Effect of desogestrel-containing oral contraceptives on vascular reactivity and catecholamine levels

A Systematic Review and Meta-Analysis Examining Whether Changing Ovarian Sex Steroid Hormone Levels Influence Cerebrovascular Function

Sex differences in cerebrovascular disease rates indicate a possible role for ovarian sex steroid hormones in cerebrovascular function. To synthesise and identify knowledge gaps, a systematic review and meta-analysis was conducted to assess how ovarian sex steroid hormone changes across the lifespan affect cerebrovascular function in women. Three databases (EMBASE, MEDLINE and Web of Science) were systematically searched for studies on adult cerebrovascular function and ovarian sex steroid hormones. Forty-five studies met pre-defined inclusion criteria. Studied hormone groups included hormone replacement therapy (HRT; n = 17), pregnancy (n = 12), menstrual cycle (n = 7), menopause (n = 5), oral contraception (n = 2), and ovarian hyperstimulation (n = 2). Outcome measures included pulsatility index (PI), cerebral blood flow/velocity (CBF), resistance index (RI), cerebral autoregulation, and cerebrovascular reactivity. Meta-analysis was carried out on HRT studies. PI significantly decreased [−0.05, 95% CI: (−0.10, −0.01); p = 0.01] in post-menopausal women undergoing HRT compared to post-menopausal women who were not, though there was considerable heterogeneity (I² = 96.8%). No effects of HRT were seen in CBF (p = 0.24) or RI (p = 0.77). This review indicates that HRT improves PI in post-menopausal women. However, there remains insufficient evidence to determine how changing ovarian sex steroid hormone levels affects cerebrovascular function in women during other hormonal phases (e.g., pregnancy, oral contraception).

Differential Responses of Urinary Epinephrine and Norepinephrine to 24-h Shift-Work Stressor in Physicians

Multiple stressors, including 24-h-shifts characterise the working environment of physicians, influencing well-being, health and performance. We aimed to evaluate the effect of the stressor 24-h-shift on the adrenal medullary and sympathoneural system in physicians with the hypothesis that shift work might have different impacts on both systems. Twenty-two physicians collected two 12-h-urine samples ("daytime" and "nighttime") during a 24-h shift ("on-duty") and on a free weekend ("off-duty"), respectively. Urinary excretion rates per m² body surface area were assessed for the catecholamines epinephrine, norepinephrine and their respective free O-methylated metabolites metanephrine and normetanephrine by LC-MS/MS-analysis. The stressor provoked differential responses of epinephrine and norepinephrine. Epinephrine excretion rates showed significant increases from off to on duty. The largest proportional change (off-duty to on-duty) for epinephrine was observed for nighttime (205%), the increase for daytime was 84%. An increase in norepinephrine from off to on duty was only visible for nighttime collections. For the catecholamine metabolites, normetanephrine paralleled norepinephrine and exhibited an increase in excretion from off to on duty during nighttime collections of 53% whereas there was no change during daytime collections (3%). In conclusion: Whilst the 24-h-shift-work stressor in physicians activates the sympatho-adrenomedullary system, represented by epinephrine, the sympathoneural response through norepinephrine reflects mainly an ambulatory position during working hours.

Associations between oral contraceptive use and risks of hypertension and prehypertension in a cross-sectional study of Korean women

BACKGROUND

The effect of commonly used oral contraceptives (OCs) on blood pressure is still unclear. The aim of this study was to examine the relationship between OCs use and blood pressure and the prevalence of hypertension in a population-based sample of Korean women.

METHODS

A cross-sectional study was conducted using data from 3356 participants aged 35-55 years collected in the 2007-2009 Korea National Health and Nutrition Examination Surveys. OC use and demographic characteristics were obtained from participants using a questionnaire, and blood pressure was measured with a mercury sphygmomanometer.

RESULTS

Longer duration of OC use was positively associated with increasing levels of systolic blood pressure and diastolic blood pressure (p for trend <0.001). After adjusting for covariates, the odds ratio (OR) of hypertension was significantly increased in longer-term (>24 months) OC users (OR 1.96; 95% confidence interval (CI) 1.03-3.73) compared with those who had never used OCs. Additionally, use of OCs >24 months was associated with increased odds of prehypertension (adjusted OR 2.23; 95% CI 1.28-3.90) and hypertension or prehypertension (adjusted OR 2.13; 95% CI 1.37-3.32).

CONCLUSION

This study found a statistically significant association between OC use and blood pressure or hypertension among Korean women.

Influence of third-generation oral contraceptives on the complexity analysis and symbolic dynamics of heart rate variability

OBJECTIVE

To evaluate the influence of oral contraceptives (OCs) containing 20 μg ethinylestradiol (EE) and 150 μg gestodene (GEST) on the autonomic modulation of heart rate (HR) in women.

METHODS

One-hundred and fifty-five women aged 24 ± 2 years were divided into four groups according to their physical activity and the use or not of an OC: active-OC, active-non-OC (NOC), sedentary-OC, and sedentary-NOC. The heart rate was registered in real time based on the electrocardiogram signal for 15 minutes, in the supine-position. The heart rate variability (HRV) was analysed using Shannon's entropy (SE), conditional entropy (complexity index [CInd] and normalised CInd [NCI]), and symbolic analysis (0V%, 1V%, 2LV%, and 2ULV%). For statistical analysis the Kruskal-Wallis test with Dunn post hoc and the Wilcoxon test (p < 0.05 was considered significant) were applied.

RESULTS

Treatment with this COC caused no significant changes in SE, CInd, NCI, or symbolic analysis in either active or sedentary groups. Active groups presented higher values for SE and 2ULV%, and lower values for 0V% when compared to sedentary groups (p < 0.05).

CONCLUSION

HRV patterns differed depending on life style; the non-linear method applied was highly reliable for identifying these changes. The use of OCs containing 20 μg EE and 150 μg GEST does not influence HR autonomic modulation.

Plasma dopamine in workers exposed to urban stressor

The aim of this study is to evaluate if the occupational exposure to urban stressor could cause alterations in dopamine (DA) plasma levels and related diseases in traffic police officers compared to a control group. After excluding subjects with principal confounding factors, 306 traffic police officers (139 female and 167 male) and 301 controls (134 female and 167 male) were included in the study. In traffic police officers, mean DA values were significantly higher compared with controls (P = 0.006 and P = 0.000 in male and female, respectively). The distribution of DA values in traffic police officers and controls was significant (P = 0.000 and P = 0.000 in male and female, respectively). The number of male traffic police officers with a positive response to the questionnaire's items concerning anxiety, depression and panic attacks was higher than controls, though not significant (7.2% traffic police officers versus 4.2% controls). This difference was also not significant in female traffic police officers compared with controls. According to our previous researches on other neuro-immune-endocrine parameters, DA could be used as an early biological marker, valuable for the group to be employed in occupational sets, even before the onset of pathology.

[Catecholamine response to the Wingate test in untrained women]

Supramaximal exercises are well known to induce a severe stress on the adrenal medulla and nervous sympathetic system. This stress induces increased plasma catecholamines concentrations. The responses of catecholamines to supramaximal exercises in women are still not well characterized and have been studied mostly in trained subjects. Hence the aim of the present study was to evaluate plasma catecholamine responses to a Wingate test in young and untrained women (n = 6) and men (n = 7). Venous plasma catecholamine concentrations were determined by HPLC, at rest, at the end of the warm-up and of the exercise, and during recovery (5, 10, 20, and 30 mn). Our results failed to show any significant difference in resting catecholamine concentrations ([A]p: 0.41 +/- 0.05 vs. 0.45 +/- 0.05 nmol. L-1; [NA]p: 3.28 +/- 0.68 vs. 2.58 +/- 0.26 nmol.L-1), kinetics, and maximal plasma catecholamine concentrations (Amax: 4.47 +/- 1.08 vs. 3.31 +/- 0.63 nmol.L-1; NAmax: 18.05 +/- 1.11 vs. 14.01 +/- 2.02 nmol.L-1) in response to the Wingate test between women and men, respectively. The Amax/NAmax ratio used as an index of adrenal medulla sensitivity to sympathetic input was also similar between genders. In conclusion, this study was able to demonstrate, in untrained subjects, that gender did not alder the sympatho-adrenergic response induced by a severe stress.

Sympathoadrenal response of postmenopausal women prior and during prolonged administration of estradiol

OBJECTIVE

Cardiovascular disease seems to increase after the menopause and is thought to be reduced by estrogen replacement therapy. Among the many studies which have tried to define the multifactorial mechanisms of estrogens cardiovascular prevention, very few have focused on their possible modulation of adrenergic activity. In the present study we investigated whether prolonged estradiol replacement via transdermal patches is able to modulate cardiovascular and adrenergic responses to stimuli.

METHODS

Baseline and responses to a cold stimulus and to the upright position of catecholamines (epinephrine and norepinephrine), heart rate, systolic and diastolic blood pressure were investigated in 15 healthy volunteer postmenopausal women both prior to and after 2 months of treatment with patches rated to deliver 50 microg/day of estradiol.

RESULTS

Basal norepinephrine levels (P<0.005), as well as their integrated responses to the cold stimulus (P<0.02) were lower during estradiol. By contrast, responses of norepinephrine to the upright test, as well as basal and responses to stimuli of epinephrine and circulatory parameters were not different before and during estradiol.

CONCLUSIONS

Estradiol replacement at low doses significantly decreases overall sympathetic output, both in basal conditions and under specific stimuli. These effects whether maintained or magnified in the long term may play a role in the prevention of the postmenopausal cardiovascular risk.