Seul-Ki Jeong, M.D., Hae-Sung Nam, M.D., Min-Ho Shin, M.D., Sun-Seok Kweon, M.D., Myong-Ho Son, M.D., Eui-Ju Son, M.D., Jae-Min Kim, M.D., Ki-Hyun Cho, M.D. Background: It has been reported that the association between blood pressure and cognitive impairment could be modified by factors such as gender, education, and Apo E genotypes. This study was aimed to investigate whether age could also be a modifier of the association. Methods: The study group consisted of 489 participants aged 65 years or over who lived in Namwon, Korea. The presence of hypertension was ascertained by the measurement of their resting blood pressure. A cognitive impairment was considered to be present when a Korean Mini-Mental State Examination score was less than 19 (30 th percentile). Results: A higher systolic blood pressure was significantly associated with cognitive impairment, after an adjustment for age, gender, education, and occupation. However, the significance was lost in subjects aged 71 or over. Conclusions: High systolic blood pressure is a factor strongly associated with cognitive impairment in an aged population. However, in the subjects with far advanced age, the association is not significant. Further studies are required to elucidate whether blood pressure lowering strategies should be differentiated according to age in order to reduce cognitive impairment. J Korean Neurol Assoc 22(1):16 21, 2004 Key Words: Hypertension, Blood pressure, Cognitive impairment, Age 서론 대한신경과학회지 22 권 1 호
대상과방법 22 권 1 호대한신경과학회지
결과 Table 2. Associations between hypertension / blood pressure (BP) and cognitive impairment* OR (95% CI) P Hypertension (reported) 1.51 (0.88-2.58) 0.138 Systolic BP, 10 mmhg increment Diastolic BP, 10 mmhg increment 1.15 (1.04-1.27) 0.005 1.16 (0.97-1.39) 0.095 *Cognitive impairment is defined as a Korean Mini-Mental State Examination score<19 (30th percentile), Hypertension / blood pressure variables are analyzed separately in multiple logistic regression models, adjusted for age, gender, education, and occupation. OR; odds ratio, CI; confidence interval. Table 1. Characteristics of the participants according to cognitive status Total sample (n=489) K-MMSE score 0~18 (n=180) 19~30 (n=309) P* Socio-demographic characteristics Age, mean±sd years Women, % No education, % Manual occupation, % Hypertension / blood pressure (BP) Hypertension (reported), % Use of antihypertensive medication, % Systolic BP, mean±sd mmhg Diastolic BP, mean±sd mmhg 71.9±5.6 63.2 73.4 60.4 22.9 14.6 137.8±23.0 80.3±12.3 74.1±6.1 87.8 96.6 46.3 24.4 16.5 141.2±23.6 81.8±12.3 70.7±4.8 48.9 59.9 68.5 22.0 13.5 135.8±22.5 79.5±12.2 *P value by χ 2 test or Student t-test as appropriate, K-MMSE; Korean Mini-Mental State Examination 0.548 0.371 0.013 0.039 대한신경과학회지 22 권 1 호
Table 3. Associations between hypertension / blood pressure (BP) and cognitive impairment, stratified by different age dichotomy Age, years Hypertension (reported) Systolic BP, 10 mmhg increment Diastolic BP, 10 mmhg increment OR (95% CI) P* OR (95% CI) P* OR (95% CI) P* < 69 (n=163) 69 (n=326) 2.35(0.82-6.75) 1.18(0.61-2.88) 0.179 1.34(1.10-1.61) 1.05(0.93-1.19) 0.014 1.38(0.99-1.92) 1.10(0.87-1.39) 0.189 < 70 (n=194) 70 (n=295) 2.03(0.76-5.43) 1.23(0.62-2.43) 0.326 1.32(1.11-1.58) 1.06(0.93-1.20) 0.032 1.43(1.05-1.95) 1.10(0.86-1.40) 0.169 < 71 (n=228) 71 (n=261) 2.20(0.88-5.54) 1.17(0.57-2.39) 0.225 1.35(1.14-1.61) 1.05(0.92-1.19) 0.024 1.49(1.11-2.00) 1.05(0.82-1.35) 0.095 < 72 (n=263) 72 (n=226) 1.74(0.75-4.02) 1.28(0.60-2.72) 0.498 1.28(1.09-1.50) 1.06(0.93-1.22) 0.071 1.43(1.09-1.89) 1.06(0.82-1.38) 0.103 < 73 (n=297) 73 (n=192) 1.27(0.59-2.72) 0.65(0.71-3.82) 0.888 1.19(1.04-1.37) 1.10(0.94-1.28) 0.358 1.26(0.99-1.62) 1.18(0.88-1.59) *Likelihood ratio test for interaction between age dichotomy and hypertension / blood pressure. Each multiple logistic regression models were adjusted for age, gender, education, and occupation. 0.607 고찰 22 권 1 호대한신경과학회지
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