LBPS 03-11 INFLUENCE OF NIGHT SHIFT ROTATION TOWARDS DIURNAL VARIATION OF BLOOD PRESSURE OF THE CLINICAL CLERKS COMPARED WITH PRECLINICAL STUDENTS

Epidemiological data indicate that the risk of neurally mediated syncope is substantially higher in the morning. Syncope is precipitated by cerebral hypoperfusion, yet no chronobiological experiment has been undertaken to examine whether the major circulatory factors, which influence perfusion, show diurnal variation during a controlled orthostatic challenge. Therefore, we examined the diurnal variation in orthostatic tolerance and circulatory function measured at baseline and at presyncope. In a repeated-measures experiment, conducted at 0600 and 1600, 17 normotensive volunteers, aged 26 ± 4 yr (mean ± SD), rested supine at baseline and then underwent a 60° head-up tilt with 5-min incremental stages of lower body negative pressure until standardized symptoms of presyncope were apparent. Pretest hydration status was similar at both times of day. Continuous beat-to-beat measurements of cerebral blood flow velocity, blood pressure, heart rate, stroke volume, cardiac output, and end-tidal Pco2 were obtained. At baseline, mean cerebral blood flow velocity was 9 ± 2 cm/s (15%) lower in the morning than the afternoon ( P < 0.0001). The mean time to presyncope was shorter in the morning than in the afternoon (27.2 ± 10.5 min vs. 33.1 ± 7.9 min; 95% CI: 0.4 to 11.4 min, P = 0.01). All measurements made at presyncope did not show diurnal variation ( P > 0.05), but the changes over time (from baseline to presyncope time) in arterial blood pressure, estimated peripheral vascular resistance, and α-index baroreflex sensitivity were greater during the morning tests ( P < 0.05). These data indicate that tolerance to an incremental orthostatic challenge is markedly reduced in the morning due to diurnal variations in the time-based decline in blood pressure and the initial cerebral blood flow velocity “reserve” rather than the circulatory status at eventual presyncope. Such information may be used to help identify individuals who are particularly prone to orthostatic intolerance in the morning.

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Light therapy improves diurnal blood pressure control in night shift workers via reduction of catecholamines

Journal of Hypertension ◽

10.1097/hjh.0000000000002848 ◽

2021 ◽

Vol Publish Ahead of Print ◽

Author(s):

Juliane Hannemann ◽

Anika Laing ◽

Benita Middleton ◽

Jonathan Cridland ◽

Bart Staels ◽

...

Keyword(s):

Blood Pressure ◽

Blood Pressure Control ◽

Night Shift ◽

Light Therapy ◽

Pressure Control ◽

Shift Workers

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Diurnal variation of blood pressure; reproducibility and association with left ventricular hypertrophy in hemodialysis patients

Blood Pressure Monitoring ◽

10.1097/00126097-200502000-00006 ◽

2005 ◽

Vol 10 (1) ◽

pp. 25-32 ◽

Cited By ~ 37

Author(s):

Mahboob Rahman ◽

Valerie Griffin ◽

Robert Heyka ◽

Brian Hoit

Keyword(s):

Blood Pressure ◽

Left Ventricular Hypertrophy ◽

Diurnal Variation ◽

Ventricular Hypertrophy ◽

Hemodialysis Patients ◽

Left Ventricular

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Diurnal Corrected QT Interval and QT Dispersion Variation in Non-Alcoholic Cirrhotic Patients and Healthy Control: A Case-Control Study, Iran

Shiraz E-Medical Journal ◽

10.5812/semj.97542 ◽

2020 ◽

Vol In Press (In Press) ◽

Author(s):

Taghi Amiriani ◽

Vahid Khori ◽

Ali Davarian ◽

Niloofar Rajabli ◽

Mahsa Niknam ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Diurnal Variation ◽

Healthy Subjects ◽

Alcoholic Cirrhosis ◽

Qt Dispersion ◽

Qtc Interval ◽

Healthy Controls ◽

Cirrhotic Patients ◽

The Mean

Background: Cirrhosis could lead to a long corrected QT (QTc) interval in a subgroup of patients, but there are spare data on its diurnal variation. Objectives: The present study aimed to determine the diurnal variation of QTc interval and its relationship to heart rate and blood pressure variation during 24-hour Holter-monitoring in non-alcoholic cirrhosis in comparison with the healthy controls. Methods: The study population comprised 15 patients with non-alcoholic cirrhosis and 15 healthy subjects, undergoing 24-hour electrocardiogram (ECG), heart rate, and blood pressure monitoring. The mean QT interval, mean QTc, maximum and minimum QT, QT dispersion (QT disp), heart rate, and mean arterial blood pressure were measured for each person for 24 hours. Liver stiffness measurement (LSM) was performed by FibroScan® 502 machine (EchoSense, Paris, France, 5 MHz). The results were demonstrated as percentages and mean ± SD. P value ≤ 0.05 was considered significant. Results: Mean QTc was significantly higher in cirrhosis (438 ms) than healthy controls (401.7 ms) (P = 0.03). The mean heart rate was significantly different in cirrhotic patients (79.6 ± 2.9/bpm) compared to healthy controls (72.47 ± 2.0/bpm) (P = 0.05). Conclusions: In this study, QTc was prolonged and increased with the severity of cirrhosis, and its diurnal variation in cirrhosis was different from healthy subjects.

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The Relationship between Nutritional Status, Sleep Duration, Stress Level with Blood Pressure of Nurse Night Shift in the Hospital: Cohort Study

International Journal of Human and Health Sciences (IJHHS) ◽

10.31344/ijhhs.v4i1.120 ◽

2019 ◽

Vol 4 (1) ◽

pp. 55

Author(s):

Salmawati Salmawati ◽

Ari Natalia Probandari ◽

Sapja Anantanyu

Keyword(s):

Blood Pressure ◽

At Risk ◽

Nutritional Status ◽

Sleep Duration ◽

Stress Level ◽

Night Shift ◽

Anthropometric Measurement ◽

Short Sleep Duration ◽

Stress Levels ◽

The Relationship

Objective: Hypertension as a cardiovascular disease occurs due to an uncontrolled increase in blood pressure. Night shift nurses with more overweight, short sleep duration, and excessive stress levels are at risk of increase blood pressure. This study aims to analyze how the relationship between obesity, nutritional status, sleep duration and stress level influence the blood pressure of the night shift nurses.Materials and methods: The subjects in this study were night shift nurses in four hospitals. The dependent variable was blood pressure and the independent variables were nutritional status, sleep duration, and stress levels. This study was an observational analysis with a perspective cohort design in which the subjects were 312 night shift nurses. Nutritional status were identified from Body Mass Index (BMI) through anthropometric measurement, sleep duration by looking at average hours of sleep during the night service, stress levels through the Perceived Stress Scale (PSS-10) questionnaire. Blood pressure was measured using a mercury sphygmomanometer. Data were analyzed by Chi-square test and Logistic Regression.Results and Discussion: There was a significant relationship between nutritional status, sleep duration, and stress levels with blood pressure. The results of the multivariate analysis showed that the shift nurses with overweight (obesity) nutritional status are at a risk of having disorder 1.97 times, the shift nurses with sleep duration < 6 hours are at risk of having disorder 3.78 times and shift nurses with intermediate stress level at risk of having disorder 2.08 times with enhancement blood pressure.Conclusion: There is a relationship between nutritional status, sleep duration and stress level with blood pressure. Sleep duration mostly influences the blood pressure.International Journal of Human and Health Sciences Vol. 04 No. 01 January’20 Page : 55-59

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Does diurnal variation in blood pressure exist in CAPD patients?Reply by authors

Nephrology Dialysis Transplantation ◽

10.1093/ndt/9.11.1699a ◽

1994 ◽

Keyword(s):

Blood Pressure ◽

Diurnal Variation

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Altered Diurnal Variation of Blood Pressure in Eldery Subjects with Decreased Activity of Daily Living and Impaired Cognitive Function.

Hypertension Research ◽

10.1291/hypres.24.655 ◽

2001 ◽

Vol 24 (6) ◽

pp. 655-661 ◽

Cited By ~ 13

Author(s):

Yusuke OHYA ◽

Toshio OHTSUBO ◽

Takuya TSUCHIHASHI ◽

Kimika ETO ◽

Tsuneaki SADANAGA ◽

...

Keyword(s):

Blood Pressure ◽

Cognitive Function ◽

Diurnal Variation ◽

Daily Living ◽

Activity Of Daily Living ◽

Impaired Cognitive Function

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α1-Adrenoreceptor activity does not explain lower morning endothelial-dependent, flow-mediated dilation in humans

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00042.2011 ◽

2011 ◽

Vol 300 (6) ◽

pp. R1437-R1442 ◽

Cited By ~ 13

Author(s):

Helen Jones ◽

Nia C. S. Lewis ◽

Daniel J. Green ◽

Philip N. Ainslie ◽

Samuel J. E. Lucas ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Shear Rate ◽

Diurnal Variation ◽

Sympathetic Nerve ◽

Sympathetic Nerve Activity ◽

Time Of Day ◽

Flow Mediated Dilation ◽

Nerve Activity ◽

Dependent Flow

Early morning reduction in endothelium-dependent, flow-mediated dilation (FMD) may contribute to the high incidence of sudden cardiac death at this time of day. The mechanisms underpinning diurnal variation in FMD are unclear, but potentially relate to a circadian rhythm in sympathetic nerve activity. We hypothesized that blockade of α1-mediated sympathetic nerve activity would act to attenuate the diurnal variation in FMD. In a randomized and placebo-controlled design, we measured brachial artery FMD in 12 participants (mean age = 26 yr, SD = 3) at 0600 and 1600 after ingestion of an α1-blocker (prazosin, 1 mg/20 kg body mass) or placebo. Arterial diameter and shear rate were assessed using edge-detection software. Heart rate and blood pressure were also measured. Data were analyzed using linear mixed modeling. Following placebo, FMD was 8 ± 2% in the morning compared with 10 ± 3% in the afternoon ( P = 0.04). Blockade with prazosin led to a slight but nonsignificant increase in morning FMD ( P = 0.24) and a significant ( P = 0.04) decrease in afternoon FMD, resulting in no diurnal variation ( P = 0.20). Shear rate did not differ in the morning or afternoon under either condition ( P > 0.23). Blood pressure was lower following prazosin compared with placebo ( P < 0.02), an effect that was similar at both times of day ( P > 0.34). Heart rate and norepinephrine levels were higher in the afternoon following prazosin. These data indicate that α1-adrenoreceptor activity does not explain lower morning endothelium-dependent FMD.

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