意大利学者研究发现，在接受抗高血压药物治疗的痴呆和轻度认知障碍(MCI)的老年患者中，低的日间收缩压与较大程度的认知功能下降独立相关。论文3月2日在线发表于《美国医学会杂志•内科学》(JAMA Intern Med)。

        该队列研究共分析了172例痴呆和MCI患者，平均年龄为79[标准差(SD)=5]岁，平均简易智能精神状态检查量表(MMSE)得分为22.1(SD=4.4)，对这些患者进行中位时间为9个月的随访，以评估诊室血压、动态血压监测或使用抗高血压药物是否可预测具有明显痴呆和MCI患者的认知功能下降的进展情况。

        结果为，这些患者中，68.0%有痴呆，32.0%存在MCI，69.8%正在接受抗高血压药物治疗。与日间收缩压处于中间1/3区间(129～144mmHg)和最高1/3区间(≥145mmHg)的患者相比，日间收缩压处于最低1/3区间(收缩压≤128mmHg)患者的认知功能下降程度更大(P=0.002，P=0.003)。

        根据是否接受抗高血压药物治疗对患者进行分层，则低的日间收缩压与较大程度的认知功能下降间的相关性仅存在于接受抗高血压药物治疗的患者中。

        在纳入了年龄、基础MMSE评分和血管合并症评分的多变量模型中，对于痴呆和MCI两个亚组的患者，较大程度的认知功能下降与低的日间收缩压及抗高血压药物治疗二者的交互作用项之间存在独立相关性。

        诊室收缩压与MMSE评分改变间的相关性较弱，其他动态血压监测变量与MMSE评分改变无相关性。

        参考文献：Enrico Mossello, MD, PhD, et al. JAMA Intern Med. Published online March 02, 2015. doi:10.1001/jamainternmed.2014.8164

 March 02, 2015
Effects of Low Blood Pressure in Cognitively Impaired Elderly Patients Treated With Antihypertensive Drugs ONLINE FIRST
Enrico Mossello, MD, PhD1; Mariachiara Pieraccioli, MD1; Nicola Nesti, MD1; Matteo Bulgaresi, MD1; Chiara Lorenzi, MD1; Veronica Caleri, MD, PhD2; Elisabetta Tonon, MD, PhD2; M. Chiara Cavallini, MD, PhD1; Caterina Baroncini, MD1; Mauro Di Bari, MD, PhD1; Samuele Baldasseroni, MD, PhD1; Claudia Cantini, MD, PhD2; Carlo A. Biagini, MD2; Niccolò Marchionni, MD1; Andrea Ungar, MD, PhD1
JAMA Intern Med. Published online March 02, 2015. doi:10.1001/jamainternmed.2014.8164

ABSTRACT
Importance  The prognostic role of high blood pressure and the aggressiveness of blood pressure lowering in dementia are not well characterized.
Objective  To assess whether office blood pressure, ambulatory blood pressure monitoring, or the use of antihypertensive drugs (AHDs) predict the progression of cognitive decline in patients with overt dementia and mild cognitive impairment (MCI).
Design, Setting, and Participants  Cohort study between June 1, 2009, and December 31, 2012, with a median 9-month follow-up of patients with dementia and MCI in 2 outpatient memory clinics.
Main Outcomes and Measures  Cognitive decline, defined as a Mini-Mental State Examination (MMSE) score change between baseline and follow-up.
Results  We analyzed 172 patients, with a mean (SD) age of 79 (5) years and a mean (SD) MMSE score of 22.1 (4.4). Among them, 68.0% had dementia, 32.0% had MCI, and 69.8% were being treated with AHDs. Patients in the lowest tertile of daytime systolic blood pressure (SBP) (≤128 mm Hg) showed a greater MMSE score change (mean [SD], −2.8 [3.8]) compared with patients in the intermediate tertile (129-144 mm Hg) (mean [SD], −0.7 [2.5]; P = .002) and patients in the highest tertile (≥145 mm Hg) (mean [SD], −0.7 [3.7]; P = .003). The association was significant in the dementia and MCI subgroups only among patients treated with AHDs. In a multivariable model that included age, baseline MMSE score, and vascular comorbidity score, the interaction term between low daytime SBP tertile and AHD treatment was independently associated with a greater cognitive decline in both subgroups. The association between office SBP and MMSE score change was weaker. Other ambulatory blood pressure monitoring variables were not associated with MMSE score change.
Conclusions and Relevance  Low daytime SBP was independently associated with a greater progression of cognitive decline in older patients with dementia and MCI among those treated with AHDs. Excessive SBP lowering may be harmful for older patients with cognitive impairment. Ambulatory blood pressure monitoring can be useful to help avoid high blood pressure overtreatment in this population.