Volkow Nora D, Wang Gene-Jack, Telang Frank, Fowler Joanna S, Goldstein Rita Z, Alia-Klein Nelly, Logan Jean, Wong Christopher, Thanos Panayotis K, Ma Yemine, Pradhan Kith
National Institute on Drug Abuse, Bethesda, Maryland, USA.
Obesity (Silver Spring). 2009 Jan;17(1):60-5. doi: 10.1038/oby.2008.469. Epub 2008 Oct 23.
Obesity has been associated with a higher risk for impaired cognitive function, which most likely reflects associated medical complications (i.e., cerebrovascular pathology). However, there is also evidence that in healthy individuals excess weight may adversely affect cognition (executive function, attention, and memory). Here, we measured regional brain glucose metabolism (using positron emission tomography (PET) and 2-deoxy-2[(18)F]fluoro-D-glucose (FDG)) to assess the relationship between BMI and brain metabolism (marker of brain function) in 21 healthy controls (BMI range 19-37 kg/m(2)) studied during baseline (no stimulation) and during cognitive stimulation (numerical calculations). Statistical parametric mapping (SPM) revealed a significant negative correlation between BMI and metabolic activity in prefrontal cortex (Brodmann areas 8, 9, 10, 11, 44) and cingulate gyrus (Brodmann area 32) but not in other regions. Moreover, baseline metabolism in these prefrontal regions was positively associated with performance on tests of memory (California Verbal Learning Test) and executive function (Stroop Interference and Symbol Digit Modality tests). In contrast, the regional brain changes during cognitive stimulation were not associated with BMI nor with neuropsychological performance. The observed association between higher BMI and lower baseline prefrontal metabolism may underlie the impaired performance reported in healthy obese individuals on some cognitive tests of executive function. On the other hand, the lack of an association between BMI and brain metabolic activation during cognitive stimulation indicates that BMI does not influence brain glucose utilization during cognitive performance. These results further highlight the urgency to institute public health interventions to prevent obesity.
肥胖与认知功能受损风险较高相关，这很可能反映了相关的医学并发症（即脑血管病变）。然而，也有证据表明，在健康个体中，超重可能会对认知（执行功能、注意力和记忆力）产生不利影响。在此，我们测量了局部脑葡萄糖代谢（使用正电子发射断层扫描（PET）和2-脱氧-2-[(18)F]氟-D-葡萄糖（FDG）），以评估21名健康对照者（BMI范围为19-37 kg/m(2)）在基线期（无刺激）和认知刺激（数字计算）期间BMI与脑代谢（脑功能标志物）之间的关系。统计参数映射（SPM）显示，BMI与前额叶皮质（布罗德曼区8、9、10、11、44）和扣带回（布罗德曼区32）的代谢活动呈显著负相关，但在其他区域则无此关联。此外，这些前额叶区域的基线代谢与记忆测试（加利福尼亚言语学习测试）和执行功能测试（斯特鲁普干扰测试和符号数字模式测试）的表现呈正相关。相比之下，认知刺激期间的局部脑变化与BMI和神经心理表现均无关联。观察到的较高BMI与较低的基线前额叶代谢之间的关联，可能是健康肥胖个体在某些执行功能认知测试中表现受损的基础。另一方面，BMI与认知刺激期间脑代谢激活缺乏关联，表明BMI在认知表现期间不影响脑葡萄糖利用。这些结果进一步凸显了开展公共卫生干预措施以预防肥胖的紧迫性。
