Ventilatory decline after hypoxia and hypercapnia  is not different between healthy young men and women

The gradual decay in ventilation after removal of a respiratory stimulus has been proposed to protect against cyclic breathing disorders such as obstructive sleep apnea (OSA). The male predominance of OSA, and the increased incidence of OSA in women after menopause, indicates that the respiratory-stimulating effect of progesterone may provide protection against OSA by altering the rate of poststimulus ventilatory decline (PSVD). It was therefore hypothesized that PSVD is longer in premenopausal women than in men and is longer in the luteal menstrual phase compared with the follicular phase. PSVD was measured in 12 men and in 11 women at both their luteal and follicular phases, after cessation of isocapnic hypoxia and normoxic hypercapnia. PSVD was compared between genders and between women in the luteal and follicular phases by repeated-measures ANOVA. There were no significant differences in PSVD between any of the groups after either respiratory stimulus. This suggests that the higher occurrence of OSA in men does not reflect an underlying gender difference in PSVD and implies the increased prevalence of OSA in women after menopause is not representative of an effect of progesterone on PSVD.

Download Full-text

Facial attractiveness and lip morphology of Caucasian women

Anthropological Review ◽

10.2478/anre-2018-0035 ◽

2018 ◽

Vol 81 (4) ◽

pp. 404-413 ◽

Cited By ~ 1

Author(s):

Zdzisław Lewandowski ◽

Dariusz P. Danel

Keyword(s):

Empirical Study ◽

Repeated Measures ◽

Facial Attractiveness ◽

Facial Features ◽

Sexually Dimorphic ◽

Men And Women ◽

Repeated Measures Anova ◽

Adult Men ◽

Caucasian Women

Abstract Human lips are one of the most sexually dimorphic facial features. Although lip morphology is considered particularly important for female facial attractiveness no systematic empirical study has been conducted in this respect. This study aimed to investigate a relationship between female Caucasian facial attractiveness and their lip morphology. Two series of morphologically average composite portraits with digitally increased and decreased lip width and height measurements were assessed by adult men and women. Results were analysed using repeated measures ANOVA. When compared to the average lip shape both a decrease and an increase in lip width were associated with lower female facial attractiveness. A systematic increase in lip height from the lowest values to the highest, was associated with an increase in attractiveness scores. Attractiveness assessments of men and women did not differ significantly. The results show that perception of lip attractiveness may be intersexually congruent and that a variation in lip morphology may significantly affect female facial attractiveness.

Download Full-text

Comparison of effects of sustained isocapnic hypoxia on ventilation in men and women

Journal of Applied Physiology ◽

10.1152/jappl.1997.83.2.599 ◽

1997 ◽

Vol 83 (2) ◽

pp. 599-607 ◽

Cited By ~ 19

Author(s):

Dimitar Sajkov ◽

Alister Neill ◽

Nicholas A. Saunders ◽

R. Douglas McEvoy

Keyword(s):

Menstrual Cycle ◽

Minute Ventilation ◽

Premenopausal Women ◽

Follicular Phase ◽

Inspiratory Time ◽

Men And Women ◽

Ventilatory Responses ◽

Reduced Frequency ◽

Normal Men ◽

Respiratory Depressant

Sajkov, Dimitar, Alister Neill, Nicholas A. Saunders, and R. Douglas McEvoy. Comparison of the effects of sustained isocapnic hypoxia on ventilation in men and women. J. Appl. Physiol. 83(2): 599–607, 1997.—Sleep-related respiratory disturbances are more common in men than in premenopausal women. This might, in part, be due to different susceptibilities to the respiratory depressant effects of hypoxia. Therefore, we compared ventilation during 10 min of baseline room-air breathing and 20-min sustained isocapnic hypoxia (fractional inspired O2 = 11%, arterial saturation of O2 ≈ 80%) followed by 10 min of breathing 100% O2 in 10 normal men and in 10 women in the follicular phase of the menstrual cycle. Control measurements were made during two transitions from room air (10 min) to 100% O2 (10 min) and averaged. Inspired minute ventilation (V˙i) after 2 min of hypoxia was the same in men and women [131 ± 6.1% baseline for men, 136 ± 7.7% baseline for women; not significant (NS)] and declined to the same level after 20 min (115 ± 5.0% baseline for men, 116 ± 6.6% baseline for women; NS) associated with a similar decline in inspiratory time and tidal volume. Breathing frequency did not change.V˙i decreased transiently during subsequent 100% O2 breathing in both men and women, associated with reduced frequency and duty cycle and increased expiratory time. The fall inV˙i was significantly greater than that observed during control hyperoxia experiments in men but not in women. We conclude that ventilatory responses to sustained isocapnic hypoxia do not differ between awake healthy men and women in the follicular phase of their menstrual cycle. However, after termination of isocapnic hypoxia, men appear to depress their ventilation to a greater degree than women.

Download Full-text

Long-term facilitation of ventilation is not present during wakefulness in healthy men or women

Journal of Applied Physiology ◽

10.1152/japplphysiol.00135.2002 ◽

2002 ◽

Vol 93 (6) ◽

pp. 2129-2136 ◽

Cited By ~ 52

Author(s):

A. S. Jordan ◽

P. G. Catcheside ◽

F. J. O'Donoghue ◽

R. D. McEvoy

Keyword(s):

Repeated Measures ◽

Human Subjects ◽

Minute Ventilation ◽

Upper Airway ◽

Menstrual Phase ◽

Healthy Human ◽

Dilator Muscle ◽

Obstructive Sleep ◽

Long Term Facilitation

Obstructive sleep apnea (OSA) is more common in men than in women for reasons that are unclear. The stability of the respiratory controller has been proposed to be important in OSA pathogenesis and may be involved in the gender difference in prevalence. Repetitive hypoxia elicits a progressive rise in ventilation in animals [long-term facilitation (LTF)]. There is uncertainty whether LTF occurs in humans, but if present it may stabilize respiration and possibly also the upper airway. This study was conducted to determine 1) whether LTF exists during wakefulness in healthy human subjects and, if so, whether it is more pronounced in women than men and 2) whether inspiratory pump and upper airway dilator muscle activities are affected differently by repetitive hypoxia. Twelve healthy young men and ten women in the luteal menstrual phase were fitted with a nasal mask and intramuscular genioglossal EMG (EMGgg) recording electrodes. After 5 min of rest, subjects were exposed to ten 2-min isocapnic hypoxic periods (∼9% O2 in N2, arterial O2 saturation ∼80%) separated by 2 min of room air. Inspired minute ventilation (V˙i) and peak inspiratory EMGgg activity were averaged over 30-s intervals, and respiratory data were compared between genders during and after repetitive hypoxia by using ANOVA for repeated measures. V˙i during recovery from repetitive hypoxia was not different from the resting level and not different between genders. There was no facilitation of EMGgg activity during or after repetitive hypoxia. EMGgg activity was reduced below baseline during recovery from repetitive hypoxia in women. In conclusion, we have found no evidence of LTF of ventilation or upper airway dilator muscle activity in healthy subjects during wakefulness.

Download Full-text

Prenatal diethylstilbestrol exposure and reproductive hormones in premenopausal women

Journal of Developmental Origins of Health and Disease ◽

10.1017/s2040174415000082 ◽

2015 ◽

Vol 6 (3) ◽

pp. 208-216 ◽

Cited By ~ 9

Author(s):

L. A. Wise ◽

R. Troisi ◽

E. E. Hatch ◽

L. J. Titus ◽

K. J. Rothman ◽

...

Keyword(s):

Repeated Measures ◽

Premenopausal Women ◽

Reproductive Hormones ◽

Follicular Phase ◽

Inhibin B ◽

Reproductive Age ◽

Endogenous Hormones ◽

Reproductive Disorders ◽

Early Follicular Phase

Diethylstilbestrol (DES), a synthetic estrogen widely prescribed to pregnant women in the mid-1900s, is a potent endocrine disruptor. Prenatal DES exposure has been associated with reproductive disorders in women, but little is known about its effects on endogenous hormones. We assessed the association between prenatal DES exposure and reproductive hormones among participants from the Harvard Study of Moods and Cycles (HSMC), a longitudinal study of premenopausal women aged 36–45 years from Massachusetts (1995–1999). Prenatal DES exposure was reported at baseline (43 DES exposed and 782 unexposed). Early follicular-phase concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and estradiol were measured at baseline and every 6 months during 36 months of follow-up. Inhibin B concentrations were measured through 18 months. We used multivariable logistic and repeated-measures linear regression to estimate odds ratios (OR) and percent differences in mean hormone values (β), respectively, comparing DES exposed with unexposed women, adjusted for potential confounders. DES-exposed women had lower mean concentrations of estradiol (pg/ml) (β=−15.6%, 95% confidence interval (CI): −26.5%, −3.2%) and inhibin B (pg/ml) (β=−20.3%, CI: −35.1%, −2.3%), and higher mean concentrations of FSH (IU/I) (β=12.2%, CI: −1.5%, 27.9%) and LH (IU/I) (β=10.4%, CI: −7.2%, 31.3%), than unexposed women. ORs for the association of DES with maximum FSH>10 IU/I and minimum inhibin B<45 pg/ml – indicators of low ovarian reserve – were 1.90 (CI: 0.86, 4.22) and 4.00 (CI: 0.88–18.1), respectively. Prenatal DES exposure was associated with variation in concentrations of FSH, estradiol and inhibin B among women of late reproductive age.

Download Full-text

Respiratory system loop gain in normal men and women measured with proportional-assist ventilation

Journal of Applied Physiology ◽

10.1152/japplphysiol.00585.2002 ◽

2003 ◽

Vol 94 (1) ◽

pp. 205-212 ◽

Cited By ~ 36

Author(s):

Andrew Wellman ◽

Atul Malhotra ◽

Robert B. Fogel ◽

Jill K. Edwards ◽

Karen Schory ◽

...

Keyword(s):

Tidal Volume ◽

Amplification Factor ◽

Respiratory Control ◽

Periodic Breathing ◽

Loop Gain ◽

Proportional Assist Ventilation ◽

Men And Women ◽

Male Predominance ◽

Obstructive Sleep ◽

Normal Men

We hypothesized that increased chemical control instability (CCI) in men could partially explain the male predominance in obstructive sleep apnea (OSA). CCI was assessed by sequentially increasing respiratory control system loop gain (LG) with proportional-assist ventilation (PAV) in 10 men (age 24–48 yr) and 9 women (age 22–36 yr) until periodic breathing or awakening occurred. Women were studied in both the follicular and luteal phases of the menstrual cycle. The amount by which PAV amplified LG was quantified from the tidal volume amplification factor [(VtAF) assisted tidal volume/unassisted tidal volume]. LG was calculated as the inverse of the VtAF occurring at the assist level immediately preceding the emergence of periodic breathing (when LG × VtAF = 1). Only 1 of 10 men and 2 of 9 women developed periodic breathing with PAV. The rest were resistant to periodic breathing despite moderately high levels of PAV amplification. We conclude that LG is low in the majority of normal men and women and that higher volume amplification factors are needed to determine whether gender differences exist in this low range.

Download Full-text

Selected Contribution: Genioglossus muscle activity at rest and in response to brief hypoxia in healthy men and women

Journal of Applied Physiology ◽

10.1152/japplphysiol.00461.2001 ◽

2002 ◽

Vol 92 (1) ◽

pp. 410-417 ◽

Cited By ~ 36

Author(s):

A. S. Jordan ◽

P. G. Catcheside ◽

F. J. O'Donoghue ◽

N. A. Saunders ◽

R. D. McEvoy

Keyword(s):

Gender Difference ◽

Repeated Measures ◽

Neural Control ◽

Minute Ventilation ◽

Upper Airway ◽

Men And Women ◽

Healthy Men ◽

Pharyngeal Airway ◽

Obstructive Sleep ◽

The Relationship

10.1152/japplphysiol.00461.2001.—Obstructive sleep apnea (OSA) is more common in men than in women for reasons that are not clearly understood. An underlying difference between men and women in the respiratory-related neural control of upper airway dilator muscles has been suggested as a possible reason for the gender difference. We have compared three aspects of upper airway dilator muscle function in healthy men and women: 1) resting inspiratory genioglossus electromyogram (EMGgg) activity, 2) the respiratory EMGgg “afterdischarge” after a brief hypoxic stimulus, and 3) the relationship between the EMGgg and pharyngeal airway pressure. Inspired minute ventilation (V˙i), epiglottic pressure (Pepi), and EMGgg and diaphragm EMG (EMGdi) activity were measured in 24 subjects (12 men, 12 women in the luteal menstrual phase) and were compared between genders while lying supine awake. Every 7–8 min over 2 h, subjects were exposed to 45-s periods of isocapnic hypoxia (9% O2 in N2) that were abruptly terminated with one breath of 100% O2. The relationship between Pepi and EMGgg activity was also compared between genders. The results of 117 trials with satisfactory end-tidal Pco 2 control and no sighs or swallows are reported. There was no gender difference in the resting level of peak inspiratory EMGgg [3.7 ± 0.8 (women) vs. 3.2 ± 0.6% maximal activity (men)]. Repeated-measures ANOVA showed no gender or gender-by-time interaction effect between men and women inV˙i or EMGgg or EMGdi activity during or after the hypoxic stimulus. The relationship between Pepi and EMGgg was not different between men (slope −0.63 ± 0.20) and women (slope −0.69 ± 0.33). These results do not support the hypothesis that the higher prevalence of OSA in men is related to an underlying gender difference in respiratory neural control of upper airway dilator muscles.

Download Full-text

The effects of pre-sleep consumption of casein protein on next-morning measures of RMR and appetite compared between sedentary pre- and postmenopausal women

British Journal Of Nutrition ◽

10.1017/s0007114520001506 ◽

2020 ◽

Vol 125 (2) ◽

pp. 121-128

Author(s):

Christopher M. Schattinger ◽

J. T. Leonard ◽

C. L. Pappas ◽

M. J. Ormsbee ◽

L. B. Panton

Keyword(s):

Body Composition ◽

Postmenopausal Women ◽

Repeated Measures ◽

Analogue Scale ◽

Controlled Trial ◽

Premenopausal Women ◽

Double Blind ◽

Repeated Measures Anova ◽

Casein Protein ◽

One Way Anova

AbstractThe purpose of the present study was to compare next-morning responses of RMR and appetite to pre-sleep consumption of casein protein (CP) in pre- and postmenopausal women. The study was a randomised, crossover, double-blind, placebo-controlled trial. Seven sedentary premenopausal (age: 19·9 (sd 1·2) years; BMI: 23·1 (sd 2·6) kg/m2) and seven sedentary postmenopausal (age: 56·4 (sd 4·9) years; BMI: 26·3 (sd 3·5) kg/m2) women participated. During visit one, anthropometrics and body composition were measured. Following visit one, subjects consumed either CP (25 g) or placebo (PL) ≥2 h after their last meal and ≤30 min prior to sleep on the night before visits two and three. Visits two and three occurred ≥1 week after visit one and were 48 h apart. During visits two and three, RMR (VO2), RER and appetite were measured via indirect calorimetry and visual analogue scale, respectively. Anthropometrics and body composition were analysed by one-way ANOVA. RMR and measures of appetite were analysed using a 2 × 2 (menopause status × CP/PL) repeated-measures ANOVA. Significance was accepted at P ≤ 0·05. RMR was significantly lower in postmenopausal compared with premenopausal women under both conditions (P = 0·003). When consumed pre-sleep CP did not alter RMR, RER or appetite compared with PL when assessed next morning in pre- and postmenopausal women. These data contribute to growing evidence that pre-sleep consumption of protein is not harmful to next-morning metabolism or appetite. In addition, these data demonstrate that menopause may not alter next-morning RMR, RER or appetite after pre-sleep consumption of CP.

Download Full-text

0658 The Effect of Text Message Reminders on Positive Airway Pressure Adherence in Veterans With Obstructive Sleep Apnea

SLEEP ◽

10.1093/sleep/zsaa056.654 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A251-A251

Author(s):

Q Al Saleh ◽

D Kim ◽

K Jordan ◽

M Balish ◽

L Kataria

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Repeated Measures ◽

Airway Pressure ◽

Positive Airway Pressure ◽

Text Message ◽

Text Messages ◽

Repeated Measures Anova ◽

Obstructive Sleep

Abstract Introduction Adherence to positive airway pressure (PAP) therapy continues to be a challenge. The main objective of this study was to determine whether mobile text-message reminders increased PAP adherence in veterans with obstructive sleep apnea. Methods This is a retrospective study of 25 patients with poor adherence to PAP therapy who used the Veterans Affairs ANNIE app to receive nightly mobile text message reminders. PAP adherence was measured at baseline, 1,and 3 months. A one-way repeated measures ANOVA was used to compare the effect of time on PAP adherence, specifically the percentage of overall days used and percentage use >4 hours. A two-way repeated measures ANOVA without replication was used to determine the effects of AHI severity and time on PAP adherence. Results Our sample demographics included a mean age of 59 ±12 years, mean BMI of 33.5% ±5.4, and mean AHI of 26.3 ±25.4. The mean PAP overall percentage use and mean use >4 hours respectively were 32% ± 27 and 18% ± 19 at baseline, 66% ± 27 and 45% ± 30 at 1 month, and 54% ±32 and 37% ± 30 at 3 months. After three months of receiving nightly text-message reminders, there was a statistically significant effect of time on percentage overall PAP use, F (2, 48)=21.54, p=2.10E-07, as well as in the percentage PAP use >4 hours, F (2, 48)=22.05, p=1.61E-07. A two-way repeated measures ANOVA without replication yielded a main effect of the interaction of time with PAP adherence, F (2, 48)=22, p=<0.0001. AHI severity was not a significant factor. Conclusion Nightly text message reminders significantly improved PAP adherence from baseline to 3 months. Though PAP adherence was not optimal, it doubled initially in our sample. Further studies are warranted to determine how text-messages can be used long term to improve adherence. Support Nil

Download Full-text

The Effects of the Barbell Hip Thrust on Post-Activation Performance Enhancement of Change of Direction Speed in College-Aged Men and Women

Sports ◽

10.3390/sports8120151 ◽

2020 ◽

Vol 8 (12) ◽

pp. 151

Author(s):

Ashley J. Orjalo ◽

Samuel J. Callaghan ◽

Robert G. Lockie

Keyword(s):

Repeated Measures ◽

Performance Enhancement ◽

Relative Strength ◽

Men And Women ◽

Repeated Measures Anova ◽

Change Of Direction ◽

Speed Test ◽

Main Effect ◽

Partial Correlations ◽

And Performance

This study investigated whether the barbell hip thrust (BHT) enhanced change-of-direction (COD) speed measured by the 505 COD speed test. Forty recreationally trained individuals completed three sessions. Session 1 included one-repetition maximum (1RM) BHT testing to measure absolute and relative strength. Sessions 2 and 3 involved two counter-balanced conditioning activities (CAs): 3 sets × 5 repetitions of the BHT at 85% 1RM and a control condition (CC; 6 min rest). The 505 COD speed test was performed 5 and 2.5 min pre-CA, and 4, 8, 12, and 16 min post-CA in each session. A 2 × 5 repeated-measures ANOVA (p < 0.05) calculated performance changes across time post-CA. A 2 × 2 repeated-measures ANOVA analyzed best potentiated performance. Partial correlations controlling for sex calculated relationships between the 1RM BHT and 505 COD speed test percent potentiation. There was a significant main effect for time (p < 0.001), but not for condition (p = 0.271) or condition × time (p = 0.295). There were no significant correlations between 1RM BHT and potentiation. The 85% 1RM BHT did potentiate the 505 4–16 min post-CA but no more than the CC. Nonetheless, a heavy BHT could be programmed prior to COD drills as COD speed could be potentiated and performance improved in men and women.

Download Full-text

One Size Fits All?

Methodology ◽

10.1027/1614-2241/a000044 ◽

2012 ◽

Vol 8 (1) ◽

pp. 23-38 ◽

Cited By ~ 1

Author(s):

Manuel C. Voelkle ◽

Patrick E. McKnight

Keyword(s):

Repeated Measures ◽

Structural Equation ◽

Type I Error ◽

Equation Modeling ◽

Type I ◽

Finite Sample ◽

Traditional Methods ◽

Repeated Measures Anova ◽

Special Cases ◽

Latent Curve

The use of latent curve models (LCMs) has increased almost exponentially during the last decade. Oftentimes, researchers regard LCM as a “new” method to analyze change with little attention paid to the fact that the technique was originally introduced as an “alternative to standard repeated measures ANOVA and first-order auto-regressive methods” (Meredith & Tisak, 1990, p. 107). In the first part of the paper, this close relationship is reviewed, and it is demonstrated how “traditional” methods, such as the repeated measures ANOVA, and MANOVA, can be formulated as LCMs. Given that latent curve modeling is essentially a large-sample technique, compared to “traditional” finite-sample approaches, the second part of the paper addresses the question to what degree the more flexible LCMs can actually replace some of the older tests by means of a Monte-Carlo simulation. In addition, a structural equation modeling alternative to Mauchly’s (1940) test of sphericity is explored. Although “traditional” methods may be expressed as special cases of more general LCMs, we found the equivalence holds only asymptotically. For practical purposes, however, no approach always outperformed the other alternatives in terms of power and type I error, so the best method to be used depends on the situation. We provide detailed recommendations of when to use which method.

Download Full-text