University of L'Aquila, Department of Life, Health, and Environmental Sciences, Viale S Salvatore, Delta 6 Medicina, 67100 Coppito, L'Aquila, Italy.
Hypertension. 2012 Sep;60(3):794-801. doi: 10.1161/HYPERTENSIONAHA.112.193060. Epub 2012 Aug 14.
Flavanol consumption is favorably associated with cognitive function. We tested the hypothesis that dietary flavanols might improve cognitive function in subjects with mild cognitive impairment. We conducted a double-blind, parallel arm study in 90 elderly individuals with mild cognitive impairment randomized to consume once daily for 8 weeks a drink containing ≈990 mg (high flavanols), ≈520 mg (intermediate flavanols), or ≈45 mg (low flavanols) of cocoa flavanols per day. Cognitive function was assessed by Mini Mental State Examination, Trail Making Test A and B, and verbal fluency test. At the end of the follow-up period, Mini Mental State Examination was similar in the 3 treatment groups (P=0.13). The time required to complete Trail Making Test A and Trail Making Test B was significantly (P<0.05) lower in subjects assigned to high flavanols (38.10±10.94 and 104.10±28.73 seconds, respectively) and intermediate flavanols (40.20±11.35 and 115.97±28.35 seconds, respectively) in comparison with those assigned to low flavanols (52.60±17.97 and 139.23±43.02 seconds, respectively). Similarly, verbal fluency test score was significantly (P<0.05) better in subjects assigned to high flavanols in comparison with those assigned to low flavanols (27.50±6.75 versus 22.30±8.09 words per 60 seconds). Insulin resistance, blood pressure, and lipid peroxidation also decreased among subjects in the high-flavanol and intermediate-flavanol groups. Changes of insulin resistance explained ≈40% of composite z score variability through the study period (partial r(2)=0.4013; P<0.0001). To the best of our knowledge, this is the first dietary intervention study demonstrating that the regular consumption of cocoa flavanols might be effective in improving cognitive function in elderly subjects with mild cognitive impairment. This effect appears mediated in part by an improvement in insulin sensitivity.
类黄酮的摄入与认知功能呈正相关。我们假设，饮食中的类黄酮可能会改善轻度认知障碍患者的认知功能。我们进行了一项双盲、平行分组研究，纳入 90 名老年轻度认知障碍患者，随机分为 3 组，每天分别摄入含有约 990mg（高类黄酮组）、520mg（中类黄酮组）或 45mg（低类黄酮组）可可类黄酮的饮料，持续 8 周。采用简易精神状态检查量表、连线测试 A 和 B、词语流畅性测试评估认知功能。随访结束时，3 组间简易精神状态检查量表评分无显著差异（P=0.13）。高类黄酮组和中类黄酮组完成连线测试 A 和 B 的时间明显短于低类黄酮组（分别为 38.10±10.94 和 104.10±28.73 秒、40.20±11.35 和 115.97±28.35 秒）。同样，高类黄酮组词语流畅性测试评分也显著高于低类黄酮组（27.50±6.75 比 22.30±8.09 个词/60 秒）。高类黄酮组和中类黄酮组的胰岛素抵抗、血压和脂质过氧化也有所下降。在研究期间，胰岛素抵抗的变化解释了复合 z 评分变化的约 40%（部分 r(2)=0.4013；P<0.0001）。据我们所知，这是第一项表明定期摄入可可类黄酮可能有效改善老年轻度认知障碍患者认知功能的饮食干预研究。这种作用部分通过改善胰岛素敏感性介导。
