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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

5 cases of vascular complications--hemorrhagic stroke, myocardial infarction, retinal vein thrombosis, thrombotic stroke and deep vein thrombosis--in young women taking low dose oral contraceptives are described from the Department of Obstetrics and Gynecology, University of the Witwatersrand, Johannesburg, South Africa. The hemorrhagic stroke occurred in 1987 in a 24-year old heavy smoker taking Triphasil (Wyeth) for 12 months. She recovered fully. A 34-year old woman had an anteroseptal infarction while on Minovlar ED (Schering, 50 mcg ethinyl estradiol and 1 mg norethisterone acetate) for 2 years. She had no risk factors other than smoking 5 cigarettes daily. The woman with retinal vein thrombosis had 2 episodes, the 1st while taking Restovar 28 (Organon, 37.5 mcg ethinyl estradiol and 0.75 mg lynestrenol) for 7 years. 19 months later she began Diane (Schering AG, 50 mcg ethinyl estradiol and 2 mg cyproterone acetate) and had a bilateral retinal vein thrombosis leaving her partially blind. The woman with thrombotic stroke was 24 when she was struck in 1986, after 1 year of taking Logynon ED (Schering AG, 6/5/7 days, 30,40/40 mcg ethinyl estradiol and o.5/0.75/0.125 mg levonorgestrel). The patient with deep vein thrombosis was 19, smoked, and had used Triphasil for 2.5 years.
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PMID:Vascular complications in women using the low steroid content combined oral contraceptive pills: case reports and review of the literature. 220 50

A number of clinical trials suggest that the antithrombotic effect of aspirin is limited to men. To test the possibility that this is due to a sex difference in the inhibitory effect of aspirin on platelet behavior, we studied whole-blood platelet aggregation in men and women and in male patients with carcinoma of the prostate receiving hormone therapy. The in vitro inhibitory effect of aspirin on so-called spontaneous platelet aggregation induced by stirring whole blood and monitored by the decrease in the number of singleton platelets was greater in men (mean +/- SD inhibitory ratio 1.54 +/- 0.30 in men, 1.23 +/- 0.22 in women; p less than 0.001). The inhibitory effect of aspirin was reduced in orchiectomized male patients and was restored by the addition of testosterone to blood samples. Estradiol had no detectable influence on the inhibitory effect of aspirin. Testosterone thus seems to influence platelet aggregation and its inhibition by aspirin as assessed by whole-blood in vitro aggregometry. Possible mechanisms for this effect of testosterone and its relevance to the choice of antithrombotic therapy are discussed.
Stroke 1989 Jan
PMID:Sex difference in antithrombotic effect of aspirin. 291 32

Three studies directly evaluated the effects of oral contraceptive (OC) use on migraine headache frequency. The Walnut Creek Study in 1980 was unable to demonstrate a higher frequency of migraine headache in OC users discharged from the hospital as compared with nonusers. Another study in 1978 evaluated the effect of 0.5 mg of norgestrel and 50 mcg of ethinyl estradiol (Ovral) on 40 migraine sufferers. 20 patients received this preparation for the first 2 months of the study, the other 20 did not. 29 patients experienced worsening of their headaches with OC use. However, one-third of the patients did note improvement in their headaches. A third study in 1976 of women suffering from migraine suggested that about one-third of women noted worsening of their headaches while taking OCs. The risks of cerebrovascular accident (CVA) include advancing age, smoking, and the use of high-dose pills. Increase in blood pressure, platelet aggregatability, and cholesterol deposition are the three known mechanisms of the risk of stroke. No blind study of the subject has even been made, and a significant minority of OC users reported improvements in their migraine headaches. Circumstantial evidence suggests that there is an increased risk of stroke in OC users, although these case control studies differed with regard to the degree of relative risk. Two of three cohort studies were unable to demonstrate the increased risk of CVA among these women. The absolute risk of thrombotic stroke remains small for OC users, and the absolute risk is probably very small even for those taking OCs. However, the risk of hemorrhagic stroke may increase fivefold in those smoking. For nonsmokers, OC use is probably safer in all age groups than no contraception. A 1977 study showed that 40-44 year old nonsmokers taking OCs had an estimated death rate of 7/100,000. In contrast, those who used no method of contraception had a higher mortality rate of 23/100,000.
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PMID:Relationship of migraine headache and stroke to oral contraceptive use. 354 Feb 97

Mice were implanted subcutaneously with a pellet containing 0.5 mg estradiol or with a placebo. Eight to 12 days later platelet aggregation was produced in pial arterioles by injuring their endothelium in vivo with a noxious light/dye stimulus. The time between the onset of the noxious stimulus and the appearance of platelet aggregates was significantly shortened (p less than .02) by estradiol treatment in young (2 month old) mice. The same treatment had the opposite effect in 4-6 month old mice and significantly delayed the onset of aggregation (p = .01). When platelet rich plasma (PRP) was prepared, aggregation by sodium arachidonate was always inhibited in PRP from estradiol treated mice, irrespective of age. Estradiol treatment had no effect on aggregation induced ex vivo by ADP. Thus the enhanced aggregation observed in pial arterioles of young estradiol treated mice may not reflect direct effects of estradiol on the platelet itself. The data are discussed in light of the literature suggesting enhancement of ischemic vascular disease, including strokes, in patients receiving estrogens, and especially high doses of estrogens.
Stroke
PMID:Effects of estradiol on platelet aggregation in cerebral microvessels of mice. 393 2

We studied 374 women taking oral contraceptives, 284 women taking estrogen preparations after menopause, and 1086 women taking no hormones, to determine the relation of plasma lipids and lipoprotein cholesterol concentrations to various types of estrogen/progestin formulations. Premenopausal women, using oral contraceptives containing a relatively low dose of estrogen combined with a medium or high dose of progestin (Norlestrin, Ovral, or Demulen) had a 24 per cent higher median concentration of low-density-lipoprotein cholesterol than did those not using hormones (P less than 0.05). Women using oral contraceptives that are high in estrogen and low in progestin (Enovid or Oracon) had significantly higher concentrations of high-density-lipoprotein cholesterol than did nonusers; those using Ovral, a low-estrogen and high-progestin formulation, had significantly lower levels of high-density-lipoprotein cholesterol. In postmenopausal women the use of estrogen was associated with concentrations of low-density-lipoprotein cholesterol that were 11 to 19 per cent below the levels in postmenopausal women who did not use hormones. The effects of estrogen-progestin balance on low-density and high-density lipoproteins may underlie the increased incidence of stroke and myocardial infarction in women of childbearing age who take oral contraceptives.
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PMID:Effect of estrogen/progestin potency on lipid/lipoprotein cholesterol. 657 85

A leading patient complaint is headaches which tend to occur more often in women than men. Nonvascular headache is the most common and is caused by tension or muscle contraction. Oral contraceptives (OCs) do not affect nonvascular headaches. They can also be safely used in women who experience common migraines whose symptoms do not become more severe or frequent during OC use. On the other hand, women who have classic migraine (headache accompanied by focal neurologic symptoms) or common migraine with symptoms becoming more severe or frequent during OC use should discontinue OC use. Instead, they should use a barrier method or the IUD. Estradiol treatment appears to be effective in treating menstrual migraine. Since the data are inconclusive about the effect of OCs on young women who have experienced a stroke or transient ischemic attacks, it would be best for them to use a barrier method. Most antiepileptic drugs (phenobarbital, phenytoin, paramethadione, and carbamazepine) cause enzyme induction which may be linked to decreased levels of estrogen and increases in irregular bleeding, thereby increasing the likelihood of an epileptic OC user becoming pregnant. Possible contraceptive failure exposes a developing fetus to the teratogenic properties of the antiepileptic drugs. Thus, physicians should prescribe OCs with 50 mcg of ethinyl estradiol rather than 35 mcg ethinyl estradiol. Epileptic women can also use Depo-Provera, because it is not only effective in preventing pregnancy but reduces seizure frequency. It is important for any contraceptive method chosen for epileptic women to be effective because pregnancy intensifies seizures which in turn can damage the mother and/or fetus and cause neonatal distress.
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PMID:Contraceptive methods for women with neurologic disorders. 851 48

Clinical studies demonstrate that estrogen replacement therapy in postmenopausal women may enhance cognitive function and reduce neurodegeneration associated with Alzheimer's disease and stroke. This study assesses whether physiologic levels of estradiol prevent brain injury in an in vivo model of permanent focal ischemia. Sprague-Dawley rats were ovariectomized; they then were implanted, immediately or at the onset of ischemia, with capsules that produced physiologically low or physiologically high 17beta-estradiol levels in serum (10 or 60 pg/mL, respectively). One week after ovariectomy, ischemia was induced. Estradiol pretreatment significantly reduced overall infarct volume compared with oil-pretreated controls (mean+/-SD: oil = 241+/-88; low = 139+/-91; high = 132+/-88 mm3); this protective effect was regionally specific to the cortex, since no protection was observed in the striatum. Baseline and ischemic regional CBF did not differ between oil and estradiol pretreated rats, as measured by laser Doppler flowmetry. Acute estradiol treatment did not protect against ischemic injury. Our finding that estradiol pretreatment reduces injury demonstrates that physiologic levels of estradiol can protect against neurodegeneration.
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PMID:Estradiol protects against ischemic injury. 980 15

Estradiol protects against brain injury, neurodegeneration, and cognitive decline. Our previous work demonstrates that physiological levels of estradiol protect against stroke injury and that this protection may be mediated through receptor-dependent alterations of gene expression. In this report, we tested the hypothesis that estrogen receptors play a pivotal role in mediating neuroprotective actions of estradiol and dissected the potential biological roles of each estrogen receptor (ER) subtype, ER alpha and ER beta, in the injured brain. To investigate and delineate these mechanisms, we used ER alpha-knockout (ER alpha KO) and ER beta-knockout (ER beta KO) mice in an animal model of stroke. We performed our studies by using a controlled endocrine paradigm, because endogenous levels of estradiol differ dramatically among ER alpha KO, ER beta KO, and wild-type mice. We ovariectomized ER alpha KO, ER beta KO, and the respective wild-type mice and implanted them with capsules filled with oil (vehicle) or a dose of 17 beta-estradiol that produces physiological hormone levels in serum. One week later, mice underwent ischemia. Our results demonstrate that deletion of ER alpha completely abolishes the protective actions of estradiol in all regions of the brain; whereas the ability of estradiol to protect against brain injury is totally preserved in the absence of ER beta. Thus, our results clearly establish that the ER alpha subtype is a critical mechanistic link in mediating the protective effects of physiological levels of estradiol in brain injury. Our discovery that ER alpha mediates protection of the brain carries far-reaching implications for the selective targeting of ERs in the treatment and prevention of neural dysfunction associated with normal aging or brain injury.
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PMID:Estrogen receptor alpha, not beta, is a critical link in estradiol-mediated protection against brain injury. 1117 57

Estradiol reduces brain injury from many diseases, including stroke and trauma. To investigate the molecular mechanisms of this protection, the effects of 17-beta-estradiol on heat shock protein (HSP) expression were studied in normal male and female rats and in male gerbils after global ischemia. 17-beta-estradiol was given intraperitoneally (46 or 460 ng/kg, or 4.6 microg/kg) and Western blots performed for HSPs. 17-beta-estradiol increased hemeoxygenase-1, HSP25/27, and HSP70 in the brain of male and female rats. Six hours after the administration of 17-beta-estradiol, hemeoxygenase-1 increased 3.9-fold (460 ng/kg) and 5.4-fold (4.6 microg/kg), HSP25/27 increased 2.1-fold (4.6 microg/kg), and Hsp70 increased 2.3-fold (460 ng/kg). Immunocytochemistry showed that hemeoxygenase-1, HSP25/27,and HSP70 induction was localized to cerebral arteries in male rats, possibly in vascular smooth muscle cells. 17-beta-estradiol was injected intraperitoneally 20 minutes before transient occlusion of both carotids in adult gerbils. Six hours after global cerebral ischemia, 17-beta-estradiol (460 ng/kg) increased levels of hemeoxygenase-1 protein 2.4-fold compared with ischemia alone, and HSP25/27 levels increased 1.8-fold compared with ischemia alone. Hemeoxygenase-1 was induced in striatal oligodendrocytes and hippocampal neurons, and HSP25/27 levels increased in striatal astrocytes and hippocampal neurons. Finally, Western blot analysis confirmed that estrogen induced heat shock factor-1, providing a possible mechanism by which estrogen induces HSPs in brain and other tissues. The induction of HSPs may be an important mechanism for estrogen protection against cerebral ischemia and other types of injury.
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PMID:17-beta-estradiol induces heat shock proteins in brain arteries and potentiates ischemic heat shock protein induction in glia and neurons. 1182 16

Outlined is a protocol for the administration of emergency contraceptive pills. The indication for such treatment is unprotected intercourse within the past 72 hours. Absolute contraindications include the possibility of an existing pregnancy and a family history of stroke, heart attack, thrombophlebitis, breast or endometrial cancer, or liver tumor. Possibly excluded, depending on evaluation by a physician, are women with abnormal vaginal bleeding, active hepatitis, active gallbladder disease, high blood pressure, acute focal migraine, breastfeeding women, and those unable to understand instructions. The recommended regimen consists of six tablets of Ovral (two taken immediately, two more in 12 hours) or 12 tablets of Lo/Ovral, Nordette, or Levlen (four taken immediately, repeat dosage in 12 hours). The extra pills are to be used in cases of vomiting within three hours of pill ingestion. Women with a history of oral contraceptive-related nausea and vomiting should be provided with Compazine. Women should be informed that this method is effective in only about 92% of cases. All women who receive emergency contraception should be counseled that this is strictly a back-up method and helped to formulate a long-term birth control strategy.
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PMID:Emergency contraceptive pills (ECP) protocol. 1228 80


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