Knight Alissa, Bryan Janet, Wilson Carlene, Hodgson Jonathan, Murphy Karen
School of Psychology, Social Work and Social Policy, Alliance for Research in Exercise, Nutrition and Activity (ARENA), Bonython Jubilee Building, City East Campus, Frome Road, Adelaide, SA, 5000, Australia.
School of Medicine, The Flinders University of South Australia, Health Sciences Building, Sturt Rd, Bedford Park, Adelaide, SA, 5042, Australia.
BMC Geriatr. 2015 Apr 28;15:55. doi: 10.1186/s12877-015-0054-8.
The incidence of age-related cognitive decline is rising considerably around the world. There is evidence from a number of recent cross-sectional and prospective studies indicating positive associations between the Mediterranean dietary pattern (MedDiet) and improved cognitive outcomes among the elderly including, reduced age-related cognitive decline and enhanced age-related cognitive performance. However, to date no study has validated these associations in healthy older adult populations (≥65 years and above) with randomised evidence. The main aim of the present study is to provide justified evidence regarding the efficacy of a MedDiet approach to safely reduce the onset of cognitive decline, and promote optimal cognitive performance among healthy older adults using rigorous, randomised intervention methodology.
METHODS/DESIGN: MedLey is a 6-month, randomised controlled 2-cohort parallel group intervention trial, with initial assessment at baseline and repeated every three months. A sample of 166 healthy Australian men and women aged 65 years and above, with normal cognitive function and proficient in English language were recruited from metropolitan Adelaide, South Australia for the study. Participants randomly allocated to the experimental group are required to maintain an intervention dietary pattern based from the traditional Cretan MedDiet (i.e. vegetables, fruits, olive oil, legumes, fish, whole grain cereals, nuts and seeds and low consumption of processed foods, dairy products, red meat and vegetable oils) for six months, while those participants allocated to the control group are asked to maintain their customary lifestyle and diet. The primary outcome of interest is the quantitative difference in age-related cognitive performance, as measured by latent variables (cognitive constructs) sensitive to normal ageing and diet (i.e. speed of processing, memory, attention, executive functions, visual spatial and visuomotor ability). Secondary outcomes include change in biomarkers of inflammation, oxidative stress, lipid metabolism, glucose, insulin, blood flow velocity, and psychological well-being factors (i.e. stress, sleep, anxiety, depression).
To our knowledge this will be one of the first randomised clinical trials worldwide to provide evidence for the cause-effect relationship between the MedDiet and age-related cognitive function in a healthy older adult population (≥65 years and over).
Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12613000602729.
在全球范围内，与年龄相关的认知能力下降的发生率正在大幅上升。最近的一些横断面研究和前瞻性研究表明，地中海饮食模式（MedDiet）与老年人认知结果改善之间存在正相关，包括减少与年龄相关的认知能力下降以及提高与年龄相关的认知表现。然而，迄今为止，尚无研究在健康的老年人群（65岁及以上）中通过随机证据验证这些关联。本研究的主要目的是使用严格的随机干预方法，提供合理证据证明MedDiet方法在安全降低认知能力下降发生率以及促进健康老年人最佳认知表现方面的有效性。
方法/设计：MedLey是一项为期6个月的随机对照双队列平行组干预试验，在基线时进行初始评估，并每三个月重复一次。从南澳大利亚州阿德莱德市招募了166名年龄在65岁及以上、认知功能正常且精通英语的健康澳大利亚男性和女性作为研究样本。随机分配到实验组的参与者需要在六个月内保持基于传统克里特岛MedDiet的干预饮食模式（即蔬菜、水果、橄榄油、豆类、鱼类、全谷物、坚果和种子，以及少量食用加工食品、乳制品、红肉和植物油），而分配到对照组的参与者则被要求保持其习惯的生活方式和饮食。感兴趣的主要结果是与年龄相关的认知表现的定量差异，通过对正常衰老和饮食敏感的潜在变量（认知结构）来衡量（即处理速度、记忆力、注意力、执行功能、视觉空间和视觉运动能力）。次要结果包括炎症、氧化应激、脂质代谢、葡萄糖、胰岛素、血流速度和心理健康因素（即压力、睡眠、焦虑、抑郁）的生物标志物变化。
据我们所知，这将是全球首批为健康老年人群（65岁及以上）中MedDiet与年龄相关认知功能之间的因果关系提供证据的随机临床试验之一。
澳大利亚和新西兰临床试验注册中心（ANZCTR）：ACTRN12613000602729。
