Objective: To examine the association of blood uric acid (UA) and cognitive impairment (CI) among oldest-old adults in China. Methods: Data was collected in 9 longevity areas of China from Healthy Aging and Biomarkers Cohort Study (HABCS) conducted during 2017-2018. Finally,1, 622 elderly aged 80 years and older with complete information on blood UA and cognitive function score were included in this study. Information on demographic characteristics, lifestyle, and health status were collected through questionnaire and physical examination. Venous blood samples of the participants were collected to test blood UA level. Cognitive impairment (CI) was assessed using the Chinese Mini-Mental State Examination (MMSE) according to personal educational level. Generalized Estimating Equations (GEE) model for binary data was used to analyze the association of blood UA and CI, and further compared the associations among different age and body mass index (BMI) groups. Results: Of the 1 622 oldest-old, the mean age was (92.2±8.1) years, 656 (40.4%) were male, the mean level of blood UA was (343.3±86.2) μmol/L, and 482 (29.7%) oldest-old had CI. Compared with the lowest quartile of UA, the risks of CI in the second, third and highest quartiles were gradually reduced, the corresponding ORs and 95%CI were 0.99 (0.71-1.33), 0.87 (0.68-0.94) and 0.69 (0.48-0.85), respectively; and the linear trend test was statistically significant (P<0.001). Subgroup analysis showed that the effects of higher UA associated with lower risk of CI were stronger in younger oldest-old (aged 80-89 years) and thinner group (BMI<24) (Pinteraction<0.05). Conclusions: Blood UA was negatively associated with the risk of having CI in the oldest-old among the nine longevity areas of China.
目的： 分析中国长寿地区80岁及以上人群血尿酸水平与认知功能受损的关联。 方法： 研究对象来自2017—2018年在我国9个长寿地区开展的“老年健康生物标志物队列研究”，共纳入1 622名血尿酸和认知功能得分数据完整的80岁及以上研究对象。通过问卷调查和体格检查，收集调查对象的人口学特征、生活方式及健康状况等信息；同时采集调查对象的静脉血以检测血尿酸等水平，采用基于教育程度的认知受损评价标准评定研究对象的认知功能受损情况，并采用二分类广义估计方程（GEE）分析血尿酸水平与认知功能受损的关联，并进一步分析不同年龄、体重指数（BMI）对象血尿酸水平与认知功能受损的关联。 结果： 1 622名研究对象年龄为（92.2±8.1）岁，其中男性656名（40.4%）；血尿酸为（343.3±86.2）μmol/L；482名（29.7%）认知功能受损。二分类GEE模型分析结果显示，调整相关混杂因素后，与Q1组相比，Q2、Q3、Q4组的认知受损风险逐渐降低，OR（95%CI）值分别为0.99（0.71~1.33）、0.87（0.68~0.94）及0.69（0.48~0.85），且具有线性趋势（P<0.001）；80~89岁年龄组、BMI<24 kg/m2组血尿酸水平与认知功能受损的关联更为显著（P交互值<0.05）。 结论： 在中国长寿地区高龄老年人中高血尿酸水平与认知功能受损患病风险呈负向关联。.
Keywords: Aged, 80 and over; Cognitive impairment; Cross-sectional studies; Longevity; Uric acid.