70岁及以上人群收缩压与认知障碍的相关关系:一项以西安市鄠邑区农村人群为基础的横断面调查

Correlation between systolic blood pressure and cognitive impairment in people aged 70 years and above:A cross-sectional survey based in a rural area of Xi'an,China

目的分析70岁及以上人群血压与认知障碍的相关关系。方法选取2014年10月—2015年3月西安市鄠邑区某村≥70岁全部常住村民作为研究对象,测定坐位血压。应用简易精神状态量表(MMSE)评估认知功能,以MMSE评分低于分界值作为认知障碍的判断标准,即文盲≤17分,小学文化程度≤20分,中学及以上文化程度≤24分。采用多因素Logistics回归校正混杂因素。结果全村共有≥70岁常住村民236人,实际完成血压测量及MMSE测查者217人(占92.0%),排除既往卒中患者后纳入186人,其中男性87人(46.8%),年龄70~85岁,平均(74.17±3.97)岁,符合认知障碍者64人(34.4%)。收缩压(SBP)为(143.45±20.25)mmHg(1 mmHg=0.133 kPa),≤139 mmHg者(较低SBP组)69人,140~159 mmHg者(参照组)66人,≥160 mmHg者(较高SBP组)51人。单因素分析显示,较低SBP组(40.6%)、较高SBP组(37.3%)认知障碍患病率均高于参照组(25.8%,P=0.171);多因素Logistics回归分析显示,与参照组相比,较低SBP组(OR=2.99,95%CI 1.19~7.53,P=0.020)或较高SBP组(OR=2.66,95%CI 0.97~7.28,P=0.057)认知障碍患病风险升高。舒张压(DBP)为(82.48±10.34)mmHg,≤89 mmHg者136人(73.1%),90~99 mmHg者29人(15.6%),≥100 mmHg者21人(11.3%),3组间认知障碍患病率无显著差异(35.3%vs.34.5%vs.28.6%,P=0.833)。多因素Logistics回归分析显示,3个DBP组间认知障碍患病风险无显著差异(P=0.714)。结论在≥70岁人群横断面调查中,SBP低于140 mmHg或者高于160 mmHg均与基于MMSE判定的认知障碍患病风险升高相关。DBP与认知障碍之间未发现显著相关性。

Objective To study the relationship between blood pressure and cognitive impairment in people aged≥70 years.Methods From October 2014 to March 2015,blood pressure and global cognitive function information were collected from the participants aged≥70 years who lived in a village in the suburbs of Xi'an,China,during in-person interviews.Mini-mental State Examination(MMSE)was used to evaluate global cognitive function.Cognitive impairment was defined as the MMSE score lower than the cutoff value.Specifically,the cutoff value was≤17 for the illiterate,≤20 for the primary school educated,and≤24 for those educated at the junior high school level and above.Multivariate Logistic regression was performed to correct confounding factors.Results A total of 236 permanent residents aged≥70 lived in the village.Of them 217 subjects(92.0%)completed blood pressure measurement and MMSE examination and 31 subjects were excluded because of previous stroke.A total 186 subjects were enrolled in the analysis,including 87 males(46.8%).The age ranged from 70 to 85 years(mean 74.17±3.97 years),and 64 people(34.4%)were diagnosed with cognitive impairment.The mean systolic blood pressure(SBP)was(143.45±20.25)mmHg.Totally 69 subjects had SBP of≤139 mmHg,66 subjects had SBP of 140-159 mmHg,and 51 subjects had SBP of≥160 mmHg.Univariate analysis showed that both subjects with SBP≤139 mmHg and those with SBP≥160 mmHg had a higher prevalence of cognitive impairment compared with the subjects with SBP of 140-159 mmHg(≤139 mmHg vs.140-159 mmHg vs.≥160 mmHg,40.6%vs.25.8%vs.37.3%,P=0.171).Multivariate Logistic regression analysis showed that compared with the reference group(140-159 mmHg),both subjects with a lower SBP(OR=2.99,95%CI 1.19-7.53,P=0.020)and those with a higher SBP(OR=2.66,95%CI 0.97-7.28,P=0.057)had a higher risk of cognitive impairment.The mean diastolic blood pressure(DBP)was(82.48±10.34)mmHg.136(73.1%)subjects had DBP of≤89 mmHg,29(15.6%)subjects had DBP of 90-99 mmHg,and 21(11.3%)ones had DBP of≥100 mmHg.There was no significant difference in the prevalence of cognitive impairment among the three groups(≤89 mmHg vs.90-99 mmHg vs.≥100 mmHg,35.3%vs.34.5%vs.28.6%,P=0.833).Multivariate Logistic regression analysis showed no significant correlation between cognitive impairment and DBP(P=0.714).Conclusion In this cross-sectional survey,SBP below 140 mmHg or above 160 mmHg is associated with an increased risk of cognitive impairment in people aged 70 years or above.However,no significant correlation was found between DBP and cognitive impairment.