Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands Department of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, The Netherlands.
Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands.
J Neurol Neurosurg Psychiatry. 2016 Feb;87(2):144-8. doi: 10.1136/jnnp-2014-309824. Epub 2015 Mar 6.
Orthostatic hypotension has been associated with impaired cognitive function, but cognitive function during orthostatic hypotension has hardly been studied. We studied the effect of orthostatic hypotension, induced by head-up tilt (HUT), on sustained attention in patients with autonomic failure.
We studied the sustained attention to response task (SART) in the supine position and during HUT in 10 patients with autonomic failure and 10 age-matched and sex-matched controls. To avoid syncope, the tilting angle was tailored to patients to reach a stable systolic blood pressure below 100 mm Hg. Controls were all tilted at an angle of 60°. Cerebral blood flow velocity, blood pressure and heart rate were measured continuously.
In patients, systolic blood pressure was 61.4 mm Hg lower during HUT than in the supine position (p<0.001). Patients did not make more SART errors during HUT than in the supine position (-1.3 errors, p=0.3). Controls made 2.3 fewer errors during SART in the HUT position compared to the supine position (p=0.020). SART performance led to an increase in systolic blood pressure (+11.8 mm Hg, p=0.018) and diastolic blood pressure (+5.8 mm Hg, p=0.017) during SART in the HUT position, as well as to a trend towards increased cerebral blood flow velocity (+3.8 m/s, p=0.101).
Orthostatic hypotension in patients with autonomic failure was not associated with impaired sustained attention. This might partly be explained by the observation that SART performance led to a blood pressure increase. Moreover, the upright position was associated with better performance in controls and, to a lesser extent, also in patients.
直立性低血压与认知功能障碍有关，但直立性低血压期间的认知功能几乎没有研究过。我们研究了自主衰竭患者中由头高位倾斜（HUT）引起的直立性低血压对持续性注意力的影响。
我们在 10 名自主衰竭患者和 10 名年龄和性别匹配的对照组中，在仰卧位和 HUT 期间研究了持续性注意力任务（SART）。为了避免晕厥，倾斜角度根据患者量身定制，以达到稳定的收缩压低于 100mmHg。对照组均倾斜 60°。连续测量脑血流速度、血压和心率。
与仰卧位相比，患者 HUT 时的收缩压低 61.4mmHg（p<0.001）。与仰卧位相比，患者在 HUT 期间并没有在 SART 中犯更多的错误（少 1.3 个错误，p=0.3）。与仰卧位相比，对照组在 HUT 位置进行 SART 时的错误少 2.3 个（p=0.020）。在 HUT 位置进行 SART 时，SART 表现会导致收缩压升高（+11.8mmHg，p=0.018）和舒张压升高（+5.8mmHg，p=0.017），并且脑血流速度有升高的趋势（+3.8m/s，p=0.101）。
自主衰竭患者的直立性低血压与注意力持续性障碍无关。这可能部分解释了 SART 表现导致血压升高的观察结果。此外，直立位在对照组中表现更好，在患者中表现稍差。
