Department of Musculoskeletal Biology, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK; Society of Meta-research and Biomedical Innovation, London, UK.
Society of Meta-research and Biomedical Innovation, London, UK; Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK.
Am J Med. 2022 Aug;135(8):e257-e262. doi: 10.1016/j.amjmed.2022.03.022. Epub 2022 Apr 1.
Aging is a global health challenge that is associated with a decline in cognitive function. In the United States, most older adults (≥50 years) do not meet the recommended daily fiber intake, although preliminary evidence suggests that dietary fiber consumption could elicit clinical benefits on cognitive function. We investigated the associations between dietary fiber intake and cognitive function in older adults.
We analyzed data from the US National Health and Nutrition Examination Survey (NHANES) between 2011 and 2014, with a study cohort of 1070 older adults (≥60 years). Cognitive function was assessed using the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Word Learning Test (WLT), Word Recall Test (WRT) and their Intrusion Word Count Tests (WLT-IC and WRT-IC), the Animal Fluency Test (AFT), and the Digit Symbol Substitution Test (DSST). Multiple linear regression and cubic spline analyses were employed to examine the association between dietary fiber intake and cognitive performance on a test-by-test basis, after covariates adjustment (ie, age, sex, race, socioeconomic status, educational level, medical history, body mass index, alcohol, and energy intake).
Participants had a mean age of 69.2 years and were primarily non-Hispanic white of middle-high socioeconomic status with a college degree at minimum. The mean dietary fiber intake was 17.3 g/d. The analysis showed that dietary fiber intake was positively associated with DSST (P = .031). No associations with CERAD WLT (P = .41), WRT (P = .68), WLT-IC (P = .07), and WRT-IC (P = .28), and AFT (P = .40) scores were observed. A plateau in DSST score was revealed at a dietary fiber intake of 34 g/d.
Higher dietary fiber intake is associated with improved specific components of cognitive function in older adults aged 60 years and older. Public health interventions that target a recommended dietary fiber intake may provide a promising strategy to combat cognitive decline in high-risk groups of older adults.
衰老作为一个全球性的健康挑战，与认知功能下降有关。在美国，大多数老年人（≥50 岁）的膳食纤维摄入量未达到推荐量，尽管初步证据表明膳食纤维的摄入可能对认知功能有临床益处。我们调查了老年人膳食纤维摄入量与认知功能之间的关系。
我们分析了 2011 年至 2014 年期间美国国家健康和营养检查调查（NHANES）的数据，研究队列包括 1070 名老年人（≥60 岁）。认知功能使用认知障碍症联合会阿尔茨海默病评估量表（CERAD）单词学习测试（WLT）、单词回忆测试（WRT）及其插入单词计数测试（WLT-IC 和 WRT-IC）、动物流畅性测试（AFT）和数字符号替换测试（DSST）进行评估。采用多元线性回归和三次样条分析，在调整协变量（年龄、性别、种族、社会经济地位、教育程度、病史、体重指数、酒精和能量摄入）后，按测试逐一检查膳食纤维摄入量与认知表现之间的关系。
参与者的平均年龄为 69.2 岁，主要是非西班牙裔白人，社会经济地位处于中高水平，至少拥有大学学历。平均膳食纤维摄入量为 17.3 克/天。分析表明，膳食纤维摄入量与 DSST 呈正相关（P=0.031）。与 CERAD WLT（P=0.41）、WRT（P=0.68）、WLT-IC（P=0.07）和 WRT-IC（P=0.28）以及 AFT（P=0.40）得分均无关联。在膳食纤维摄入量为 34 克/天左右时，DSST 分数出现平台期。
较高的膳食纤维摄入量与 60 岁及以上老年人认知功能的特定成分改善有关。针对推荐膳食纤维摄入量的公共卫生干预措施可能是针对高风险老年人群体认知能力下降的一种有前景的策略。
