scholarly journals Directional sensitivity of the cerebral pressure-flow relationship in middle and posterior cerebral arteries using the repeated squat-stand model: within-day reproducibility and impact of diurnal variation in young healthy men and women

2021 ◽  
Author(s):  
Lawrence Labrecque ◽  
Joel S. Burma ◽  
Marc-Antoine Roy ◽  
Jonathan D. Smirl ◽  
Patrice Brassard
Keyword(s):  
Sex Differences ◽  
Diurnal Variation ◽  
Cerebral Arteries ◽  
Intraclass Correlation ◽  
Time Of Day ◽  
Directional Sensitivity ◽  
Pressure Flow ◽  
Men And Women ◽  
Healthy Men ◽  
Time Points

We recently employed repeated squat-stands (RSS) to quantify directional sensitivity of the cerebral-pressure flow relationship (i.e. hysteresis) using a novel metric. Within-day reproducibility and diurnal variation impacts of this metric are unknown. We evaluated this metric for: 1) within-day reproducibility and the extent diurnal variation has in middle (MCA; ∆MCAvT/∆MAPT) and posterior cerebral arteries (PCA; ∆PCAvT/∆MAPT); 2) sex differences. Absolute (∆MCAvT/∆MAPT ; ∆PCAvT/∆MAPT) and relative (%MCAvT/%MAPT, %PCAvT/%MAPT) metrics were calculated at seven time-points (08:00-17:00) in 18 participants (8 women; 24 ± 3 yrs) using the minimum-to-maximum MCAv/PCAv and MAP for each RSS at 0.05 Hz and 0.10 Hz. Reproducibility was evaluated with intraclass correlation coefficient (ICC). For all metrics, reproducibility was good (0.75-0.90) to excellent (>0.90). The metric in both arteries was impacted by MAP direction at 0.10 Hz (all p < 0.024). Time-of-day influenced ∆MCAvT/∆MAPT (0.05 Hz: p = 0.0028; 0.10 Hz: p = 0.0009), %MCAvT/%MAPT (0.05 Hz: p = 0.035; 0.10 Hz: p = 0.0087), and ∆PCAvT/∆MAPT (0.05 Hz: p = 0.0236). Sex differences in the MCA (p = 0.0028) vanished in relative terms and was absent in the PCA. These findings demonstrate within-day reproducibility of this metric in both arteries. Moreover, hysteresis is not impacted by sex.

Reproducibility and diurnal variation of the directional sensitivity of the cerebral pressure-flow relationship in men and women

2021 ◽  
Author(s):  
Lawrence Labrecque ◽  
Joel S. Burma ◽  
Marc-Antoine Roy ◽  
Jonathan David Smirl ◽  
Patrice Brassard
Keyword(s):  
Sex Differences ◽  
Diurnal Variation ◽  
Cerebral Arteries ◽  
Intraclass Correlation ◽  
Time Of Day ◽  
Effect Sizes ◽  
Directional Sensitivity ◽  
Pressure Flow ◽  
Biological Sex ◽  
Relative Metric

The cerebral pressure-flow relationship has directional sensitivity, meaning the augmentation in cerebral blood flow is attenuated when mean arterial pressure (MAP) increases vs MAP decreases. We employed repeated squat-stands (RSS) to quantify it using a novel metric. However, its within-day reproducibility and the impacts of diurnal variation and biological sex are unknown. Study aims were to evaluate this metric for: 1) within-day reproducibility and diurnal variation in middle (MCA; ∆MCAvT/∆MAPT) and posterior cerebral arteries (PCA; ∆PCAvT/∆MAPT); 2) sex differences. ∆MCAvT/∆MAPT and ∆PCAvT/∆MAPT were calculated at seven time-points (08:00-17:00) in 18 participants (8 women; 24 ± 3 yrs) using the minimum-to-maximum MCAv or PCAv and MAP for each RSS at 0.05 Hz and 0.10 Hz. Relative metric values were also calculated (%MCAvT/%MAPT, %PCAvT/%MAPT). Intraclass correlation coefficient (ICC) evaluated reproducibility, which was good (0.75-0.90) to excellent (>0.90). Time-of-day impacted ∆MCAvT/∆MAPT (0.05 Hz: p = 0.002; 0.10 Hz: p = 0.001), %MCAvT/%MAPT (0.05 Hz: p = 0.035; 0.10 Hz: p = 0.009), and ∆PCAvT/∆MAPT (0.05 Hz: p = 0.024), albeit with small/negligible effect sizes. MAP direction impacted both arteries' metric at 0.10 Hz (all p < 0.024). Sex differences in the MCA only (p = 0.003) vanished when reported in relative terms. These findings demonstrate this metric is reproducible throughout the day in the MCA and PCA and is not impacted by biological sex.

Are there sex differences in visceral sensitivity in young healthy men and women?

2019 ◽  
Vol 31 (9) ◽  
Author(s):  
Adriane Icenhour ◽  
Franziska Labrenz ◽  
Till Roderigo ◽  
Carsten Siebert ◽  
Sigrid Elsenbruch ◽  
...  
Keyword(s):  
Sex Differences ◽  
Visceral Sensitivity ◽  
Men And Women ◽  
Healthy Men

scholarly journals Sex-Differences in Discontinuation of Statin Treatment in Cancer Patients the Year before Death

2021 ◽  
Vol 14 (4) ◽  
pp. 368
Author(s):  
Gabriella Frisk ◽  
Helena Bergström ◽  
Maria Helde Frankling ◽  
Linda Björkhem-Bergman
Keyword(s):  
Sex Differences ◽  
Advanced Cancer ◽  
Cardiovascular Events ◽  
Statin Treatment ◽  
Men And Women ◽  
Time Points ◽  
Disease Trajectory ◽  
Significant Difference ◽  
History Of ◽  
One Year

Statin treatment is often terminated in patients with advanced cancer but guidelines for statin discontinuation are still lacking. The aim of this study was to investigate sex-differences in time-points of statin discontinuation in patients with advanced cancer. Medical records from 1535 deceased patients enrolled at a Palliative Home Care Unit were reviewed. A total of 149 patients (42 women and 107 men) who were diagnosed with cancer, and were treated with statins one year before death, were identified. Statin treatment was terminated earlier in women than in men, 3.0 months prior to death (IQR 0.88–7.25) as compared to 1.5 months (IQR 0.5–4.0) (p < 0.05), respectively. In a longitudinal analysis there was a significant difference between men and women still on statin treatment at all studied time-points, 9, 6, and 3 months before death (p < 0.05), where women terminated statin treatment earlier in the disease trajectory. Baseline demographics were similar between the sexes except that more men than women had a history of previous cardiovascular events (p < 0.01). However, neither the indication for statin treatment, i.e., primary prevention versus secondary prevention, nor age could explain the sex-difference in statin discontinuation. There was no difference in cardiovascular events or mortality between men and women after statin discontinuation.

scholarly journals Sex differences in the cardiovascular consequences of the inspiratory muscle metaboreflex

2016 ◽  
Vol 311 (3) ◽  
pp. R574-R581 ◽  
Author(s):  
Joshua R. Smith ◽  
Ryan M. Broxterman ◽  
Shane M. Hammer ◽  
Andrew M. Alexander ◽  
Kaylin D. Didier ◽  
...  
Keyword(s):  
Sex Differences ◽  
Premenopausal Women ◽  
Inspiratory Muscle ◽  
Breathing Frequency ◽  
Limb Blood Flow ◽  
Men And Women ◽  
Muscle Metaboreflex ◽  
Healthy Men ◽  
Mouth Pressure ◽  
Resistive Breathing

It is currently unknown whether sex differences exist in the cardiovascular consequences of the inspiratory muscle metaboreflex. We hypothesized that the activation of the inspiratory muscle metaboreflex will lead to less of an increase in mean arterial pressure (MAP) and limb vascular resistance (LVR) and less of a decrease in limb blood flow (Q̇L) in women compared with men. Twenty healthy men ( n = 10, 23 ± 2 yr) and women ( n = 10, 22 ± 3 yr) were recruited for this study. Subjects performed inspiratory resistive breathing tasks (IRBTs) at 2% or 65% of their maximal inspiratory mouth pressure (PIMAX). During the IRBTs, the breathing frequency was 20 breaths/min with a 50% duty cycle. At rest and during the IRBTs, MAP was measured via automated oscillometry, Q̇L was measured via Doppler ultrasound, and LVR was calculated. EMG was recorded on the leg to ensure no muscle contraction occurred. The 65% IRBT led to attenuated increases ( P < 0.01) from baseline in women compared with men for MAP (W: 7.3 ± 2.0 mmHg; M: 11.1 ± 5.0 mmHg) and LVR (W: 17.7% ± 14.0%; M: 47.9 ± 21.0%), as well as less of a decrease ( P < 0.01) in Q̇L (W: −7.5 ± 9.9%; M: −23.3 ± 10.2%). These sex differences in MAP, Q̇L, and LVR were still present in a subset of subjects matched for PIMAX. The 2% IRBT resulted in no significant changes in MAP, Q̇L, or LVR across time or between men and women. These data indicate premenopausal women exhibit an attenuated inspiratory muscle metaboreflex compared with age-matched men.

scholarly journals Empathy levels decline and sex differences in medicine students from the Caribbean

2021 ◽  
Vol 69 (4) ◽  
pp. e86227
Author(s):  
Eugenia Smirna González-Díaz ◽  
Maria Guadalupe Silva-Vetri ◽  
Patricia Díaz-Calzadilla ◽  
Aracelis Calzadilla-Núñez ◽  
Alejandro Reyes-Reyes ◽  
...  
Keyword(s):  
Sex Differences ◽  
Medical Students ◽  
Medical Training ◽  
Intraclass Correlation ◽  
Regression Equations ◽  
Undergraduate Medical Students ◽  
Cronbach’S Alpha ◽  
Cross Sectional ◽  
Men And Women ◽  
Cronbach's Alpha

Introduction: Empathy is an important trait in the training of medical students, as it has been shown to improve the doctor-patient relationship. Objective: To evaluate empathy levels decline and possible sex differences in empathy levels in undergraduate medical students from the Universidad Central del Este, Dominican Republic. Materials and methods: Exploratory cross-sectional study. A Spanish version of the Jefferson Scale of Empathy for Medical Students (S-version) Scale was administered in September 2018 to 1144 1st-year to 5th-year medical students (887 women and 257 men). The reliability of the data was verified using the Cronbach's alpha and the intraclass correlation coefficient (ICC). Data were analyzed using a generalized linear equation model (Type III) and the Wald chi-squared test was used to determine differences in overall empathy levels and the mean scores obtained in each of its three components according to the year of medical training and to sex. Results. Cronbach's alpha was satisfactory (0.839) and the ICC was 0.834 (F=5.68; p=0.005). Variability of the estimated curves in relation to empathic behavior by course (year of medical training) and sex was observed using linear and non-linear regression equations: between courses: Wald χ2==115.6; p=0.0001, and between men and women: χ2 of Wald =12.85; p=0.001. Conclusions. There were sex differences regarding empathy levels in the study population; besides, a decline in empathy levels (overall empathy and Compassionate Care component in men, and Walking in the Patient’s Shoes component in men and women) was also observed as students progressed in their medical training. The behavior of these data raises questions regarding the need to determine the factors causing these differences and the decline in empathy levels.

Threshold of airway response to inhaled methacholine in healthy men and women

1984 ◽  
Vol 56 (1) ◽  
pp. 129-132 ◽  
Author(s):  
N. Zamel
Keyword(s):  
Sex Differences ◽  
Age Distribution ◽  
Flow Volume ◽  
Men And Women ◽  
Healthy Men ◽  
Doubling Dose ◽  
Full Inspiration ◽  
Airway Response

Threshold of airway response to inhaled methacholine was determined using maximum expiratory partial flow-volume curves in 21 men and 36 women with similar age distribution, all of them healthy nonsmokers. Mean threshold was on average 1.3 doubling dose lower in women than men. There were no sex differences in the increase of maximum expiratory flows after a full inspiration when the airways were constricted by methacholine.

SEX DIFFERENCES BETWEEN HEALTHY MEN AND WOMEN IN PITUITARY LH-RESPONSE TO MULTIPLE STIMULATIONS WITH SYNTHETIC LH-RH

1975 ◽  
Vol 80 (1_Suppla) ◽  
pp. S22
Author(s):  
A. Römmler ◽  
S. Baumgarten ◽  
J. Hammerstein
Keyword(s):  
Sex Differences ◽  
Men And Women ◽  
Healthy Men ◽  
Lh Rh

Sex Differences in Cardiovascular Reactivity

2009 ◽  
Vol 23 (2) ◽  
pp. 77-84 ◽  
Author(s):  
Matthew C. Whited ◽  
Kevin T. Larkin
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Sex Differences ◽  
Gender Roles ◽  
Cardiovascular Reactivity ◽  
Task Type ◽  
Conflict Task ◽  
Men And Women ◽  
Conflicting Evidence ◽  
Blood Pressure Responses

Sex differences in cardiovascular reactivity to stress are well documented, with some studies showing women having greater heart rate responses than men, and men having greater blood pressure responses than women, while other studies show conflicting evidence. Few studies have attended to the gender relevance of tasks employed in these studies. This study investigated cardiovascular reactivity to two interpersonal stressors consistent with different gender roles to determine whether response differences exist between men and women. A total of 26 men and 31 women were assigned to either a traditional male-oriented task that involved interpersonal conflict (Conflict Task) or a traditional female-oriented task that involved comforting another person (Comfort Task). Results demonstrated that women exhibited greater heart rate reactions than men independent of the task type, and that men did not display a higher reactivity than women on any measure. These findings indicate that sex of participant was more important than gender relevance of the task in eliciting sex differences in cardiovascular responding.

The Relationship of Compliance with Coping Strategies and Self-Esteem

2003 ◽  
Vol 19 (2) ◽  
pp. 117-123 ◽  
Author(s):  
Gisli H. Gudjonsson ◽  
Jon Fridrik Sigurdsson
Keyword(s):  
Sex Differences ◽  
Coping Strategies ◽  
Multiple Regression ◽  
Sex Difference ◽  
Test Scores ◽  
Self Esteem ◽  
Stressful Situation ◽  
Men And Women ◽  
Relationship Of ◽  
The Relationship

Summary: The Gudjonsson Compliance Scale (GCS), the COPE Scale, and the Rosenberg Self-Esteem Scale were administered to 212 men and 212 women. Multiple regression of the test scores showed that low self-esteem and denial coping were the best predictors of compliance in both men and women. Significant sex differences emerged on all three scales, with women having lower self-esteem than men, being more compliant, and using different coping strategies when confronted with a stressful situation. The sex difference in compliance was mediated by differences in self-esteem between men and women.

Sex Differences in Time Production Revisited

2012 ◽  
Vol 33 (1) ◽  
pp. 35-42 ◽  
Author(s):  
Joseph Glicksohn ◽  
Yamit Hadad
Keyword(s):  
Sex Differences ◽  
Individual Differences ◽  
Sex Difference ◽  
Absolute Error ◽  
Internal Clock ◽  
Target Duration ◽  
Log P ◽  
Men And Women ◽  
Time Production ◽  
T Score

Individual differences in time production should indicate differences in the rate of functioning of an internal clock, assuming the existence of such a clock. And sex differences in time production should reflect a difference in the rate of functioning of that clock between men and women. One way of approaching the data is to compute individual regressions of produced duration (P) on target duration (T), after log transformation, and to derive estimates for the intercept and the slope. One could investigate a sex difference by comparing these estimates for men and women; one could also contrast them by looking at mean log(P). Using such indices, we found a sex difference in time production, female participants having a relatively faster internal clock, making shorter time productions, and having a smaller exponent. The question is whether a sex difference in time production would be found using other methods for analyzing the data: (1) the P/T ratio; (2) an absolute discrepancy (|P-T|) score; and (3) an absolute error (|P-T|/T) score. For the P/T ratio, female participants have a lower mean ratio in comparison to the male participants. In contrast, the |P-T| and |P-T|/T indices seem to be seriously compromised by wide individual differences.

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