Cognitive performance and cerebral blood flow in essential hypotension

Abstract

In the present study cerebral blood flow was assessed in 40 subjects with chronically low blood pressure and 40 normotensive controls at resting conditions and during the execution of a cued reaction time task. Blood flow velocities were recorded by means of transcranial Doppler sonography in both middle cerebral arteries. In hypotensives flow velocity at rest was reduced bilaterally. During the anticipation of the stimuli, which the subjects had to respond to, a predominantly right hemispheric increase of flow velocity was observed in both groups. This increase was significantly less pronounced in the hypotensive group. Hypotensives showed longer reaction times, and there was a negative correlation between the extent of the flow velocity increase and the reaction times. This study is the first to demonstrate a reduced cerebral perfusion and maladaption of blood flow to cognitive demands due to essential hypotension.

Transcranial Doppler Sonography in Studies of Mental Effort

“…Another pattern of results is apparent in several studies, where CBFv is comparable between the comparison groups, but the clinical population shows less modulation or lateralization of blood flow, compared to healthy controls. This result was reported for individuals with schizophrenia (Schuepback et al, 2007) and for hypotensive compared to normotensive patients (Duschek & Schandry, 2004).…”

“…Cognitive testing has been complemented with TCD measures of CBFv to study the executive-function skills (Kral & Brown, 2004;Kral et al, 2003) and language functioning (Sanchez, Schatz, & Roberts, 2010) of children with sickle cell disease; to examine the executive-function deficits, particularly those involved in planning, associated with schizophrenia (Feldmann et al, 2006;Schuepback, Weber, Kawohl, & Hell, 2007); in the attention skills of participants with and without hypotension (Duschek & Schandry, 2004); in elderly adults with versus without depression (Tiemeier et al, 2002); to examine executive functioning in patients with Huntington's disease versus healthy controls (Deckel, Cohen, & Duckrow, 1998); and in the mental activity patterns of healthy individuals versus individuals recovering from stroke versus individuals who have shown no recovery from stroke (Bragoni et al, 2000). The results of these patterns are not as simple as "clinical conditions are associated with slower CBFv"-although that is what one sees for planning by individuals with schizophrenia compared to healthy controls (Feldmann et al, 2006), for depressed individuals compared to their nondepressed cohort (Tiemeier et al, 2002), and for individuals with Huntington's disease compared to healthy individuals (Deckel et al, 1998).…”

Inter-day reliability of blood pressure and cerebral blood flow velocities in persons with spinal cord injury and intact controls

“…However, increases in BP that are associated with AD can cause severe headaches and dizziness episodes which adversely impact daily activities 10 and in extreme cases can result in cerebral hemorrhage and death. [11][12][13][14] In the general population persistent hypotension may result in cerebral hypoperfusion, 15,16 and it was recently reported that chronic cerebral hypoperfusion, secondary to diabetes, contributed to accelerated cognitive decline and neuronal cell death. 17 Further, an increased incidence of hemorrhagic and ischemic stroke was noted in the Taiwanese SCI population (n=2806) compared to propensity-score matched controls (n = 28,060), which the authors speculate may relate to fluctuations in BP.…”

Modulations of autonomic cardiovascular control following acute alpha-adrenergic treatment in chronic hypotension

“…1,2 Reduced cognitive performance, as well as diminished cerebral blood flow and cortical activation have been documented in this condition. [3][4][5] According to the World Health Organization (WHO), 6 hypotension is to be diagnosed when systolic blood pressure falls below 100 mm Hg in women and 110 mm Hg in men. The condition of chronic ('essential') hypotension must be distinguished from secondary hypotension, caused, for example, by blood loss or medication, as well as from the orthostatic form, that is, circulatory problems when assuming an upright position.…”