Sex-associated differences in the modulation of vascular risk in patients with asymptomatic carotid stenosis

Stroke territory and atherosclerosis in ischemic stroke patients with a history of migraine with aura

Introduction

The mechanisms subtending the increased stroke risk in migraine with aura (MA) are not fully understood. Our study aims to evaluate if the clinical profile in stroke patients with MA differentiates from those without MA.

Methods

We retrieved the prospective registered electronic clinical dossiers of adult patients younger than 60 years with acute ischemic stroke admitted in four hospitals between January 2016 and June 2022. Patients were classified by the history of MA (MA+ and MA-).

Results

We identified 851 stroke patients (59 MA+, 6.9%). Compared to MA-, MA+ patients were characterized by younger age (44.0 ± 10.6 vs 50.1 ± 8.2 years), female sex (59.3% vs 29.0%), and affected by cryptogenic (OR 2.594 95% CI 1.483-4.537), and cerebellar stroke (OR 3.218 95% CI 1.657-6.250; p ≤ 0.001 for all comparisons). After adjusting for age and sex, MA+ patients presented less frequently hypertension (OR 0.349 95% CI 0.167-0.470; p=0.005) and dyslipidemia (OR 0.523 95% CI 0.280-0.974; p = 0.041). After adjusting also for risk factors, the MA+ group had less frequently symptomatic large vessel stenosis (OR 0.126 95% CI 0.017-0,924; p = 0.042) and clinical atherosclerosis (OR 0.103 95% CI 0.014-0.761; p = 0.026), while intima-media thickness did not differ (p = 0.395).

Discussion

Cryptogenic and cerebellar stroke and fewer vascular risk factors and clinical atherosclerosis seem to characterize stroke patients with MA.

Sex-specific risk factors of carotid atherosclerosis progression in a high-risk population of cardiovascular disease

BACKGROUND

The progression of carotid intima-media thickness (cIMT) and plaques are associated with cardiovascular health, especially for high-risk population of cardiovascular disease (CVD).

HYPOTHESIS

Risk factors for atherosclerosis may vary by sex. This study aimed to investigate the sex-specific risk factors of cIMT and plaque progression.

METHODS

We selected subjects who were identified as high-risk population of CVD, and collected their carotid ultrasound data and baseline characteristics. Linear regression and logistic regression analyses were used to identify risk factors for cIMT and plaque progression. Sex-specific risk factors were identified respectively.

RESULTS

A total of 7908 participants were included. The mean age was 57.75 ± 9.45 years and 61.51% were female. During mean follow-up of 1.92 ± 0.89 years, the median annual cIMT change rate was -7.25 μm/year. Seven hundred and fifteen subjects free from plaques at baseline developed plaque. Age, smoking, hypertension, and diabetes were common risk factors for carotid atherosclerosis progression in all participants. Smoking and alcohol drinking were significantly associated with increased cIMT change in women, while hypertension and antihypertensive medication were significant in men. Increased total cholesterol and diabetes were significantly associated with new plaque presence in women, while smoking, increased triglyceride, and dyslipidemia were significant in men (p ˂ .05 for all cases). The association of baseline cIMT and smoking with annual cIMT change rate and increased total cholesterol with new plaque presence were significantly differentiated between both sexes (p for interaction ˂ .05).

CONCLUSIONS

The risk factors for cIMT and plaque progression differed by sex.

Female Gender Increases Risk of Stroke and Readmission after CEA and CAS

OBJECTIVES

Carotid endarterectomy (CEA) has historically demonstrated a higher rate of perioperative adverse events for female patients. However, recent evidence suggests similar outcomes for CEA between genders. In contrast, fewer studies have examined gender in carotid artery stenting (CAS). Using contemporary data from the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database, we aim to determine if gender impacts differences in postoperative complications in patients who undergo CEA or CAS.

METHODS

The ACS NSQIP database was queried from 2005-2017 using Current Procedural Terminology (CPT) and International Classification of Diseases (ICD) codes for retrospective review. Patients with carotid intervention (CEA or CAS) were stratified into asymptomatic vs symptomatic cohorts to determine the effect of gender on 30-day postoperative outcomes. Symptomatic patients were defined as those with perioperative transient cerebral ischemic attack or stenosis of carotid artery with cerebral infarction. Descriptive statistics were calculated. Risk-adjusted odds of 30-day postoperative outcomes were calculated using multivariate regression analysis with fixed effects for age, race, and comorbidities.

RESULTS

There were 106,568 patients with CEA or CAS (104,412 CEA and 2,156 CAS). Average age was 70.9 years old and female patients accounted for 39.9% of the population. For asymptomatic patients that underwent CEA or CAS, female gender was associated with significantly higher rates of CVA/stroke (13%, p=0.005), readmission (10%, p=0.004), bleeding complication (32%, p=0.001), and UTI (54%, p=0.001) as well as less infection (26%, p=0.001). In the symptomatic cohort, female gender was associated with significantly higher rates of CVA/stroke (32%, p=0.034), bleeding complication (203%, p=0.001), and UTI (70%, p=0.011), while female gender was associated with a lower rate of pneumonia (39%, p=0.039). Subset analysis found that, compared to male patients, female patients <75yo have an increased rate of CVA/stroke (21%, p=0.001) and readmission (15%, p<0.001), while female patients ≥75yo did not. In asymptomatic and symptomatic patients that underwent CEA, female gender was associated with significantly higher rates of CVA/stroke (13%, p=0.006 and 31%, p=0.044, respectively), but this finding was present not in patients undergoing CAS.

CONCLUSION

In patients undergoing carotid intervention, female gender was associated with significantly increased rates of postoperative CVA/stroke in the asymptomatic and symptomatic cohorts as well as readmission in the asymptomatic cohort. Female gender was associated with higher rates of CVA/stroke following CEA, but not CAS. We recommend that randomized control trials ensure adequate representation of female patients to better understand gender-based disparities in carotid intervention.

Left Common Carotid Artery Biomechanical Properties in Individuals over 80 years: Women Have Stiffer Vessels

BACKGROUND

Considering the longevity of the worldwide population, the cardiovascular diseases deserve particular attention, especially the carotid artery disease in the ≥80-year-old population. The stiffness of the common carotid artery, for example, has been showed in numerous clinical studies as a marker of increased risk of stroke, dementia, and depression. Besides, with the emergence of new surgical techniques such as the transcarotid artery revascularization that uses the common carotid artery as a workstation, the biomechanical and histological features of this vessel, more than ever, must be detailed.

METHODS

Left common carotid artery fragments from 9 cadaver donors (≥80 years old) were evaluated. Biomechanical (failure stress, tension, and strain) and histological (percentage of collagen and elastic fibers) features of these samples were analyzed with special focus on gender differences.

RESULTS

Statistically significant differences in biomechanical and histological features between the genders were observed. The percentage of collagen fiber in intima (P = 0.008) and media (P = 0.041) layers was significantly lower in men than in women. A higher elasticity (failure strain) of the specimens in male gender was also observed (P = 0.025). No significant difference was observed in the layers thickness between the genders regardless which part of the arterial wall was considered.

CONCLUSIONS

These biomechanical and histological findings could be the responsible for the higher left common carotid artery stiffness observed among ≥80-year-old women when compared with men in numerous clinical studies in literature.

Fatal Ovarian Hemorrhage Associated With Anticoagulation Therapy in a Yucatan Mini-Pig Following Venous Stent Implantation

Swine models are commonly utilized in endovascular research for development of intravascular interventions and medical device development. As part of a pilot study for a venous vascular stent device, a 5-year-old female Yucatan mini-pig underwent bilateral external iliac vein stent placement under general anesthesia. To reduce thrombotic complications by reduction of thrombus formation on wires, sheaths, and catheters, the pig was heparinized with a total of 300 IU/kg of heparin, establishing an activated clotting time (ACT) of 436 s. The ACT had returned to below 200 s by the end of the procedure. To prevent postoperative thrombosis, the pig received an anticoagulation therapy protocol consisting of enoxaparin, clopidogrel, and aspirin. There were no complications during the immediate postoperative period. However, the pig died 4 days after surgery. Necropsy established the cause of death as abdominal exsanguination due to severe, acute, intra-ovarian hemorrhage, most likely related to ovulation. Life-threatening ovarian hemorrhage is occasionally seen in women with congenital or acquired bleeding disorders; to our knowledge this is the first report of fatal ovarian hemorrhage in an animal enrolled in a pre-clinical research trial.

miRNA as a New Regulatory Mechanism of Estrogen Vascular Action

The beneficial effects of estrogen on the cardiovascular system have been reported extensively. In fact, the incidence of cardiovascular diseases in women is lower than in age-matched men during their fertile stage of life, a benefit that disappears after menopause. These sex-related differences point to sexual hormones, mainly estrogen, as possible cardiovascular protective factors. The regulation of vascular function by estrogen is mainly related to the maintenance of normal endothelial function and is mediated by both direct and indirect gene transcription through the activity of specific estrogen receptors. Some of these mechanisms are known, but many remain to be elucidated. In recent years, microRNAs have been established as non-coding RNAs that regulate the expression of a high percentage of protein-coding genes in mammals and are related to the correct function of human physiology. Moreover, within the cardiovascular system, miRNAs have been related to physiological and pathological conditions. In this review, we address what is known about the role of estrogen-regulated miRNAs and their emerging involvement in vascular biology.

Determinants of carotid atherosclerotic plaque burden in a stroke-free population

BACKGROUND AND AIMS

In a large stroke-free population, we sought to identify cardiovascular risk factors and carotid plaque components associated with carotid plaque burden, lumen volume and stenosis.

METHODS

The carotid arteries of 1562 stroke-free participants from The Rotterdam Study were imaged on a 1.5-Tesla MRI scanner. Inner and outer wall of the carotid arteries were automatically segmented and lumen volume (mm³), wall volume (outer wall-inner wall) and plaque burden (wall volume/outer wall volume) (%) were quantified. Plaque components were visually determined and luminal stenosis was assessed. We analyzed associations of cardiovascular risk factors and carotid plaque components with plaque burden and lumen volumes using regression analysis.

RESULTS

We investigated 2821 carotid plaques and found that women had larger plaque burden (50.7 ± 7.8% vs. 49.2 ± 7.7%, p < 0.0001) and smaller lumen volumes (933 ± 286 mm³vs. 1078 ± 334 mm³, p < 0.0001) than men. In women, age, HDL-cholesterol and systolic blood pressure, and in men, total cholesterol, non-HDL cholesterol and statin use were independently associated with higher plaque burden and lumen volume. Furthermore, smoking and diabetes were associated with lumen volume in men (respectively p = 0.04 and p = 0.002). Intraplaque hemorrhage (IPH) and lipid were related to a larger plaque burden (OR 1.30 [1.05-1.60] and OR 1.28[1.06-1.55]). Finally, within the highest quartile of plaque burden, IPH was strongly associated with luminal stenosis independent of age, sex, plaque burden and composition (Beta = 15.2; [11.8-18.6]).

CONCLUSIONS

Several cardiovascular risk factors and plaque components, in particular IPH, are associated with higher plaque burden. Carotid IPH is strongly associated with an increased luminal stenosis.

Is Carotid Stenosis in Women a Gender-Related Condition?

BACKGROUND

We set out to study, through ultrasound examinations, the carotid bifurcation in men and women with/without carotid stenosis to look for anatomical and electrophysiologic differences. We evaluated other variables to look for differences that might explain the dissimilar behavior of this disease in the two sexes and the presence and impact of risk factors.

METHODS

We examined 974 subjects aged 25 to 88 years (478 men and 496 women) in whom we considered heart rate, smoking status, and the presence of hypertension, diabetes, hypercholesterolemia, and hypertriglyceridemia. Ultrasound examination of the neck vessels included measurement of intimal medial thickness (IMT), vessel diameter, and outflow area/inflow area ratio. We established plaque location, echogenicity and echostructure, and the percentage of stenosis owing to plaque and measured systolic velocity, flow direction, and the depth of detection of these parameters. We used the apnea and hyperpnea test to assess cerebrovascular reactivity.

RESULTS

Hypertension and hypercholesterolemia were the most frequent risk factors. Women had a higher heart rate, whereas men had significantly greater IMT. The presence of atheromatous plaque was significantly correlated with age in both sexes, with men having a higher prevalence of carotid plaques. The sexes differed significantly with regard to plaque location, echogenicity, echostructure, and intracranial circulation. Women had a slightly higher blood flow velocity in the intracranial arteries. Risk factors affected plaque formation and extent more in men than in women.

CONCLUSIONS

These findings suggest that carotid stenosis is a gender-related trait.

Sirtuin/uncoupling protein gene variants and carotid plaque area and morphology

BACKGROUND

Sirtuins and uncoupling proteins have been implicated in cardiovascular diseases by controlling oxidative stress.

AIMS

We sought to investigate the association of sirtuins and uncoupling proteins single nucleotide polymorphisms with total carotid plaque area and morphology measured by ultrasonographic gray scale median.

METHODS

We analyzed 1356 stroke-free subjects (60% women, mean age = 68 ± 9 years) from the Northern Manhattan Study. Multiple linear regression models were used to evaluate the association of 85 single nucleotide polymorphisms in 11 sirtuins/uncoupling protein genes with total plaque area and gray scale median after controlling for demographics, vascular risk factors (RFs), and population stratification. We investigated effect modifications of these relationship by gender and RFs and performed stratified analysis if the interaction effect had P < 0·005.

RESULTS

Among individuals with present plaque (55%), the mean total plaque area was 20·3 ± 20·8 mm(2) and gray scale median 90 ± 29. After adjustment, SIRT6 rs107251 was significantly associated with total plaque area (β = 0·30 per copy of T allele increase, Bonferroni-corrected P = 0·005). T allele carriers of rs1430583 in UCP1 showed a decreased gray scale median in women but not in men. The minor allele carriers of rs4980329 and rs12363280 in SIRT3 had higher gray scale median in men but not in women. Variants in UCP3 gene were significantly associated with higher mean gray scale median in individuals with dyslipidemia.

CONCLUSION

Our findings suggest that polymorphisms in SIRT6/UCP1 genes may be important for increased carotid plaque burden and echodensity, but translation of these findings to an individual risk of cerebrovascular events needs further investigation. Significant associations of rs1430583 in women, rs12363280 in men, and rs1685354 in those with dyslipidemia also deserve further investigations.