Gender differences in blood flow velocities after carotid angioplasty and stenting

Gender differences have been demonstrated in blood flow velocities by duplex ultrasonography (DU) in patients with carotid stenosis. Currently, DU is the most widely used method of follow-up monitoring after carotid angioplasty and stenting (CAS). To identify possible gender differences in carotid flow velocities, we analyzed our experience with DU obtained before and immediately after CAS. In a series of 47 CAS procedures over a 2.5-year period performed in 31 men and 15 women, carotid angiograms and duplex flow velocities were obtained preoperatively and within 24 hr after CAS. Carotid velocity profiles were compared with the angiographic degree of carotid stenosis. Gender differences in blood velocities were assessed using parametric and nonparametric statistical tests. Overall, women had median blood velocities 5-10% higher than men, although the differences were not statistically significant. DU obtained immediately after CAS revealed that median blood flow velocities were very similar among men and women (P > 0.4). In conclusion, although women have higher carotid blood flow velocities than men do, gender differences are notably absent on follow-up DU after carotid stenting. Our data indicate that similar criteria should be used after CAS for interpreting carotid velocity profiles in both women and men.     

Influence of poststenotic collateral pressure on blood flow velocities within high-grade carotid artery stenosis: differences between morphologic and functional measurements

PURPOSE: The driving force for blood flow through a high-grade stenosis in the internal carotid artery can be expressed as the pressure gradient over the stenosis itself, which, however, might be reduced by the back pressure exerted by distal collateral vessels. Theoretically the maximum blood flow velocity as a measure of the functional grade of obstruction may therefore be lower than what is expected from morphologic gradations of the stenosis. This study was designed to test prospectively the influence of intracranial collateral vessels on blood flow velocities within high-grade internal carotid artery stenoses. PATIENTS AND METHODS: Forty-five consecutive patients (age 66 +/- 11) with high-grade internal carotid artery stenoses were investigated before and during carotid endarterectomy. The preoperative investigations included duplex ultrasound scanning of the neck vessels, transcranial Doppler scanning for assessment of collateral flow to the middle cerebral artery and angiography. Carotid endarterectomy was performed with patients under deep general anesthesia without a shunt. Systolic and diastolic internal carotid artery blood pressures were measured before and during intraoperative cross-clamping (ie, stump pressure) of the carotid arteries. RESULTS: Within high-grade internal carotid artery stenoses, maximum systolic and end-diastolic blood flow velocities showed a significant inverse correlation to the corresponding systolic and diastolic stump blood internal carotid artery blood pressures. All patients with spontaneous collateral flow to the ipsilateral anterior part of the circle of Willis were divided into a group with relatively high and another one with low end-diastolic blood flow velocities. The stump pressure was significantly lower in patients with high end-diastolic blood flow velocities in spite of the fact that the mean angiographic grade of stenosis did not differ significantly between the groups. CONCLUSIONS: Flow velocities within a high-grade internal carotid artery stenosis are inversely dependent on the stump pressure, that is the poststenotic collateral perfusion pressure. This should be taken into consideration in case of discrepancies between angiography and ultrasound outcome.     

Outpatient primary stent-angioplasty in symptomatic internal carotid artery stenoses

In 81 patients, average age 69.3 (57-79) years with symptomatic ICA stenosis stent implantation was performed under outpatient conditions. An interdisciplinary consensus ascertained that the patients were suitable for outpatient therapy. In accordance with the NASCET criteria all patients belonged to the high-risk group. Within 120 days before the intervention, the following clinical events had occurred: 32 minor strokes, 43 TIA, 20 amaurosis fugax. 61/81 patients revealed a bulbar, 20/81 a postbulbar ICA stenosis, the average degree of stenosis was 88.6 % (75-97). Stent application, using 3 different stent models, and subsequent PTA were always performed under protection. The transfemoral route was always treated with an endovascular closure system. All patients were given follow-up examinations by means of colour duplex sonography (CDS) of the neck vessels on days 1, 30, 180 and 360, and contrast-medium intensified MRT on day 5 post-intervention. The technical success rate with regard to stenting and PTA was 100 %. One case of hypotonic dysregulation occurred during the intervention. Atheromatous particles and plaque fragments were found in the protection system in 3/81 (3.7%) of the patients. A plaque embolism was excluded clinically and in the contrast-medium intensified MRT 5 days after the intervention in 79/81 (97.5%) of the patients, while two patients were found to sustain an asymptomatic cortical barrier impairment. After 180 days, no restenosis or stent dislocation were found in the CDS, all ECAs were perfused. After 360 days, one asymptomatic occlusion and four restenoses > 70% were found (5/81 = 6.2% restenosis rate after 1 year), which were successfully treated by angioplasty. The method presented bears a low complication rate and shows a high success rate. If patient recruitment is adequate, this intervention can safely be performed on an outpatient basis.     

Gender differences in pain

A literature survey reveals clear evidence of sex differences in the incidence of painful conditions and their severity, both being greater in women. The possible causes of this sexual dimorphism are discussed. Sex-role stereotyping may be relevant and there is evidence to indicate that, perhaps through their roles as carers, women seek and utilize more medical services than men. Less clear-cut evidence for anatomical and physiological differences is reviewed, together with documentation of hormonal (and reproductive cycle) influences on the operation of those systems.     

Gender differences in benign renal masses

Purpose

To examine gender-specific differences in benign renal tumors.

Methods

This retrospective study included 135 adult Caucasian patients with 143 benign renal tumors, which were treated surgically at a single institution. Demographics, comorbidity, histology, renal function, and management were compared by gender. A systematic review and meta-analysis of the literature were performed.

Results

A total of 73 women were compared with 62 men. The female-to-male ratio was significantly higher in patients with benign renal tumors than in those with renal cell carcinoma (1.18:1 vs. 0.57:1, p < 0.001). Only 17 % of benign renal tumors were correctly classified by preoperative computed tomography. The most frequently observed histological types were oncocytoma (44 %) and angiomyolipoma (37 %). Angiomyolipoma occurred more than twice as often in women than in men (72 vs. 28 %), while oncocytoma was more frequently found in men (59 vs. 41 %, p = 0.001). Men with benign renal tumors were older (p = 0.002) and had higher body mass indices (p = 0.019), higher comorbidity indices (p < 0.001), lower ECOG performance status (p < 0.001), and smaller tumors (p = 0.045). No differences were seen in pack years, mode of diagnosis, bilaterality, renal function, use of laparoscopic surgery, and the rate of radical nephrectomy. In the meta-analysis of 9,665 renal tumors, women had a 2.55-fold increased chance of benign pathology and a greater chance of angiomyolipoma (OR 4.66) than men.

Conclusions

This study demonstrated several gender-specific differences in benign renal tumors, especially in the histological types. Despite this, clinical–pathological features and management of benign renal tumors in men and women appear more alike than different.     

Gender differences in patellofemoral joint biomechanics

Patellofemoral pain is associated with patellar malalignment and quadriceps weakness which are seen more commonly in women. The objective of the current study was to determine the effects of gender, vastus medialis strength, and tibial rotation on patellofemoral joint biomechanics. Twelve fresh-frozen knees from cadavers were tested using a custom knee jig. Anatomic multiplane loading of the extensor mechanism was used with varying vastus medialis loads. Patellofemoral contact area and pressure were measured using pressure sensitive film at knee flexion angles of 0 degrees, 30 degrees, 60 degrees, and 90 degrees with the tibia in neutral and 15 degrees internal and external tibial rotation. Patellofemoral joint contact areas in specimens from men were larger at knee flexion angles greater than 30 degrees. A significant increase in mean patellofemoral contact pressures was seen for specimens from women when compared with specimens from men at 0 degrees and 30 degrees knee flexion. The knees from women also showed a greater change in contact pressures to varying vastus medialis load at knee flexion angles of 0 degrees, 30 degrees, and 60 degrees. The results of the current study indicate that there are gender differences in patellofemoral contact areas and pressures. These differences may help explain the increased incidence of patellofemoral disorders in women.     

Gender differences in chronic kidney disease

Women live longer than men. Can this phenomenon be explained by chronic kidney disease (CKD)? Gender differences in the prevalence and incidence of CKD are discussed.     

Gender differences in anesthesiologists' annual incomes

BACKGROUND: Specialty, work effort, and gender have been shown to be associated with physicians' annual incomes; however, careful examination of the association between provider gender and annual income after correcting for other factors likely to influence income has not been conducted for anesthesiologists. METHODS: Survey responses collected throughout the 1990s from 819 actively practicing anesthesiologists and linear regression analysis were used to determine the association between provider gender and annual incomes after controlling for work effort, provider characteristics, and practice characteristics. RESULTS: White female anesthesiologists reported working 12% fewer annual hours than their white male counterparts. White female anesthesiologists had practiced medicine for fewer years than white males and were more likely to be employees, as opposed to having an ownership interest in the practice, but less likely to be board certified. After adjustment for work effort, provider characteristics, and practice characteristics, white females' mean annual income was 236,628 dollars, or 60,337 dollars (20%) lower than that for white males (95% confidence interval, 81,674 dollars lower to 39,001 dollars lower; P < 0.001). CONCLUSIONS: During the 1990s, female gender was associated with lower annual incomes among anesthesiologists. These findings warrant further exploration to determine what factors might cause these gender-based income differences.