van der Zwaluw Nikita L, van de Rest Ondine, Tieland Michael, Adam Jos J, Hiddink Gert Jan, van Loon Luc J C, de Groot Lisette C P G M
Division of Human Nutrition, Wageningen University, P.O. Box 8129, 6700 EV, Wageningen, The Netherlands,
Eur J Nutr. 2014 Apr;53(3):803-12. doi: 10.1007/s00394-013-0584-9. Epub 2013 Sep 18.
Maintenance of cognitive abilities is important for elderly to stay independent. With the aging of the population, the call for modifiable factors is emerging. Dietary protein might improve cognitive performance; however, this has hardly been studied. Therefore, we studied the impact of 24-week dietary protein supplementation on cognitive performance in pre-frail and frail elderly people.
Pre-frail and frail elderly subjects, according to the Fried criteria, randomly received a protein drink containing 15 g protein or a placebo drink twice a day. Cognitive performance was measured at baseline and after 24 weeks by means of a sensitive neuropsychological test battery. In addition, reaction time was assessed after both 12 and 24 weeks of intervention. Domain scores were calculated for the domains episodic memory, attention and working memory, information processing speed, and executive functioning. Analyses of covariance were used to determine differences between groups. Linear mixed models were used to determine differences in reaction time over time and per treatment.
In total, 65 subjects (79 ± 8 years) with a median Mini-Mental State Examination score of 28 (interquartile range 26-30) were included. Reaction time improved more in the protein group (68 ms) than in the placebo group (18 ms, P = 0.03). Dietary protein had no significant effect on any of the cognitive domain scores.
Protein supplementation might improve reaction time performance in pre-frail and frail elderly, but did not improve other cognitive functions.
维持认知能力对老年人保持独立很重要。随着人口老龄化，对可改变因素的需求日益凸显。膳食蛋白质可能会改善认知表现；然而，这方面的研究很少。因此，我们研究了为期24周的膳食蛋白质补充对虚弱前期和虚弱老年人认知表现的影响。
根据弗里德标准，虚弱前期和虚弱的老年受试者随机每天两次接受含15克蛋白质的蛋白饮料或安慰剂饮料。在基线时和24周后通过一套敏感的神经心理学测试来测量认知表现。此外，在干预12周和24周后评估反应时间。计算情景记忆、注意力和工作记忆、信息处理速度以及执行功能等领域的得分。采用协方差分析来确定组间差异。使用线性混合模型来确定不同时间和不同治疗方式下反应时间的差异。
总共纳入了65名受试者（79±8岁），简易精神状态检查表中位数得分为28（四分位间距26 - 30）。蛋白组的反应时间改善（68毫秒）比安慰剂组（18毫秒）更多（P = 0.03）。膳食蛋白质对任何认知领域得分均无显著影响。
补充蛋白质可能会改善虚弱前期和虚弱老年人的反应时间表现，但不会改善其他认知功能。
