Does the average daily blood pressure correlate with hypertensive cerebrovascular disease better than the casual pressure, as has been reported in other target organ involvement? We investigated the associations of two abnormal findings on brain magnetic resonance imaging suggestive of a vascular etiology, low intense foci (lacunae), and periventricular hyperintense lesions on T,-and Tj-weighted images, with both office and average daily blood pressure values in a population of 73 healthy normotensive and hypertensive elderly individuals (70 ± 6 years old). Lacunae were detected in 34 subjects (47%); the number per subject ranged from 0 to 19 and was significantly correlated with advancing age. Furthermore, these changes were supposedly related to the average of noninvasive ambulatory (24-hour and during awake and asleep periods) pressure recordings but not to office pressures. The grade of periventricular hyperintensity was also significantly associated with advancing age and the average of ambulatory systolic pressure recordings, particularly during sleep, but not with office blood pressure. In comparisons of normotensive, "office hypertensive," and hypertensive subgroups, abnormalities on magnetic resonance imaging were appropriate to the level of the 24-hour blood pressure measurements but not to that of clinic pressure. In hypertensive patients, the presence of electrocardiographic evidence of left ventricular hypertrophy was also associated with greater abnormalities on magnetic resonance imaging. We conclude that ambulatory blood pressure monitoring is superior to casual pressure measurements in predicting latent cerebrovascular disease, which is unexpectedly common in apparently healthy elderly subjects. {Hypertension 1990;16:692-699) I t is well known that pressures measured in the office or clinic may not be representative of the patient's blood pressure throughout the day. 1The correlations between target organ damage and different measures of blood pressure have been compared in several studies. 2^ In the heart, ambulatory blood pressure measurements have given better correlations than clinic readings with left ventricular hypertrophy as evaluated by electrocardiogram, chest x-ray, and echocardiography.4 -7 Hypertensive retinopathy 48 was also found to correlate more closely with ambulatory pressures than with casual pressures. These results suggest that the adverse effects of blood pressure on the heart and peripheral vessels (including the optic fundi) depend on the average level of pressure over time. To date, however, there

Serotonin enhancement during developmental stages restores autism symptoms in a mouse model of human 15q11-13 duplication.

A validation study of the continuous noninvasive tonometric blood pressure monitor called JENTOW was performed in 20 normotensive subjects and 10 hypertensive patients. Tonometric and intra-arterial blood pressures were simultaneously recorded at supine rest and during a Valsalva maneuver and tilting test The results of the strict evaluation of the instrument's capacity for reproducing intra-arterial blood pressure were as follows: 1) The overall frequency response of the transcutaneous blood pressuremonitoring system based on arterial tonometry was flat, with negligible delay to intra-arterial blood pressure in the range of 0-5 Hz.2) The largest discrepancy between intra-arterial and tonometric pressure waveforms was found at the early systolic phase; except for this phase, the tonometric waveform was almost equal to the intra-arterial waveform.3) The beat-to-beat variability of tonometric pressure corresponded to that of intra-arterial pressure almost perfectly in the physiologically significant frequency range of 0-0.5 Hz. 4) During resting conditions, the averages of the systolic and diastolic values measured tonometrically corresponded well to those measured intra-arterially. 5) The changes in the betweenmethod discrepancy of blood pressure values during the Valsalva maneuver were statistically significant but small (<5 mm Hg). 6) No significant effect of postural tilting was found on the between-method discrepancy. We conclude that this method is clinically acceptable and reliable except for its limited capacity for recording the higher frequency intra-arterial waveform and for responding to the relatively rapid and large transient changes in blood pressure. invasive methods for continuously monitoring arterial blood pressure has been expected for many years. A noninvasive technique, arterial tonometry, was invented in 1963. ^ A tonometric device has been recently improved and has resulted in an instrument called JENTOW. The objective of this study was to evaluate the accuracy of the tonometer JENTOW in reproducing intra-arterial blood pressure. Our interests in the comparison of the blood pressures measured by the two methods were focused on the following points: 1) the correspondence of the waveforms of blood pressure, 2) the correlation of beat-to-beat variabilities, and 3) the agreement of blood pressure values during resting conditions and during laboratory maneuvers that induced rapid and large transient changes in blood pressure. This study demonstrated the reliability and limitations of this noninvasive method for reproducing intra-arterial blood pressure. Methods SubjectsTwenty normotensive volunteers and 10 patients with uncomplicated essential hypertension (26 men, four women; mean age, 42.3 years; range, 20-74 years) were

Background and Purpose: Controversies exist whether incidental neuroradiological brain lesions in the elderly are associated with depressed neuropsychological function. To address this important issue in a cross-sectional study, we related brain lesions on magnetic resonance imaging to a variety of cognitive and neurobehavioral function tests in an independent, normal elderly population.Methods: We studied 73 independent asymptomatic elderly individuals (mean±SD age 70 ±6 years) to determine the relations between degree of brain atrophy, location and number of "lacunes," and grade of periventricular hyperintense lesions with a variety of cognitive and neurobehavioral function scores.Results: We found that severity of neuroradiological changes increased while neuropsychological function scores declined with age. After adjustment for the effect of age, advanced periventricular hyperintensities, but not brain atrophy or patchy "lacunar" lesions, were associated with declines in all neuropsychological functions tested.Conclusion: We conclude that incidental advanced periventricular diffuse or patchy white matter changes may play a role in the development of cognitive and neurobehavioral impairments in apparently normal elderly persons. (Stroke 1992;23:175-180)

To examine the influence of hypertension on cardiovascular variability in elderly subjects, we measured spontaneous beat-to-beat blood pressure (BPV) and heart rate variability (HRV) in elderly subjects with or without hypertension at rest and during tilting. The study group consisted of 23 community-dwelling, male elderly subjects (aged 62-75 years) and was divided into two groups, i.e., a hypertensive group (HT group; n=11) and normotensive group (NT group; n=12). According to the modeling and decomposing algorithm of an autoregressive process, we estimated the component power of low-frequency (LF; 0.03-0.15 Hz) and high-frequency components (HF; respiratory frequency) of BPV and HRV by power spectral analysis. We also measured plasma norepinephrine (PNE) levels in the two groups at rest and during tilting. In the HT group, we found that the amplitude of LF-BPV was greater (p < 0.05) and its relative change by postural tilting was smaller (p< 0.05) than those in the NT group. We found no significant difference in the amplitude of LF-HRV and HF-HRV between the two groups, and found no significant response of the amplitude of LF-HRV and HF-HRV to postural tilting. We also found no differ ence in PNE level between the two groups at rest or during tilting. These results suggest that the regulatory function of sympathetic vasomotor activity assessed by power spectral analysis of BPV is altered in hypertensive elderly subjects, although the influence of hypertension on the autonomic control of the heart is less dominant in the elderly. (Hypertens Res 1996; 19: 9-16) Key Words: spectral analysis, hypertension, elderly, sympathetic activity, orthostatic stress Power spectral analysis of heart rate and blood pressure variability has been used to assess the autonomic control of the cardiovascular system (1-5). In healthy humans, power spectral analysis of spontaneous beat-to-beat blood pressure variability (BPV) and heart rate variability (HRV) has demonstrated two major spectral components, i.e., a lowfrequency (LF) component at 0.03-0.15 Hz and a high-frequency (HF) component at respiratory frequency (1-5). Earlier studies (1, 3, 4, 6) suggest that 1) the LF component of BPV corresponds to Mayer waves in humans; 2) the HF component of BPV (Traube-Hering waves) depends mostly on the mechanical effects of respiration; 3) the LF component of HRV reflects Mayer waves through the baroreceptor reflex; and that 4) the HF component of HRV corresponds to the respiratory sinus arrhythmia and reflects parasympathetic activity. Recent human studies by power spectral analysis (1, 7) and early experimental studies (8-10) suggest that the Mayer waves reflect vasomotor tone mediated by sympathetic nervous activity.Increased sympathetic nervous activity plays an important role in the pathogenesis of essential hypertension.Increased plasma norepinephrine (PNE) levels (11, 12) and peroneal nerve activity (13) have been reported in hypertensive subjects. In power spectral analysis of HRV, sympathetic predominance was shown in hyperten...