The Effect of Low-dose Combined Oral Contraceptive Pills on Brachial Artery Endothelial Function and Common Carotid Artery Intima–Media Thickness

Oral contraceptive pill phase alters mechanisms contributing to cutaneous microvascular function in response to local heating

The purpose of this study was to investigate the effect of oral contraceptive pill (OCP) phase on in vivo microvascular endothelium-dependent vasodilation and contributions of nitric oxide (NO), cyclooxygenase (COX), and endothelial-derived hyperpolarizing factors (EDHFs). Participants completed two experimental visits in random order, during the 1) low and 2) high hormone phase of the OCP cycle. Endothelium-dependent dilation was assessed in the cutaneous microvasculature via local heating at four intradermal microdialysis sites treated with: 1) lactated Ringer's (control), 2) 10 mM ketorolac (Keto, COX inhibitor), 3) 50 mM tetraethylammonium (TEA, calcium-activated potassium channel inhibitor), and 4) 10 mM ketorolac + 50 mM TEA (Keto + TEA). Perfusion of 20 mM Nω-nitro-l-arginine methyl ester (l-NAME) at each site was used to quantify the l-NAME-sensitive component of dilation, suggesting NO contribution. There was no effect of OCP phase on endothelium-dependent dilation (P = 0.75) or the l-NAME-sensitive component of the response (P = 0.09, d = 0.7) at control sites. Inhibition of COX increased baseline blood flow regardless of OCP phase (all P < 0.01). Control and Keto sites elicited greater endothelium-dependent dilation than TEA and Keto + TEA sites in both phases (all P < 0.0001). During the low hormone phase, the l-NAME-sensitive component was greater at control compared with TEA sites (P < 0.01). During the high hormone phase, the l-NAME-sensitive component was greater at Keto compared with TEA sites (P < 0.01). Within-participant differences between control and Keto sites support a phase-dependent restraint of NO activity via COX pathways (P = 0.01). These findings demonstrate that the OCP phase affects underlying mechanistic pathways contributing to cutaneous microvascular endothelial function.NEW & NOTEWORTHY This study investigates the effect of OCP phase on in vivo microvascular endothelium-dependent vasodilation and explores underlying mechanisms. Present findings suggest OCP phase does not affect overall microvascular endothelium-dependent dilation but does affect the underlying mechanisms. In women using OCP, there is a robust reliance on EDHF pathways and the COX pathway moderates basal microvascular blood flow and demonstrates a phase-dependent restraint of the NO pathway.

Vascular health and exercise in females throughout the lifespan: Exploring puberty, pregnancy and menopause

This narrative review highlights the impact of exercise on vascular health in females over the lifespan with an emphasis on puberty, pregnancy and menopause. These events encompass substantial changes in sex hormone levels, particularly oestrogens and progesterone. They are also accompanied by distinct adaptations of the central, peripheral and cerebral vasculature. Regular exercise is an effective mechanism to reduce vascular risk in females of all ages, especially for those at higher risk for vascular disorders. However, there are large variabilities in the vascular adaptations to exercise in females that may be related to circulating sex hormone levels. In addition, exogenous hormones, such as oral contraceptives taken after puberty or hormonal replacement therapy taken to mitigate symptoms of menopause, may interact with exercise-induced changes in vascular function. We highlight how more research is needed to understand the optimal exercise interventions to promote vascular health in females across the lifespan, especially during times of hormonal transition.

Modulation of Vascular Health by Hormonal Contraceptives and Exercise in Young Women: Using the FITT Principles Methodological Framework

Cardiovascular health is governed by responses of the heart and vasculature to stimuli, including exercise and synthetic hormones in hormonal contraception. In this review, we draw similarities between research examining the effects of exercise training and hormonal contraception on vascular health, aligned using FITT principles (frequency, intensity, type, and time) as a methodological framework, and outline future directions for research.

Menstrual and oral contraceptive pill cycles minimally influence vascular function and associated cellular regulation in premenopausal females

Historical exclusion of females in research has been, in part, due to the perceived influence of natural menstrual (NAT) and oral contraceptive pill (OCP) cycles on vascular outcomes. NAT and OCP cycle phases may influence brachial artery (BA) endothelial function, however, findings are mixed. Minimal research has examined arterial stiffness, smooth muscle, and lower limb endothelial function. The purpose of this study was to investigate the influence of NAT and OCP cycles on cardiovascular outcomes and cellular regulation. Forty-nine premenopausal females (n = 17 NAT, n = 17 second generation OCP, n = 15 third generation OCP) participated in two randomized order visits in the low (LH, early follicular/placebo) and high (HH, midluteal/active) hormone cycle phases. BA and superficial femoral artery (SFA) endothelial function [flow-mediated dilation (FMD) test], smooth muscle function (nitroglycerine-mediated dilation test), and carotid and peripheral (pulse wave velocity) arterial stiffness were assessed. Cultured female human endothelial cells were exposed to participant serum for 24 h to examine endothelial nitric oxide synthase (eNOS) and estrogen receptor-α (ERα) protein content. BA FMD was elevated in the HH vs. LH phase, regardless of group (HH, 7.7 ± 3.5%; LH, 7.0 ± 3.3%; P = 0.02); however, allometric scaling for baseline diameter resulted in no phase effect (HH, 7.6 ± 2.6%; LH, 7.1 ± 2.6%; P = 0.052, d = 0.35). SFA FMD, BA, and SFA smooth muscle function, arterial stiffness, and eNOS and ERα protein content were unaffected. NAT and OCP phases examined have minimal influence on vascular outcomes and ERα-eNOS pathway, apart from a small effect on BA endothelial function partially explained by differences in baseline artery diameter. NEW & NOTEWORTHY Comprehensive evaluation of the cardiovascular system in naturally cycling and second and third generation OCP users indicates no major influence of hormonal phases examined on endothelial function and smooth muscle function in the arteries of the upper and lower limbs, arterial stiffness, or underlying cellular mechanisms. Study findings challenge the historical exclusion of female participants due to potentially confounding hormonal cycles; researchers are encouraged to consider the hormonal environment in future study design.

The influence of oral contraceptives on the exercise pressor reflex in the upper and lower body

Previous research has demonstrated that oral contraceptive (OC) users have enhanced cardiorespiratory responses to arm metaboreflex activation (i.e., postexercise circulatory occlusion, PECO) and attenuated pressor responses to leg passive movement (PM) compared to non-OC users (NOC). We investigated the cardiorespiratory responses to arm or leg metaboreflex and mechanoreflex activation in 32 women (OC, n = 16; NOC, n = 16) performing four trials: 40% handgrip or 80% plantarflexion followed by PECO and arm or leg PM. OC and NOC increased mean arterial pressure (MAP) similarly during handgrip, plantarflexion and arm/leg PECO compared to baseline. Despite increased ventilation (VE) during exercise, none of the women exhibited higher VE during arm or leg PECO. OC and NOC similarly increased MAP and VE during arm or leg PM compared to baseline. Therefore, OC and NOC were similar across pressor and ventilatory responses to arm or leg metaboreflex and mechanoreflex activation. However, some differences due to OC may have been masked by disparities in muscle strength. Since women increase VE during exercise, we suggest that while women do not display a ventilatory response to metaboreflex activation (perhaps due to not reaching a theoretical metabolite threshold to stimulate VE), the mechanoreflex may drive VE during exercise in women.

Hormonal intrauterine devices and heat exchange during exercise

Synthetic progestins in oral contraceptives are thought to blunt heat dissipation by reducing skin blood flow and sweating. However, whether progestin-releasing intrauterine devices (IUDs) modulate heat loss during exercise-heat stress is unknown. We used direct calorimetry to measure whole-body total (dry + evaporative) heat loss in young, physically active women (mean (SD); aged 24 (4) years,V ̇ O 2 peak ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{peak}}}}$ 39.3 (5.3) ml/kg/min) with (IUD; n = 19) and without (Control; n = 17) IUDs in the follicular and luteal phases of the menstrual cycle during light- and moderate-intensity exercise at fixed rates of heat production (∼175 and ∼275 W/m2 ) in 30°C, ∼21% relative humidity. Between-group and -phase differences were evaluated using traditional hypothesis testing and statistical equivalence testing within pre-determined bounds (±11 W/m2 ; difference required to elicit a ±0.3°C difference in core temperature over 1 h) in each exercise bout. Whole-body total heat loss was statistically equivalent between groups within ±11 W m-2 (IUD-Control [90% CIs]; Light: -2 [-8, 5] W/m2 , P = 0.007; Moderate: 0 [-6, 6] W/m2 , P = 0.002), as were dry and evaporative heat loss (P ≤ 0.023), except for evaporative heat loss during moderate-intensity exercise (equivalence: P = 0.063, difference: P = 0.647). Whole-body total and evaporative heat loss were not different between phases (P ≥ 0.267), but dry heat loss was 3 [95% CIs: 1, 5] W/m2 greater in the luteal phase (P ≤ 0.022). Despite this, all whole-body heat loss outcomes were equivalent between phases (P ≤ 0.003). These findings expand our understanding of the factors that modulate heat exchange in women and provide valuable mechanistic insight of the role of endogenous and exogenous female sex hormones in thermoregulation. KEY POINTS: Progestin released by hormonal intrauterine devices (IUDs) may negatively impact heat dissipation during exercise by blunting skin blood flow and sweating. However, the influence of IUDs on thermoregulation has not previously been assessed. We used direct calorimetry to show that IUD users and non-users display statistically equivalent whole-body dry and evaporative heat loss, body heat storage and oesophageal temperature during moderate- and high-intensity exercise in a warm, dry environment, indicating that IUDs do not appear to compromise exercise thermoregulation. However, within IUD users and non-users, dry heat loss was increased and body heat storage and oesophageal temperature were reduced in the luteal compared to the follicular phase of the menstrual cycle, though these effects were small and unlikely to be practically meaningful. Together, these findings expand our understanding of the factors that modulate heat exchange in women and have important practical implications for the design of future studies of exercise thermoregulation.

High-fat diet promotes coagulation and endothelial activation in Sprague Dawley rats: Short-term effects of combined oral contraceptives

BACKGROUND

Combined oral contraceptives (COCs), use in individuals are associated with increased risk of thrombotic events. This highlights the significance of assessing the impact of COC on promoting coagulation and endothelial activation in high-fat diet (HFD)-fed Sprague Dawley rats.

METHODS

Twenty (20) five-weeks-old female Sprague Dawley rats weighing between 150 and 200g were subjected to both LFD and HFD-feeding for 8-weeks to determine its influence on basic metabolic status, hemostatic profile, hemodynamic parameters (blood pressure and heart rate), as well as selected biomarkers of coagulation (tissue factor and D-dimer) and endothelial activation (Von Willebrand factor and nitric oxide). Thereafter HFD-fed animals were treated with receive high dose combined oral contraceptive (HCOC) and low dose combine oral contraceptive (LCOC) for 6 weeks.

RESULTS

Our results showed that beyond weight gain, HFD-feeding was associated with hyperglycemia, increased mean arterial pressure, and reduced nitric oxide levels when compared with LFD group (p<0.05). Interestingly, treatment with high dose of COC for 6-weeks did not significantly alter atherothrombotic markers (p>0.05). However, this study is not without limitation as regulation of these markers remains to be confirmed within the cardiac tissues or endothelial cells of these animals.

CONCLUSION

HFD-feeding orchestrate the concomitant release of pro-coagulants and endothelial activation markers in rats leading to haemostatic imbalance and endothelial dysfunction. Short-term treatment with COC shows no detrimental effects in these HFD-fed rats. Although in terms of clinical relevance, our findings depict the notion that the risk of CVD in association with COC may depend on the dosage and duration of use among other factors especially in certain conditions. However, additional studies are required to confirm these findings, especially long-term effects of this treatment within the cardiac tissues or endothelial cells of these animals in certain conditions relating to postmenopausal state.

Investigating cardiovascular risk in premenopausal women on oral contraceptives: Systematic review with meta-analysis

Background

The use of oral contraceptives (OCs) is associated with an increased risk of cardiovascular events such as arterial and venous thrombosis (VTE). Cardiovascular diseases (CVDs) are the leading cause of death worldwide, with low- and middle-income nations accounting for over three-quarter of CVD deaths. The aim of this systematic review is to provide a comprehensive synthesis of the available evidence on the link between OC use and CVD risk in premenopausal women and to further assess the role of geographic disparities in the reported prevalence of CVD risk in women on OCs.

Methods

A comprehensive search of databases such as MEDLINE, Academic Search Complete, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Health Source: Nursing/Academic Edition was conducted, right from the inception to the present, by using the EBSCOhost search engine. The Cochrane Central Register of Clinical trials (CENTRAL) was also searched to augment relevant sources of information. OpenGrey, which is a repository of information providing open access to bibliographical references, was searched and the reference list of the selected studies was also scanned. The potential risk of bias of the included studies was assessed using the modified Downs and Black checklist. Data analysis was performed using the Review Manager (RevMan) version 5.3.

Results

We included 25 studies that comprised 3,245 participants, of which 1,605 (49.5%) are OC users, while 1,640 (50.5%) are non-OC users. A total of 15 studies were included for meta-analysis, and the overall pooled estimates suggested a significant increase in the traditional cardiovascular risk variables [standardized mean difference (SMD) = 0.73, (0.46, 0.99) (Z = 5.41, p < 0.001)] and little to no difference in endothelial activation among OC users when compared with non-OC users [SMD = -0.11, (-0.81, 0.60) (Z = 0.30, p = 0.76)]. Europe [SMD = 0.03, (-0.21, 0.27), (Z = 0.25 p = 0.88)] had the least effect size, while North America had the highest effect size [SMD = 1.86, (-0.31, 4.04), (Z = 1.68 p = 0.09)] for CVD risk in OC users when compared with non-OC users.

Conclusion

The use of OCs suggests a significant increase in the prevalence of traditional cardiovascular risk variables with little to no difference in the risk of endothelial dysfunction when compared with non-OC users, and the magnitude of CVD risks varies across different geographical regions.

Registration and protocol

This systematic review was registered in the international prospective register of systematic reviews (PROSPERO) under the registration number: CRD42020216169.

Investigating the risks of cardiovascular disease among premenopausal women using oral contraceptive: a protocol for a systematic review and meta-analysis

INTRODUCTION

The use of oral contraceptives (OCs) is linked to an increased risk of cardiovascular diseases (CVDs) in women of reproductive age. CVD remain one of the top causes of death worldwide, with at least three-quarters of deaths occurring in low-income and middle-income nations. The impact of various types of combined oral contraceptive (COC) on several modifiable risk factors associated with CVDs in premenopausal women is inconsistent regardless of genetic mutations. The aim of this systematic review will be to provide a comprehensive synthesis of the available evidence on the impact of COC usage on modifiable risk factors associated with CVDs and assess ethnic and geographic disparities in the reported prevalence of CVD.

METHODS AND ANALYSIS

This systematic review protocol was prepared in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses Protocols 2015 statement. An extensive search on the Embase, MEDLINE and Cochrane Library will be conducted from inception until. Two reviewers will independently screen for eligible studies using a predefined criterion. The risk of bias and quality of included studies will be assessed using the modified Downs and Black's checklist. Whereas the overall quality of included studies will be assessed using the Grading of Recommendations, Assessment, Development and Evaluation assessment tool.

ETHICS AND DISSEMINATION

This is a review of existing studies and will not require ethical approval. The findings will be disseminated through peer-reviewed publication. The use of OC and the risk of CVDs including arterial and venous thrombosis remain a major concern among women of reproductive age. Thus, given the impact of COCs on the risk variables linked with CVDs, this review may provide an insight and assistance during COC use.

PROSPERO REGISTRATION NUMBER

CRD42020216169.

Biological Assessment of the NO-Dependent Endothelial Function

Nitric oxide (NO) is implicated in numerous physiological processes, including vascular homeostasis. Reduced NO bioavailability is a hallmark of endothelial dysfunction, a prequel to many cardiovascular diseases. Biomarkers of an early NO-dependent endothelial dysfunction obtained from routine venous blood sampling would be of great interest but are currently lacking. The direct measurement of circulating NO remains a challenge due by its high reactivity and short half-life. The current techniques measure stable products from the NO signaling pathway or metabolic end products of NO that do not accurately represent its bioavailability and, therefore, endothelial function per se. In this review, we will concentrate on an original technique of low temperature electron paramagnetic resonance spectroscopy capable to directly measure the 5-α-coordinated heme nitrosyl-hemoglobin in the T (tense) state (5-α-nitrosyl-hemoglobin or HbNO) obtained from fresh venous human erythrocytes. In humans, HbNO reflects the bioavailability of NO formed in the vasculature from vascular endothelial NOS or exogenous NO donors with minor contribution from erythrocyte NOS. The HbNO signal is directly correlated with the vascular endothelial function and inversely correlated with vascular oxidative stress. Pilot studies support the validity of HbNO measurements both for the detection of endothelial dysfunction in asymptomatic subjects and for the monitoring of such dysfunction in patients with known cardiovascular disease. The impact of therapies or the severity of diseases such as COVID-19 infection involving the endothelium could also be monitored and their incumbent risk of complications better predicted through serial measurements of HbNO.

Modeling hormonal contraception in female rats: A framework for studies in behavioral neurobiology

Research on hormonal contraceptives (HC) in animal models is lacking, and as a result, so is our understanding of the impact of HC on the brain and behavior. Here, we provide a review of the pharmacology of HC, as well as the methodology and best practices for designing a model of HC in female rats. We outline specific methodological considerations regarding dosing, route of administration, exposure time/timing, and selecting a control group. We also provide a framework outlining important levels of analysis for thinking about the impact of HC on behavioral and neurobiological outcomes. The purpose of this review is to equip researchers with foundational knowledge, and some basic elements of experimental design for future studies investigating the impact of HC on the brain and behavior of female rats.

Oral contraceptives and stroke: Foes or friends

Incidents of strokes are increased in young women relative to young men, suggesting that oral contraceptive (OC) use is one of the causes of stroke among young women. Long-term exposures to the varying combinations of estrogen and progestogen found in OCs affect blood clotting, lipid and lipoprotein metabolism, endothelial function, and de novo synthesis of neurosteroids, especially brain-derived 17β-estradiol. The latter is essential for neuroprotection, memory, sexual differentiation, synaptic transmission, and behavior. Deleterious effects of OCs may be exacerbated due to comorbidities like polycystic ovary syndrome, sickle cell anemia, COVID-19, exposures to endocrine disrupting chemicals, and conventional or electronic cigarette smoking. The goal of the current review is to revisit the available literature regarding the impact of OC use on stroke, to explain possible underlying mechanisms, and to identify gaps in our understanding to promote future research to reduce and cure stroke in OC users.

Interleukin-6 is higher in naturally menstruating women compared with oral contraceptive pill users during the low-hormone phase

Endogenous sex hormone concentrations vary between healthy naturally menstruating (non-OCP) and oral contraceptive pill-using (OCP) women, as well as across cycles. The aim of this study was to investigate potential differences in concentrations of inflammatory cytokine interleukin-6 (IL-6) and vasoconstrictive substance endothelin-1 (ET-1) and measures of vascular function among relatively lower- and higher-hormone phases of non-OCP and OCP women. Concentrations of estrogen, progesterone, IL-6, and ET-1 and measures of vascular function were collected in 22 women (22 ± 1 yr, OCP: n = 12) during the early follicular (EF, ≤5 days of menstruation onset) and early luteal (EL, 4 ± 2 days postovulation) phases of non-OCP subjects and were compared to the placebo pill (PP, ≤5 days of PP onset) and active pill (AP, ≤5 days of highest-dose AP) phases of OCP subjects. Vascular function was assessed via brachial artery flow-mediated dilation (%FMD). Concentrations of endogenous estrogen and progesterone were higher in the EL phase compared with the EF phase of non-OCP (P = 0.01) but were similar between phases of OCP (P > 0.05). IL-6 was higher in non-OCP during the EF phase compared with the EL phase (P = 0.03) as well as compared with OCP during the PP phase (P = 0.002) but was similar between groups during the EL and AP phases, respectively (P > 0.05). Concentrations of ET-1 and measures of %FMD were similar between groups and unaffected by phase (P > 0.05). Thus, there exists variation in inflammation between young, healthy non-OCP and OCP women during the lower-hormone phase, despite similarities in vascular function and concentrations of ET-1 between groups and phases.NEW & NOTEWORTHY We demonstrate that despite having similar macrovascular function and concentrations of the vasoconstrictive substance endothelin-1 (ET-1) healthy naturally menstruating women display higher concentrations of circulating IL-6 during the lower-hormone phase of their menstrual cycle compared with 1) the higher-hormone phase of their menstrual cycle and 2) the lower-hormone phase of healthy women using oral contraceptive pills.

Hormonally Active Contraceptives Part I: Risks Acknowledged and Unacknowledged

Hormonal contraceptives have been on the market for over fifty years and, while their formulations have changed, the basic mechanism of action has remained the same. During this time, numerous studies have been performed documenting side effects, some of which appear over time, some within weeks or months, but all can have a serious impact on health and quality of life. An effort was made to perform a series of comprehensive literature surveys to better understand immediate and long-term side effects of these agents. The results of this literature review uncovered a number of potential side effects, some of which are acknowledged and many of which are not noted in the prescribing information for these agents. Among the unacknowledged side effects are: an increased risk of HIV transmission for depot medroxyprogesterone acetate (DMPA), and for combination contraceptives breast cancer, cervical cancer, Crohn's disease, ulcerative colitis, systemic lupus erythematosus, depression, mood disorders and suicides (especially among women twenty-five years of age and younger, in the first six months of use), multiple sclerosis, interstitial cystitis, female sexual dysfunction, osteoporotic bone fractures (especially for progesterone-only contraceptives), and fatty weight gain. Misleading prescribing information regarding cardiovascular and thrombotic risks are also noted. Women seeking birth control have a right to be informed and educated about risk avoidance through the use of effective nonhormonal methods like fertility awareness methods. In one case-that of DMPA-the increased risk of HIV acquisition has been conclusively demonstrated to be both real and unique to this drug. Considering the availability of numerous alternatives, there is no justification for the continued marketing of DMPA to the public.

SUMMARY

We reviewed the effect of hormonal contraceptives on women's health. A number of potential side effects were noted including increased risks of breast cancer, cervical cancer, inflammatory bowel  disease, lupus, multiple sclerosis, cystitis, bone fractures, depression, mood disorders and suicides,  fatty weight gain, and female sexual dysfunction.  With the long-acting injectable contraceptives there is an increased risk of getting HIV.  Misleading prescribing information regarding the risks of heart attacks, strokes and blood clotting problems were also noted. Women seeking birth control have a right to know about how to avoid these risks by using effective hormone-free Fertility Awareness Methods.

Arterial Stiffness and Hemodynamics in Young Women: The Effects of Oral Contraceptive Intake and Physical Habits

Oral contraceptive (OC) intake seems to be associated with increased central hemodynamics and arterial stiffness. Conversely, physical activity (PA) is known to induce benefits on vascular structure and function, suggesting that the negative effects of the OC pill could be counterbalanced by regular PA. The aim of this cross-sectional study was to determine (1) whether OC intake in young women is associated with higher values of hemodynamic parameters and arterial stiffness and (2) whether these negative effects could be counterbalanced by regular physical activity. Forty-nine young healthy women (21.9 years ± 2.1) were recruited and divided into 4 groups, depending on their hormonal status (OC users: OC+ or non-OC users: OC−) and their physical habits (active/inactive). Assessments of central hemodynamics (central blood pressure, Aix75) and pulse wave velocity (PWV) were performed using applanation tonometry. cBP was higher in OC+ vs. OC−, while PWV was similar between these two groups. No interaction between physical activity and hormonal status was observed for any of these variables. Nevertheless, PWV was lower in young active women compared with age-matched inactive women, suggesting that the positive effect of regular physical exercise on the cardiovascular system is already visible in the first years of women’s adulthood, whatever the hormonal status.

Vascular Endothelial Function Assessed by Flow-Mediated Vasodilatation in Young Adults Born Very Preterm or With Extremely Low Birthweight: A Regional Cohort Study

Background: Preterm birth and low birthweight have been associated with increased risk of cardiovascular disease in young adults. Endothelial dysfunction is established as an early marker for development of atherosclerotic cardiovascular disease. Previous studies of endothelial function in young adults born very preterm or with extremely low birthweight have, however, shown diverging results. Objective: We aimed to evaluate the risk of cardiovascular disease as measured by vascular endothelial function in young adults born very preterm (<29 weeks of gestation) or with extremely low birthweight (<1,000 g), compared with term-born controls. Methods: This study included 50 young adults born very preterm or with extremely low birthweight and 49 term-born controls born in Norway in the periods 1982-1985, 1991-1992, and 1999-2000 at mean age 28 (±6) years. The endothelial function was assessed by ultrasound measured flow-mediated dilatation (FMD) of the right brachial artery. The arterial diameter was measured at baseline, after release of 5 min of occlusion, and after sublingual administration of nitroglycerine. FMD was reported as absolute and percentage diameter change from baseline and relative to nitroglycerine-induced dilatation. Results: The participants were mainly normal weight non-smokers, without hypertension, diabetes, or established cardiovascular disease. The cases and controls had mean blood pressure 112/71 (SD 12/9) and 112/69 (SD 11/8) mmHg, body mass index 24.0 (SD 4.2) and 24.4 (SD 4.5) kg/m², and HbA1c 32.7 (SD 2.5) and 33.0 (SD 2.6) mmol/mol, respectively. For both groups, 4 (8%) were smokers. Mean FMD for the adults born very preterm or with extremely low birthweight was 0.17 mm (95% CI 0.14, 0.21) vs. 0.24 mm (95% CI 0.20, 0.28) for the controls (p = 0.01), corresponding to a percentage increase of 5.4% (95% CI 4.2, 6.6) and 7.6% (95% CI 6.2, 8.9), respectively (p = 0.02). The FMD relative to maximal nitroglycerine-induced dilatation was 20% and 31%, respectively (p = 0.001). Conclusions: Young adults born very preterm or with extremely low birthweight have significantly lower FMD compared with the term-born controls suggesting an increased risk of cardiovascular disease.

Combined oral contraceptives modify the effect of smoking on inflammatory cellular indexes and endothelial function in healthy subjects

Little information is available on the influence of sex in combination with smoking habits and combined oral contraceptives (COC) use on cellular inflammatory indexes such as neutrophil/lymphocyte ratio (NLR), derived NRL (dNLR), platelet/lymphocyte ratio (PLR), monocyte/lymphocyte ratio (MLR), mean platelet volume/platelet count (MPV/PLT), aggregate inflammation systemic index (AISI), and systemic inflammation response index (SIRI), which are cost-effective biomarkers to assessing inflammation. Therefore, the effect of COC was studied alone or in association with smoking and compared with results from healthy COC-free women and men. Furthermore, the association of cellular inflammatory indexes with endothelial function (arginine (Arg), asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA) and lipid peroxidation (malondialdehyde MDA) biomarkers was evaluated. Blood was collected for hematological and biochemical analysis, which were used to calculate PLR, NLR, dNLR, MLR, MPV/PLT, AISI, and SIRI. Serum samples were assayed for Arg, ADMA, SDMA, and MDA. Monocytes, MLR, SIRI, and MPV/PLT were higher in men, while PLT count was higher in women. COC use increased lymphocytes and lowered PLR and MLR. Smoking reduced sexually divergent parameters, especially in COC users: smoking and non-smoking COC-free women displayed six divergent parameters, while COC users displayed only two (monocytes and MPV). In addition, COC affected endothelial function, reducing ADMA and Arg. Moreover, COC-free women had lower Arg levels than men. In conclusion, COC use strongly influence the effects of tobacco smoking, which are sex and parameter specific. Further, these data stress that COC use and smoking attitude select different cohorts indicating that sex and gender studies need intersectionality.

Female Sex Hormone Effects on the Vasculature: Considering the Validity of Restricting Study Inclusion to Low-Hormone Phases

Many studies of vascular function limit the testing of premenopausal female participants to periods when female sex hormones, either endogenous or exogenous, are at their lowest concentration. This practice, when not part of the specific research question, may limit data surrounding the predominant physiological state of premenopausal females and pose a threat to external validity. In this Perspective, we briefly review the literature on the effect of female sex hormones on vascular function and discuss when limiting experimental testing to a certain phase of the menstrual cycle (MC) or oral contraceptive (OC) use may be appropriate. The goal of this Perspective is to open a dialog that may enhance data validity and the overall understanding of vascular function in premenopausal females.

Influence of hormonal contraceptives on peripheral vascular function and structure in premenopausal females: a review

Hormonal contraceptives are one of the most widely used prescriptions for premenopausal women worldwide. Although the risk of venous and arterial cardiovascular events (e.g., deep vein thrombosis, arterial clotting) with hormonal contraceptives, specifically oral contraceptive pills, has been established, the literature on early risk indicators, such as peripheral vascular structure and function has yet to be consolidated. The purpose of this review is to summarize literature examining the impact of different hormonal contraceptives on vascular function and structure, including consideration of phasic differences within a contraceptive cycle, and to propose future directions for research. It is evident that hormonal contraceptive use appears to impact both macrovascular and microvascular endothelial function, with phasic differences in some contraceptive types dependent on progestin type, the ratio of ethinyl estradiol-to-progestin, and route of administration. However, hormonal contraceptives do not appear to impact smooth muscle function in the macrovasculature or microvasculature, arterial stiffness, or vascular structure. Underlying mechanisms for observed impacts and areas of future research are discussed. This review provides timely consolidation of research examining hormonal contraceptives and peripheral vascular function and structure and provides guidance on considerations for hormonal contraceptive use in study design.

Sex-specific alterations in blood-borne factors in physically inactive individuals are detrimental to endothelial cell functions

Mechanisms underlying the protective effects of both habitual endurance exercise and the female sex on vascular function are incompletely understood. Blood-borne circulating factors, such as circulating microRNAs (ci-miRs), may partially explain these effects. Blood samples were obtained from young, healthy men and women who either habitually performed endurance exercise (endurance trained) or were relatively inactive (sedentary). Women were tested during the early follicular phase of the menstrual cycle or the placebo pill phase of oral contraceptive to control for estrogen. Cultured human umbilical vein endothelial cells (HUVECs) were exposed to participants' serum in migration, proliferation, and reactive oxygen species (ROS) assays. Real-time quantitative polymerase chain reaction was used to quantify an initial array of 84 cardiovascular disease (CVD)-related ci-miRs, followed by validation of 10 ci-miRs. All participants were devoid of traditional CVD risk factors, and circulating estradiol concentration was not different between groups. Serum of endurance-trained women induced greater HUVEC migration compared with serum of sedentary women. HUVEC ROS production was greater in response to serum of sedentary men compared with serum of endurance-trained men and sedentary women. There were sex effects on the levels of nine ci-miRs, with greater levels in men, while ci-miRs-140-5p and 145-5p were also higher in sedentary compared with endurance-trained men and/or women. In a sex-specific manner, habitual endurance exercise was associated with beneficial effects of serum on HUVECs. Thus, alterations in circulating factors may contribute to the protective effects of habitual endurance exercise on vascular health. Additionally, sex had a greater impact than habitual activity level on the levels of vascular-related ci-miRs.NEW & NOTEWORTHY Serum from sedentary women caused impaired endothelial migration, whereas serum from sedentary men elicited increased endothelial reactive oxygen species production as compared with serum from their endurance-trained counterparts. Select CVD-related circulating microRNAs (ci-miRs) were higher in men than women, while ci-miRs-140-5p and 145-5p were also higher in sedentary versus trained men and/or women. Our data suggest that alterations in circulating factors may contribute to the protective effects of habitual exercise and sex on vascular health.

Atherosclerosis-related biomarkers in women with endometriosis: The effects of dienogest and oral contraceptive therapy

Objective

Chronic inflammation in endometriosis is associated with increased risk of future cardiovascular disease; however, no studies have investigated the cardiovascular risk of women who have undergone hormonal therapy for endometriosis. We investigated atherosclerosis-related biomarkers in women with and without endometriosis and the effects of dienogest (DNG) and oral contraceptive (OC) therapies.

Study design

In this cross-sectional study, 109 women with endometriosis and 42 control women without endometriosis were enrolled. The endometriosis group was divided into the untreated (n = 34), DNG therapy (n = 33), and OC therapy (n = 42) groups. Lipid profile serum levels, inflammatory marker such as high-sensitivity C-reactive protein, oxidative stress markers such as oxidized low-density lipoprotein and diacron-reactive oxygen metabolites, and atherosclerosis indicators (cardio-ankle vascular index [CAVI] and ankle-brachial pressure index [ABI]) were measured.

Results

The median treatment duration was 28 months in the DNG group and 32.5 months in the OC group. Triglyceride levels were higher in the OC group than in the other three groups (P <  0.05). Regarding markers of inflammation and oxidative stress, log high-sensitivity C-reactive protein and diacron-reactive oxygen metabolites levels were higher in the untreated group than in the control group (P <  0.05), and these markers were further increased in the OC group (log high-sensitivity C-reactive protein: P <  0.05; diacron-reactive oxygen metabolites: P <  0.01), but not in the DNG group. There was no difference in the CAVI and ABI among all groups. Spearman correlation revealed a positive correlation between duration of OC therapy and CAVI (ρ = +0.49; P = 0.002), but no correlation between the duration of DNG therapy and CAVI (ρ = –0.04; P = 0.81).

Conclusions

Inflammation and oxidative stress markers are increased in women with untreated endometriosis. Treatment with OC, but not with DNG, further increases these levels. There was a positive association between the duration of OC administration and atherosclerosis risk for women with endometriosis. Our results suggest that DNG could be administered to endometriosis without the increased atherosclerosis risk and short-term OC administration for endometriosis is not harmful, however, atherosclerosis risk should be strictly observed.

Brachial artery endothelial function is stable across a menstrual and oral contraceptive pill cycle but lower in premenopausal women than in age-matched men

Sex hormone concentrations differ between men, premenopausal women with natural menstrual cycles (NAT), and premenopausal women using oral contraceptive pills (OCP), as well as across menstrual or OCP phases. This study sought to investigate how differences in sex hormones, particularly estradiol, between men and women and across cycle phases might influence brachial artery endothelial function. Fifty-three healthy adults (22 ± 3 yr, 20 men, 15 NAT women, and 18 second-, third-, or fourth-generation OCP women) underwent assessments of sex hormones and endothelial [flow-mediated dilation (FMD) test] and smooth muscle [nitroglycerin (NTG) test] function. Men were tested three times at 1-wk intervals, and women were tested three times throughout a single menstrual or OCP cycle (NAT: menstrual, midfollicular, and luteal phases and OCP: placebo/no pill, “early”, and “late” active pill phases). Endogenous estradiol concentration was comparable between men and women in their NAT menstrual or OCP placebo phase ( P = 0.36) but increased throughout a NAT cycle ( P < 0.001). Allometrically scaled FMD did not change across a NAT or OCP cycle but was lower in both groups of women than in men ( P = 0.005), whereas scaled NTG was lower only in NAT women ( P = 0.001). Changes in estradiol across a NAT cycle were not associated with changes in relative FMD ( r2 = 0.01, P = 0.62) or NTG ( r2 = 0.09, P = 0.13). Duration of OCP use was negatively associated with the average relative FMD for second-generation OCP users only ( r = −0.65, P = 0.04). Our findings suggest that brachial endothelial function is unaffected by cyclic hormonal changes in premenopausal women but may be negatively impacted by longer-term use of second-generation OCPs.

NEW & NOTEWORTHY We demonstrate that brachial artery flow-mediated dilation does not change across a menstrual or oral contraceptive pill cycle in premenopausal women but is lower in women than in men. Although unaffected by within-cycle changes in estradiol, brachial flow-mediated dilation is negatively correlated with duration of oral contraceptive pill use for second-generation pills.

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Effect of sex, menstrual cycle phase, and monophasic oral contraceptive pill use on local and central arterial stiffness in young adults

Arterial stiffness is associated with increased cardiovascular disease risk. Previous sex-based investigations of local and central stiffness report inconsistent findings and have not controlled for menstrual cycle phase in women. There is also evidence that sex hormones influence the vasculature, but their impact on arterial stiffness across a natural menstrual (NAT) or oral contraceptive pill (OCP) cycle has been understudied. This study sought to 1) examine potential sex differences in local and central stiffness, 2) compare stiffness profiles between NAT and OCP cycles, and 3) investigate the relationship between duration of OCP use and arterial stiffness. Sex hormone concentrations, β-stiffness index (local stiffness), and carotid-femoral pulse wave velocity [cfPWV (central stiffness)] were assessed in 53 healthy adults (22 ± 3 yr old, 20 men, 15 NAT women, and 18 OCP women). All participants were tested three times: men on the same day and time 1 wk apart, NAT women in menstrual, midfollicular and luteal phases of the menstrual cycle, and OCP women in placebo, early active and late active pill phases. β-Stiffness was higher in men than NAT and OCP women ( P < 0.001), whereas cfPWV was similar between groups ( P = 0.09). β-Stiffness and cfPWV did not differ across or between NAT and OCP cycles ( P > 0.05 for both) and were not associated with duration of OCP use (β-stiffness: r = 0.003, P = 0.99; cfPWV: r = -0.26, P = 0.30). The apparent sex differences in local, but not central, stiffness highlight the importance of assessing both indexes in comparisons between men and women. Furthermore, fluctuating sex hormone levels do not appear to influence β-stiffness or cfPWV. Therefore, these stiffness indexes may need to be assessed during only one cycle phase in women in future investigations. NEW & NOTEWORTHY We observed higher local, but not central, arterial stiffness in men than women. We also demonstrated that there are no differences in arterial stiffness between naturally cycling women and women who use monophasic oral contraceptive pills, and that the duration of oral contraceptive pill use does not influence arterial stiffness.

Heme-nitrosylated hemoglobin and oxidative stress in women consuming combined contraceptives. Clinical application of the EPR spectroscopy

An increased risk of venous thromboembolism was identified in young women consuming combined contraceptive pills (CP) suggesting a disturbance of vascular homeostasis but the impact of CP on endothelial function and redox status of the vasculature was not thoroughly analyzed. We measured the bioavailability of nitric oxide (NO), a main mediator of vascular homeostasis in a cohort of young female subjects (n=114) and compared the results in users or not of CPs containing ethinyl estradiol and synthetic progestogens. Vascular NO availability was measured by quantification of the heme-nitrosylated hemoglobin (5-coordinate-α-HbNO) concentrations in venous erythrocytes using Electron Paramagnetic Resonance spectroscopy (EPR). Vascular oxidative status was assessed by measurement of peroxides in plasma, and of the thiol redox state in erythrocytes. In addition, endothelial function was assessed by digital reactive hyperemia pulse tonometry using EndoPAT. We observed that the HbNO level was significantly lower in erythrocytes of subjects consuming CPs versus controls (162±8 and 217±12 nmol/L). This correlated with significantly increased levels of plasma peroxides (1.8±0.1mmol/L versus 0.8±0.1mmol/L in controls) and decreased concentrations of erythrocyte reduced thiols (by 12%). Interestingly, the level of oxidized ceruloplasmin-Cu(II) was also significantly higher in the group consuming CPs. The EndoPAT index showed a trend towards impairment in CP users, and was significantly lower in subjects that consumed CPs containing drospirenone, and had lowest erythrocyte HbNO levels.

CONCLUSION

This cross-sectional cohort study demonstrates that a decrease of HbNO measured by quantitative EPR in human venous erythrocytes is correlated with the development of endothelial dysfunction under CPs consumption, in parallel with increased vascular oxidative stress.

Cell-Based Models for Development of Antiatherosclerotic Therapies

The leading cause of death worldwide is cardiovascular disease. Among the conditions related to the term, the most prominent one is the development of atherosclerotic plaques in the walls of arteries. The situation gets even worse with the fact that the plaque development may stay asymptomatic for a prolonged period of time. When it manifests as a cardiovascular disorder, it is already too late: the unfortunate individual is prescribed with a plethora of synthetic drugs, which are of debatable efficacy in the prevention of atherosclerotic lesions and safety. Cell models could be useful for the purpose of screening substances potentially effective against atherosclerosis progression and effective in reduction of already present plaques. In this overview, we present studies making use of in vitro and ex vivo models of atherosclerosis development that can prove valuable for clinical applications.

Oral Contraceptive Use, Muscle Sympathetic Nerve Activity, and Systemic Hemodynamics in Young Women

Endogenous female sex hormones influence muscle sympathetic nerve activity (MSNA), a regulator of arterial blood pressure and important factor in hypertension development. Although ≈80% of American women report using hormonal contraceptives sometime during their life, the influence of combined oral contraceptives (OCs) on MSNA and systemic hemodynamics remains equivocal. The goal of this study was to determine whether women taking OCs have altered MSNA and hemodynamics (cardiac output and total peripheral resistance) at rest during the placebo phase of OC use compared with women with natural menstrual cycles during the early follicular phase. We retrospectively analyzed data from studies in which healthy, premenopausal women (aged 18-35 years) participated. We collected MSNA values at rest and hemodynamic measurements in women taking OCs (n=53; 25±4 years) and women with natural menstrual cycles (n=74; 25±4 years). Blood pressure was higher in women taking OCs versus those with natural menstrual cycles (mean arterial pressure, 89±1 versus 85±1 mm Hg, respectively; P=0.01), although MSNA was similar in both groups (MSNA burst incidence, 16±1 versus 18±1 bursts/100 heartbeats, respectively; P=0.19). In a subset of women in which detailed hemodynamic data were available, those taking OCs (n=33) had similar cardiac output (4.9±0.2 versus 4.7±0.2 L/min, respectively; P=0.47) and total peripheral resistance (19.2±0.8 versus 20.0±0.9 U, respectively; P=0.51) as women with natural menstrual cycles (n=22). In conclusion, women taking OCs have higher resting blood pressure and similar MSNA and hemodynamics during the placebo phase of OC use when compared with naturally menstruating women in the early follicular phase.

Early physiological markers of cardiovascular risk in community based adolescents with a depressive disorder

BACKGROUND

Depression is recognised as an independent cardiovascular risk factor in adults. Identifying this relationship early on in life is potentially important for the prevention of cardiovascular disease (CVD). This study investigated whether clinical depression is associated with multiple physiological markers of CVD risk in adolescents from the general community.

METHODS

Participants aged 12-18 years were recruited from the general community and screened for depressive symptoms. Individuals with high and low depressive symptoms were administered a diagnostic interview. Fifty participants, 25 with a current depressive episode and 25 matched healthy controls, subsequently completed cardiovascular assessments. Variables assessed were automatic brachial and continuous beat-to-beat finger arterial blood pressure, heart rate, vascular functioning by pulse amplitude tonometry following reactive hyperaemia and pulse transit time (PTT) at rest. Blood samples were collected to measure cholesterol, glucose and glycohaemoglobin levels and an index of cumulative risk of traditional cardiovascular risk factors was calculated.

RESULTS

Depressed adolescents had a significantly lower reactive hyperaemia index and shorter PTT, suggesting deterioration in vascular integrity and structure. Higher fasting glucose and triglyceride levels were also observed in the depressed group, who also had higher cumulative risk scores indicative of increased engagement in unhealthy behaviours and higher probability of advanced atherosclerotic lesions.

LIMITATIONS

The sample size and number of males who completed all cardiovascular measures was small.

CONCLUSIONS

Clinically depressed adolescents had poorer vascular functioning and increased CVD risk compared to controls, highlighting the need for early identification and intervention for the prevention of CVD in depressed youth.