Geriatric Medicine-Memory Unit and Rare Disease Centre, University of Bari 'Aldo Moro', Bari, Italy.
Department of Basic Medicine, Neurodegenerative Disease Unit, Neuroscience, and Sense Organs, University of Bari Aldo Moro, Bari, Italy.
J Alzheimers Dis. 2018;64(s1):S229-S254. doi: 10.3233/JAD-179940.
The link diet-cognitive function/dementia has been largely investigated in observational studies; however, there was a lack of evidence from randomized clinical trials (RCTs) on the prevention of late-life cognitive disorders though dietary intervention in cognitively healthy older adults. In the present article, we systematically reviewed RCTs published in the last four years (2014-2017) exploring nutritional intervention efficacy in preventing the onset of late-life cognitive disorders and dementia in cognitively healthy subjects aged 60 years and older using different levels of investigation (i.e., dietary pattern changes/medical food/nutraceutical supplementation/multidomain approach and dietary macro- and micronutrient approaches) as well as possible underlying mechanisms of nutritional prevention. From the 35 included RCTs, there was moderate evidence that intervention through dietary pattern changes, medical food/nutraceutical supplementation, and multidomain approach improved specific cognitive domains or cognitive-related blood biomarkers. There was high evidence that protein supplementation improved specific cognitive domains or functional status in prefrail older adults without effect on cognitive function. For fatty acid supplementation, mainly long-chain polyunsaturated fatty acids, there was emerging evidence suggesting an impact of this approach in improving specific cognitive domains, magnetic resonance imaging (MRI) findings, and/or cognitive-related biomarkers also in selected subgroups of older subjects, although some results were conflicting. There was convincing evidence of an impact of non-flavonoid polyphenol and flavonoid supplementations in improving specific cognitive domains and/or MRI findings. Finally, there was only low evidence suggesting efficacy of intervention with homocysteine-related and antioxidant vitamins in improving cognitive functions, dementia incidence, or cognitive-related biomarkers in cognitively healthy older subjects.
饮食-认知功能/痴呆症之间的关联在观察性研究中得到了广泛研究；然而，在认知健康的老年人中通过饮食干预预防晚年认知障碍方面，缺乏来自随机临床试验 (RCT) 的证据。在本文中，我们系统地回顾了在过去四年（2014-2017 年）发表的 RCT，这些 RCT 探索了不同的研究水平（即饮食模式变化/医用食品/营养补充剂/多领域方法和饮食宏量和微量营养素方法）下营养干预对预防认知健康的老年人晚年认知障碍和痴呆的效果，以及营养预防的可能潜在机制。在纳入的 35 项 RCT 中，有中等证据表明，通过饮食模式改变、医用食品/营养补充剂和多领域方法进行干预可以改善特定的认知领域或与认知相关的血液生物标志物。有强有力的证据表明，蛋白质补充剂可以改善特定的认知领域或虚弱老年人的功能状态，但对认知功能没有影响。对于脂肪酸补充剂，主要是长链多不饱和脂肪酸，有新的证据表明，这种方法可以改善特定的认知领域、磁共振成像 (MRI) 结果和/或认知相关的生物标志物，也可以改善老年人群体中的特定亚组，尽管一些结果存在冲突。有令人信服的证据表明，非类黄酮多酚和类黄酮补充剂可以改善特定的认知领域和/或 MRI 结果。最后，只有低证据表明干预同型半胱氨酸相关和抗氧化维生素可以改善认知功能、痴呆发病率或认知健康老年人的认知相关生物标志物。
