Department of Medicine, Howard University, College of Medicine, Washington, DC, USA.
Lipids Health Dis. 2011 Jan 28;10:26. doi: 10.1186/1476-511X-10-26.
Low levels of both high density lipoprotein cholesterol (HDL) and cognitive function are associated with increased mortality risk. HDL plays an important role in brain metabolism. We test the hypotheses that the relative protective effect of high HDL level as related to mortality is greater in persons with impaired cognitive function than in others. Data were analyzed from a longitudinal mortality follow-up study of 4911 American men and women aged 60 years and over examined in 1988-1994 followed an average 8.5 yr. Measurements at baseline included HDL, a short index of cognitive function (SICF), socio-demographics, health status, and self-reported leisure-time physical activity. In proportional hazards regression analysis, no significant interaction of HDL with cognitive function was found (p = 0.08); there was a significant age-SICF interaction. After stratifying by age and adjusting for confounding by multiple variables, independent associations of HDL and SICF score with survival were strongest among the oldest persons. Consistent with its association with HDL, cognitive function and survival, controlling in addition for physical activity reduced the associations. In a nationwide cohort of older Americans, analyses demonstrated a lower risk of death independent of confounders among those high HDL and SICF scores, strongest among the oldest persons.
低水平的高密度脂蛋白胆固醇 (HDL) 和认知功能与死亡率风险增加有关。HDL 在大脑代谢中发挥着重要作用。我们检验了以下假设：与认知功能正常者相比，HDL 水平较高与死亡率相关的相对保护作用在认知功能受损者中更大。本研究的数据来自一项对 4911 名年龄在 60 岁及以上的美国男女进行的纵向死亡率随访研究，这些人于 1988-1994 年接受检查，平均随访 8.5 年。基线测量包括 HDL、认知功能简短指数 (SICF)、社会人口统计学、健康状况和自我报告的休闲时间体育活动。在比例风险回归分析中，未发现 HDL 与认知功能之间存在显著的相互作用（p = 0.08）；存在年龄-SICF 相互作用。按年龄分层并调整多个变量的混杂因素后，HDL 和 SICF 评分与生存的独立关联在最年长的人群中最强。与 HDL 和认知功能与生存相关一致，在控制了体育活动的情况下，认知功能降低了这些关联。在一项针对全美老年人群的队列研究中，分析表明，在那些 HDL 和 SICF 评分较高的人群中，独立于混杂因素，死亡风险较低，在最年长的人群中最强。
