Utility of standing office blood pressure in detecting hypertension in healthy adults.

Current guidelines recommend office blood pressures (BP) be taken in a seated position when screening for hypertension (HTN). Seated BP is known to have limited accuracy in detecting high BP, while the utility of standing BP in diagnosing HTN is unknown. We conducted a cross-sectional study to determine the incremental value of standing BP in diagnosing HTN. Seated, standing, and 24-h ambulatory BPs (ABPM) were obtained in adults without known cardiovascular disease, HTN, or BP medication use. Presence of HTN was defined by the 2017 ACC/AHA and the 2023 ESH HTN guidelines based on ABPM. Area under the receiver-operating-characteristic curve (AUROC) was used to evaluate the diagnostic accuracy of seated and standing BP. Sensitivity and specificity of standing BP was determined using cut-offs derived from Youden's Index, while sensitivity and specificity of seated BP was determined using the cut-off of 130/80 mmHg and by 140/90 mmHg. Among 125 participants (mean age 49 ± 17 years; 62% female; 24% Black), 33.6% of them had HTN. Sensitivity and specificity of seated systolic BP (SBP) was 43% and 92%, respectively. Cut-offs selected by Youden's index for standing SBP/diastolic BP (DBP) were 124/81 mmHg according to the 2017 ACC/AHA HTN guidelines, and 123.5/83.5 mmHg according to the 2023 ESH HTN guidelines. Sensitivity and specificity of standing SBP was 71% and 67%, respectively. The AUROC of standing SBP (0.81 [0.71-0.92]) was significantly higher than seated SBP (0.70 [0.49-0.91]), when HTN was defined as average 24-h SBP ≥ 125 mmHg. Moreover, the addition of standing to seated SBP (0.80 [0.68-0.92]) improved HTN detection when compared to seated SBP. These patterns were consistent for both the 2017 ACC/AHA and the 2023 ESH definitions for HTN. In summary, standing BP, alone or in combination with seated BP, outperformed seated BP alone in diagnosing HTN in adults.

Exaggerated renal sympathetic nerve and pressor responses during spontaneously occurring motor activity in hypertensive rats.

Stimulation of the mesencephalic locomotor region elicits exaggerated sympathetic nerve and pressor responses in spontaneously hypertensive rats (SHR) as compared with normotensive Wistar-Kyoto rats (WKY). This suggests that central command or its influence on vasomotor centers is augmented in hypertension. The decerebrate animal model possesses an ability to evoke intermittent bouts of spontaneously occurring motor activity (SpMA) and generates cardiovascular responses associated with the SpMA. It remains unknown whether the changes in sympathetic nerve activity and hemodynamics during SpMA are altered by hypertension. To test the hypothesis that the responses in renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) during SpMA are exaggerated with hypertension, this study aimed to compare the responses in decerebrate, paralyzed SHR, WKY, and normotensive Sprague-Dawley (SD) rats. In all strains, an abrupt increase in RSNA occurred in synchronization with tibial motor discharge (an index of motor activity) and was followed by rises in MAP and heart rate. The centrally evoked increase in RSNA and MAP during SpMA was much greater (306 ± 110%) in SHR than WKY (187 ± 146%) and SD (165 ± 44%). Although resting baroreflex-mediated changes in RSNA were not different across strains, mechanically or pharmacologically induced elevations in MAP attenuated or abolished the RSNA increase during SpMA in WKY and SD but had no effect in SHR. It is likely that the exaggerated sympathetic nerve and pressor responses during SpMA in SHR are induced along a central command pathway independent of the arterial baroreflex and/or result from central command-induced inhibition of the baroreflex.

Autonomic dysfunction in muscular dystrophy: a theoretical framework for muscle reflex involvement.

Muscular dystrophies are a heterogeneous group of genetically inherited disorders whose most prominent clinical feature is progressive degeneration of skeletal muscle. In several forms of the disease, the function of cardiac muscle is likewise affected. The primary defect in this group of diseases is caused by mutations in myocyte proteins important to cellular structure and/or performance. That being stated, a growing body of evidence suggests that the development of autonomic dysfunction may secondarily contribute to the generation of skeletal and cardio-myopathy in muscular dystrophy. Indeed, abnormalities in the regulation of both sympathetic and parasympathetic nerve activity have been reported in a number of muscular dystrophy variants. However, the mechanisms mediating this autonomic dysfunction remain relatively unknown. An autonomic reflex originating in skeletal muscle, the exercise pressor reflex, is known to contribute significantly to the control of sympathetic and parasympathetic activity when stimulated. Given the skeletal myopathy that develops with muscular dystrophy, it is logical to suggest that the function of this reflex might also be abnormal with the pathogenesis of disease. As such, it may contribute to or exacerbate the autonomic dysfunction that manifests. This possibility along with a basic description of exercise pressor reflex function in health and disease are reviewed. A better understanding of the mechanisms that possibly underlie autonomic dysfunction in muscular dystrophy may not only facilitate further research but could also lead to the identification of new therapeutic targets for the treatment of muscular dystrophy.

Pre-admission factors and utilization of tutoring services in health professions educational programs.

Pre-admission factors tend to serve as indicators of student success in health professions educational programs, but less is known about the effects that academic assistance programs have on student success. This study sought to determine whether specific pre-admission factors could help to identify students who may require academic support during their health professions education. This retrospective analysis aimed to identify differences in pre-admission variables between those students requiring tutoring and a matched sample of students who did not require tutoring. One-way ANOVA was used to assess differences for dependent variables-age, cumulative GPA (cGPA), science GPA (sGPA), verbal graduate record examination (GRE) score, quantitative GRE score, analytical GRE score and combined GRE score, community college hours, average credit hours per semester, and highest semester credit hour load-across three groups of students who received no tutoring (NT 0 hrs), some tutoring (ST <8 hrs), and more tutoring (MT >8 hrs). Total GRE and average semester hours differentiated NT from ST from MT (p<0.05). A linear regression model with these pre-admission factors found only four of the independent variables to be significant (r2=0.41; p<0.05) in predicting hours of tutoring: quantitative GRE, sGPA, cGPA and average semester hours taken. The combination of lower GRE scores and lighter average semester course load were most predictive of the need for academic assistance as defined by hours of tutoring. While the value of the GRE in admissions processes is generally accepted, the average semester hour load in college can also provide important information regarding academic preparation and the need for tutoring services.

Development, implementation, and short-term effectiveness of an interprofessional education course in a school of health professions.

It is accepted that interprofessional education (IPE) has positive benefits for health profession students, including effective communication, increased teamwork skills, and better appreciation for the roles of other health professions. However, the question remains of how to effectively deliver IPE for health professions students in an educational environment. To address this problem, the University of Texas Southwestern School of Health Professions developed an IPE course, Interdisciplinary Development, Education, and Active Learning (IDEAL), incorporating seven disciplines represented within the school. The hypothesis was that a two-semester exposure to the new curriculum and related activities would have a significant positive influence on students' understanding of the elements required for effective communication (e.g., listening and interpersonal skills), teamwork skills, and understanding the roles of other health professions. An assessment of a student's understanding of communication and teamwork skills was administered on the first and last day of the IDEAL course to test the hypothesis and determine if course objectives of improving student's communication and teamwork skills were met. Questions were divided into three focus areas of teamwork, listening, and interpersonal communication. Findings showed a significant (p < 0.016) increase in scores for all three areas, the largest being in teamwork. Also, results from an anonymous, open-ended survey of the overall IDEAL course at the end of the course showed overwhelming consensus regarding the success and effectiveness of the healthcare team grand rounds presentations from which the students learned about other professions and their roles on the healthcare team in a case-based format.

Are decreases in insular regional cerebral blood flow sustained during postexercise hypotension?

UNLABELLED: Regional cerebral blood flow (rCBF) in the insular cortex (IC), a well-recognized site for central blood pressure (BP) modulation, is decreased at minute 10 during postexercise hypotension (PEH). PURPOSE: To determine whether exercise-induced decreases in IC rCBF are associated with BP changes throughout PEH. METHODS: Ten subjects were studied on three different days using a counterbalanced design with a randomized order for conditions; all were tested during a resting baseline and then at two of three time points postexercise: 10, 30, and 60 min. Data were collected for HR, mean BP, and rCBF using single-photon emission computed tomography as an index of brain activation. RESULTS: Using ANOVA across conditions, there were differences (P < 0.05; mean +/- SD) for HR from baseline at minute 10 (+15 +/- 4 bpm) and minute 30 (+6 +/- 3 bpm) and for mean BP at minute 10 (-11 +/- 4 mm Hg) and minute 30 (-5 +/- 3 mm Hg). There were significant decreases (P < 0.05) in rCBF at both minutes 10 and 30 after exercise in the inferior thalamus and the right inferior IC regions. Although there were no decreases in BP or IC activity at minute 60, changes in right inferior posterior IC activity and BP were strongly correlated (r2 = 0.74; P < 0.05) postexercise. CONCLUSIONS: Findings show that exercise-induced decreases in IC and thalamic activity may be a significant neural factor contributing to at least the first 30 min of PEH.

Exercise-induced decrease in insular cortex rCBF during postexercise hypotension.

UNLABELLED: The insular cortex (IC), a region of the brain involved in blood pressure (BP) modulation, shows decreases in regional cerebral blood flow (rCBF) during postexercise hypotension (PEH). PURPOSE: To determine whether changes in IC neural activity were caused by prior exercise or by changes in BP, this investigation compared patterns of rCBF during periods of hypotension, which was induced by prior exercise (i.e., PEH) and sodium nitroprusside (SNP) infusion and a cold pressor (CP), to restore BP. METHODS: Ten subjects were studied on three different days with randomly assigned conditions: i) resting baseline; ii) PEH; and iii) SNP-induced hypotension (matched to the PEH BP decrease). Data were collected for heart rate (HR) and mean BP, and rCBF was assessed using single-photon emission computed tomography (SPECT) as an index of brain activation. RESULTS: Using ANOVA across conditions, there were differences (P<0.05; mean +/- SD) from baseline during PEH for HR (+12 +/- 3 bpm) and mean BP (-8 +/- 2 mm Hg) and during SNP-induced hypotension (HR = +15 +/- 4 bpm; MBP = -9 +/- 2 mm Hg), with no differences between PEH and SNP. After exercise, there were decreases (P<0.05) in the leg sensorimotor area, anterior cingulate, and the right and left inferior thalamus, right inferior insula, and left anterior insular regions. During SNP-induced hypotension, there were significant increases in the right and left inferior thalamus and the right and left inferior anterior IC. CP during PEH increased BP and IC activity. CONCLUSIONS: Data show that reductions in IC neural activity are not caused by acute BP decreases. Findings suggest that exercise can lead to a temporary decrease in IC neural activity, which may be a significant neural factor contributing to PEH.

Academic incentives for students can increase participation in and effectiveness of a physical activity program.

The authors sought to determine whether a greater academic incentive would improve the effectiveness and student adherence to a 12-week voluntary exercise program designed to decrease students' percentage of body fat. They randomly assigned 210 students to 1 of 2 groups with different academic reward structures. The group with the greater reward structure showed better exercise adherence and lost more body fat than those without the additional incentive. These findings suggest that an academic incentive can increase overall student adherence to a voluntary exercise program and can boost the effectiveness of the program in a university environment. The findings also have potential implications for on-campus promotion of physical activity.

Can relaxation lower metaboreflex-mediated blood pressure elevations?

PURPOSE: Relaxation can lower resting blood pressure, and this investigation sought to determine whether relaxation could reduce mean blood pressure (MBP) elevations produced by postexercise circulatory occlusion (PECO). METHODS: Sixteen volunteers trained with relaxation and were able to decrease MBP at rest by at least 5 mm Hg within 2 min. Subjects performed four tests assigned randomly: i). rest with cuff occlusion, ii). rest and cuff occlusion with relaxation, iii). hand-grip exercise followed by PECO rest with cuff occlusion, and iv) hand-grip exercise followed by PECO with relaxation. Data for HR and MBP were collected using a Finapres; ratings of relaxation and discomfort from cuff occlusion were obtained using a 1- to 10-unit scale. Stroke volume (SV) and HR were collected from six subjects to calculate cardiac output and total peripheral conductance (TPC). Dependent variables were compared using an ANOVA. RESULTS: HR (mean +/-SD) was lower during both relaxation conditions as compared with control (-7 +/- 4 bpm vs -2 +/- 3 bpm; P< 0.05). The MBP was reduced during relaxation alone (-6 +/- 3.7 mm Hg; < 0.05) but not during PECO with relaxation. The rating of relaxation was higher during relaxation (6.8 +/- 1.3 units) versus control (3.5 +/- 1.2 units), but ratings were not different between relaxation conditions. Ratings of discomfort were higher during PECO ( P< 0.05). Relaxation did not significantly alter CO or SV (N= 6). During relaxation alone, TPC was increased (0.046 +/- 0.001 vs 0.049 +/- 0.002 L.min.mm Hg; P< 0.05). However, TPC was significantly increased during PECO with relaxation. CONCLUSIONS: These findings suggest that although relaxation can affect cardiovascular regulation and lower HR and MBP at rest, this central signal cannot lower reflex increases in blood pressure originating from a peripheral metabolic stimulus.