Department of Geriatrics, Tianjin Medical University General Hospital; Tianjin Geriatrics Institute, Tianjin, China.
Department of Ultrasound, Tianjin People's Hospital, Tianjin, China.
Psychogeriatrics. 2020 Jan;20(1):35-43. doi: 10.1111/psyg.12452. Epub 2019 Apr 5.
Obesity contributes to the development of mild cognitive impairment, but the potential role of normal weight obesity in this disease has not been explored in humans. The aim of the study was to reveal the relationship between normal weight obesity and mild cognitive impairment in elderly individuals.
This study consisted of 360 patients with amnestic mild cognitive impairment and 360 cognitively normal controls. Normal weight obesity was defined as having metabolic syndrome but a normal weight. Metabolic health meant having no metabolic syndrome. Reverse transcription quantitative real-time polymerase chain reaction was adopted to measure the messenger RNA expression of four cognitive-related genes (amyloid precursor protein, cyclic adenosine monophosphate-responsive element-binding protein 1, sortilin-related receptor 1, and synapsin I) in peripheral blood mononuclear cells.
Normal weight obesity was related to a higher risk of amnestic mild cognitive impairment (odds ratio = 3.14, 95% confidence interval: 2.13-4.60). In the patients, the expression of each gene in the peripheral blood mononuclear cells was linearly related to Mini-Mental State Examination and Montreal Cognitive Assessment scores (P < 0.05). The expression of these genes in the patients with metabolic health deviated from the normal levels found in the controls (P < 0.05), and the deviations were more significant in the patients with normal weight obesity (P < 0.05).
Normal weight obesity may be a potential risk factor for amnestic mild cognitive impairment in elderly. This relationship was reflected in the abnormal expression of several cognitive-related genes in peripheral blood mononuclear cells.
肥胖会导致轻度认知障碍的发生，但正常体重肥胖在该疾病中的潜在作用尚未在人类中得到探索。本研究旨在揭示老年人正常体重肥胖与轻度认知障碍之间的关系。
本研究纳入了 360 例遗忘型轻度认知障碍患者和 360 例认知正常对照者。正常体重肥胖定义为患有代谢综合征但体重正常。代谢健康是指没有代谢综合征。采用逆转录定量实时聚合酶链反应测定外周血单个核细胞中 4 种认知相关基因（淀粉样前体蛋白、环磷酸腺苷反应元件结合蛋白 1、分选连接受体 1 和突触素 I）的信使 RNA 表达。
正常体重肥胖与遗忘型轻度认知障碍的发病风险增加相关（比值比=3.14，95%置信区间：2.13-4.60）。在患者中，外周血单个核细胞中每个基因的表达均与简易精神状态检查和蒙特利尔认知评估评分呈线性相关（P<0.05）。这些基因在代谢健康患者中的表达偏离了对照组的正常水平（P<0.05），在正常体重肥胖患者中的偏离更为显著（P<0.05）。
正常体重肥胖可能是老年人遗忘型轻度认知障碍的潜在危险因素。这种关系反映在外周血单个核细胞中几个认知相关基因的异常表达上。
