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R McBride

Publications and source records attributed to R McBride.

At least 19 recordsLinked to original sources
PubMed2001

Significant pelvic recurrence in high-risk pathologic stage I--IV endometrial carcinoma patients after adjuvant chemotherapy alone: implications for adjuvant radiation therapy.

OBJECTIVE: To evaluate the risk of pelvic recurrence (PVR) in high-risk pathologic Stage I--IV endometrial carcinoma patients after adjuvant chemotherapy alone. METHODS: Between 1992 and 1998, 43 high-risk endometrial cancer patients received adjuvant chemotherapy. All patients underwent primary surgery consisting of total abdominal hysterectomy and bilateral salpingo-oophorectomy. No patients received preoperative radiation therapy (RT). Regional lymph nodes and peritoneal cytology were sampled in 62.8% and 83.7% of cases, respectively. Most patients had Stage III--IV disease (83.7%) or unfavorable histology tumors (74.4%). None had evidence of extra-abdominal disease. All patients received 4-6 cycles of chemotherapy as the sole adjuvant therapy, consisting primarily of cisplatin and doxorubicin. Recurrent disease sites were divided into pelvic (vaginal, nonvaginal) and extrapelvic (para-aortic, upper abdomen, liver, and extra-abdominal). Median follow-up was 27 months (range, 2--96 months). RESULTS: Twenty-nine women (67.4%) relapsed. Seventeen (39.5%) recurred in the pelvis and 23 (55.5%) in extrapelvic sites. The 3-year actuarial PVR rate was 46.5%. The most significant factors correlated with PVR were cervical involvement (CI) (p = 0.01) and adnexal (p = 0.05) involvement. Of the 17 women who developed a PVR, 8 relapsed in the vagina, 3 in the nonvaginal pelvis, and 6 in both. The 3-year vaginal and nonvaginal PVR rates were 37.8% and 26%, respectively. The most significant factor correlated with vaginal PVR was CI (p = 0.0007). Deep myometrial invasion (p = 0.02) and lymph nodal involvement (p = 0.03) were both correlated with nonvaginal PVR. Nine of the 29 relapsed patients (31%) developed PVR as their only (6) or first site (3) of recurrence. Factors associated with a higher rate of PVR (as the first or only site) were CI and Stage I--II disease. CONCLUSIONS: PVR is common in high-risk pathologic Stage I-IV endometrial cancer patients after adjuvant chemotherapy alone. These results support the continued use of locoregional RT in patients undergoing adjuvant chemotherapy. Further studies are needed to test the addition of chemotherapy to locoregional RT.

Adenocarcinoma↗
PubMed2001

Right versus left prefrontal transcranial magnetic stimulation for obsessive-compulsive disorder: a preliminary investigation.

BACKGROUND: There is preliminary evidence that repetitive transcranial magnetic stimulation (rTMS) may be useful for the treatment of obsessive-compulsive disorder (OCD), but no definitive study has been published, and the effect of laterality of stimulation is uncertain. METHOD: Subjects (N = 12) with resistant OCD were allocated randomly to either right or left prefrontal rTMS daily for 2 weeks and were assessed by an independent rater at 1 and 2 weeks and 1 month later. RESULTS: Subjects had an overall significant improvement in the obsessions (p < .01), compulsions (p < .01), and total (p < .01) scores on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) after 2 weeks and at 1-month follow-up. This improvement was significant for obsessions (p < .05) and tended to significance for total Y-BOCS scores (p = .06) after correction for changes in depression scores on the Montgomery-Asberg Depression Rating Scale. There was no significant difference between right- and left-sided rTMS on any of the parameters examined. Two subjects (33%) in each group showed a clinically significant improvement that persisted at I month but with relapse later in I subject. CONCLUSION: A proportion (about one quarter) of patients with resistant OCD appear to respond to rTMS to either prefrontal lobe, although in the absence of a sham treatment group in this study, we cannot rule out the possibility of this being a placebo response. This treatment warrants further investigation to better establish its efficacy and examine the best parameters for response.

Adult↗
PubMed2000

Separating favorable from unfavorable prognostic markers in breast cancer: the role of E-cadherin.

Distant metastases are the major cause of morbidity and mortality in women with breast cancer. The ability to predict the metastatic proclivity is essential in choosing the optimal treatment. Tumor size and grade, which are frequently used markers in node-negative breast cancer patients, are inadequate markers for prognosis and individualized treatment design. The steps in metastatic progression include angiogenesis, invasion, and changes in adhesion characteristics. We developed a strategy for choosing biomarkers representing these steps in malignant progression to identify patients with occult metastases who will need chemotherapy and spare those women whose tumors have not developed the capacity to spread. To evaluate the added significance of E-cadherin to that of nm23-H1 and angiogenesis in determining metastatic proclivity, we used archival material from 168 node-negative breast cancer patients who were treated with mastectomy without any adjuvant chemotherapy or hormone therapy. Immunohistochemistry was used to detect E-cadherin and nm23-H1 expression, whereas angiogenesis was determined by microvessel count (MVC) after immunohistochemical staining. The median follow-up is 14 years. We found that E-cadherin is better in identifying the poor prognosis patients. The 14-year disease-free survival (DFS) is 84%, 80%, and 56% in patients with high, intermediate, and low E-cadherin. The worst prognosis group using nm23-H1 and MVC as biomarkers has a 14-year DFS of 62%. In this group, if E-cadherin is low, the 14-year DFS is further decreased to 44%. Nm23-H1 and MVC are better in identifying the good prognosis patients. The long-term DFS is >90% if MVC is low or if nm23-H1 is high. Multivariate analysis shows that E-cadherin, nm23-H1, and MVC are more significant prognostic biomarkers than tumor size or grade. Loss of E-cadherin appears to be a latter step in the metastatic progression compared to angiogenesis and the loss of nm23-H1 expression.

Adult↗
PubMed2000

Aspirin for the primary prevention of stroke and other major vascular events: meta-analysis and hypotheses.

BACKGROUND: Aspirin therapy reduces stroke by about 25% for persons with atherosclerotic vascular disease, but the effect in those without clinically apparent vascular disease is distinctly different. OBJECTIVE: To define the effect of aspirin use on stroke and other major vascular events when given for primary prevention to persons without clinically recognized vascular disease. DATA SOURCES AND EXTRACTION: Systematic review of randomized clinical trials and large prospective observational cohort studies examining the relation between aspirin use and stroke in persons at low intrinsic risk. Studies were identified by a computerized search of the English-language literature. DATA SYNTHESIS: Five randomized trials of primary prevention included 52 251 participants randomized to aspirin doses ranging from 75 to 650 mg/d; the mean overall stroke rate was 0.3% per year during an average follow-up of 4.6 years. Meta-analysis revealed no significant effect on stroke (relative risk = 1.08; 95% confidence interval, 0.95-1.24) contrasting with a decrease in myocardial infarction (relative risk = 0.74; 95% confidence interval, 0.68-0.82). The lack of reduction of stroke by aspirin for primary prevention was incompatible with its protective effect against stroke in patients with manifest vascular disease (P = .001). Intracranial hemorrhage was increased by the regular use of aspirin (relative risk = 1.35; P = .03), similarly for both primary and secondary prevention. In 4 large observational studies, self-selected use of aspirin was consistently associated with higher rates of stroke. CONCLUSIONS: The effect of aspirin therapy on stroke differs between individuals based on the presence or absence of overt vascular disease, in contrast with the consistent reduction in myocardial infarction by aspirin therapy observed in all populations. We hypothesize that the effect of aspirin therapy on stroke for persons with major risk factors for vascular disease may be intermediate between a substantial decrease for those with manifest vascular disease and a possible small increase for healthy persons due to accentuated intracranial hemorrhage. When aspirin is given for primary prevention of vascular events, available data support using 75 to 81 mg/d.

Adult↗
PubMed2000

Antiplatelet therapy for preventing stroke in patients with non-valvular atrial fibrillation and no previous history of stroke or transient ischemic attacks.

BACKGROUND: Atrial fibrillation (AF) carries an increased risk of stroke; antiplatelet agents are proven effective for stroke prevention in other settings. OBJECTIVES: The objective of this review was to determine the efficacy and safety of antiplatelet therapy for prevention of stroke in patients with chronic non-valvular AF. SEARCH STRATEGY: We searched the Cochrane Stroke Group Specialised Register of Trials, MEDLINE database (June 1999), and the database of the Antithrombotic Trialists Collaboration, as well as reference lists of relevant articles. SELECTION CRITERIA: All randomized trials comparing antiplatelet therapies to placebo in patients with non-valvular AF and no history of transient ischemic attack (TIA) or stroke. DATA COLLECTION AND ANALYSIS: Trials for inclusion were independently selected by two reviewers who also extracted each outcome and double-checked the data. The Peto method was used for combining odds ratios. All analysis were, as far as possible, "intention-to-treat". Since the published results of two trials included 3-8% of participants with prior stroke or TIA, unpublished results excluding these participants were obtained from the Atrial Fibrillation Investigators. MAIN RESULTS: Among 1680 participants without prior stroke/TIA, randomized to aspirin (N = 838) or placebo in two trials, aspirin was associated with nonsignificantly lower risks of ischemic stroke (OR = 0.71, CI 95% 0. 46 - 1.10), all stroke (OR = 0.70, CI 95% 0.45 - 1.08) all disabling/fatal stroke (OR =0.88, CI 95% 0.48 - 1.58) and the constellation of stroke, MI or vascular death (OR = 0.76, CI 95% 0. 54 - 1.05 ). Considering all randomized participants including those with prior stroke or TIA, reductions in these events by aspirin were consistently smaller and marginally statistically significant: ischemic stroke (OR = 0.77, CI 95% 0.60-1.00), all stroke (OR = 0.76, CI 95% 0.61 - 0.93), all disabling/fatal stroke (OR = 0.87, CI 95% 0.64 - 1.19) and the combined outcome (OR = 0.79, CI 95% 0.64 - 0. 99). No increase in major hemorrhage was seen, but the number of hemorrhagic events was small. REVIEWER'S CONCLUSIONS: Considering all randomized data, aspirin modestly (by about 20%) reduces stroke and major vascular events in nonvalvular AF. For primary prevention among AF patients with an average stroke rate of 4.5%/year, about 10 strokes would be prevented yearly for every 1000 given aspirin.

Atrial Fibrillation↗
PubMed2000

Oral anticoagulants for preventing stroke in patients with non-valvular atrial fibrillation and no previous history of stroke or transient ischemic attacks.

BACKGROUND: Non-valvular atrial fibrillation (AF) is associated with an increased risk of stroke. OBJECTIVES: The objective of this review was to characterize the efficacy and safety of oral anticoagulation (OAC) with vitamin K antagonists for the primary prevention of stroke in patients with chronic AF. SEARCH STRATEGY: We searched the Cochrane Stroke Group Specialised Register of Trials (June 1999), MEDLINE database, and the database of the Antithrombotic Trialists Collaboration, as well as reference lists of relevant articles. SELECTION CRITERIA: All randomized controlled trials comparing the value of OAC versus control in patients with non-valvular chronic atrial fibrillation and no history of transient ischemic attack (TIA) or stroke. DATA COLLECTION AND ANALYSIS: Trials for inclusion were independently selected by two reviewers who also extracted each outcome and double-checked the data. The Peto method was used for combining odds ratios. All analysis were, as far as possible, "intention-to-treat". Since the published results of four trials included 3-8% of participants with prior stroke or TIA, unpublished results excluding these participants were obtained from the Atrial Fibrillation Investigators. MAIN RESULTS: Of 2313 participants without prior cerebral ischemia from five trials, about half (n = 1154) were randomized to adjusted-dose OAC with an estimated mean INRs ranging between 2.0-2.6 during 1.5 years/participant average follow-up. Participant features and study quality were similar between trials. OAC was associated with large, highly statistically significant reductions in ischemic stroke (OR = 0.34, 95% CI 0.23 - 0.52), all stroke (OR = 0.39, 95% CI 0.26 - 0. 59), all disabling or fatal stroke (OR = 0.47, 95% CI 0.28 - 0.80), and the combined endpoint of all stroke, MI or vascular death (OR = 0.56, 95% CI 0.42 - 0.76). The observed rates of intracranial and extracranial hemorrhage not significantly increased by OAC therapy, but confidence intervals were wide. REVIEWER'S CONCLUSIONS: Adjusted-dose OAC (achieved INRs between 2-3) reduces stroke as well as disabling/fatal stroke for patients with nonvalvular AF, and these benefits were not substantially offset by increased bleeding among participants in randomized clinical trials. Limitations include relatively short follow-up and imprecise estimates of bleeding risks from these selected participants. For primary prevention in AF patients who have an average stroke rate of 4%/year, about 25 strokes and about 12 disabling fatal strokes would be prevented yearly for every 1000 given OAC.

Anticoagulants↗
PubMed2000

Expression of fos and jun proto-oncogenes in benign versus malignant human uterine tissue.

OBJECTIVE: The objective of this study was to evaluate expression of fos and jun proto-oncogenes in benign human uterine tissue compared with malignant uterine tissue. METHODS: Forty-two endometrial tissue specimens were obtained at the time of hysterectomy. Tissue samples from different phases of the menstrual cycle and from postmenopausal patients were stained using immunohistochemical methods to detect Fos and Jun proteins, estrogen and progesterone receptor status, and Ki67 (detects a nuclear antigen associated with proliferating cells). Tissue was examined microscopically for nuclear staining in endometrial epithelium and stroma. The endometrium was based on the patient's last menstrual period, pathologic dating, and proliferative versus nonproliferative status as determined by Ki67. Benign and malignant specimens were subjected to Northern blot analysis to evaluate levels of expression of c-fos, c-jun, and jun-B mRNA. The pattern of c-fos mRNA expression in malignant samples was further evaluated using in situ hybridization. RESULTS: In proliferative, secretory, postmenopausal, and progesterone-influenced, uterine specimens immunohistochemically stained and examined, the endometrial and stromal nuclei stained for both Fos and Jun in varying intensities. However, no pattern was found in the variation of intensity according to the phase of the endometrium. Similarly, in malignant and benign endometrial tissue examined by Northern blot and in situ hybridization analyses, expression of proto-oncogene mRNAs was readily detectable, but no statistical correlation between type of tissue examined, grade of adenocarcinoma, and stage of endometrial cancer was found in this study. CONCLUSIONS: In rodent models, control of uterine cell proliferation is related to change in expression of fos and jun proto-oncogenes. Our results indicate that hormonal control is likely to be different in human endometrium and probably involves genes other than the proto-oncogenes under study. Expression of Fos and Jun do not correlate with endometrial cancer stage and grade.

Adenocarcinoma↗
PubMed2000

Primary prevention studies and the healthy elderly: evaluating barriers to recruitment.

Although primary prevention studies are important tools in helping the healthy elderly stay healthy, recruiting from a community-based cohort of healthy elderly individuals for a primary prevention study involves numerous barriers. To better identify and understand these barriers, we conducted and evaluated a comprehensive recruitment strategy for a primary prevention study testing aspirin in an HMO population. In the recruitment phase, we identified healthy individuals (65 years of age or older) who were members of a large, group-model HMO in Oregon and Washington, and used computerized medical database screening, statistical sampling, health plan mailings, e-mail communication with primary care providers, and the experience of a well-established research clinic in an effort to enroll health elderly in this primary prevention trial. Among a random sample of 47,453 eligible patients over the age of 65, 44% responded to recruitment efforts, but only 3% were enrolled--an overall yield of slightly less than 2%. To evaluate these results, we then conducted focus groups with 225 randomly selected "eligible refusers." We determined that healthy elders were hesitant to give up their choice to use aspirin, unwilling to travel to the research center, and reluctant to risk their tenuous hold on good health to participate in a study of primary prevention. Awareness of these attitudes is an indispensable step toward designing effective recruitment strategies for primary prevention studies involving the healthy elderly.

Aged↗
PubMed2000

Combined PI-DAPI staining (CPD) reveals NOR asymmetry and facilitates karyotyping of plant chromosomes.

This paper presents a preparative and staining procedure for plant mitotic chromosomes that uses a combination of PI (propidium iodide) and DAPI (4',6-diamidino-2-phenylindol) and which reveals a pattern of high-affinity regions for these fluorochromes. Nucleolar organiser regions (NORs), telomeres and centromeric regions exhibit high PI affinity (red), whereas other chromosomal regions exhibit high affinity for either PI (red) or DAPI (blue). NOR-bearing and other chromosomes are readily distinguished, facilitating karyotyping. The dual staining pattern was observed in all the plants tested. Aspects of NOR size, number and occurrence are discussed. A karyotype of rice metaphase chromosomes is presented, based on their fluorescent banding patterns.

Centromere↗
PubMed2000

Sex and other predictors of intra-aortic balloon counterpulsation-related complications: prospective study of 1119 consecutive patients.

BACKGROUND AND OBJECTIVE: Intra-aortic balloon counterpulsation (IABC) complication rates remain significant despite technical advances that have simplified and expanded its use. Previous reports implicated patient height, diabetes, or peripheral vascular disease as risk factors. However, these studies were small and not prospective. Therefore a prospective study at one high-volume center was conducted examining the complications associated with IABC and the role of sex and other risk factors in the current era. METHODS: The study prospectively evaluated 1174 consecutive percutaneous IAB insertions in 1119 patients between 1993 and 1997. Major complications were defined as embolism or limb ischemia requiring surgery; bleeding requiring transfusion or surgery; systemic infection; balloon rupture; or death from one of these causes. Minor complications were defined as limb ischemia or pulse loss resolving without surgery or after IAB removal or bleeding not requiring transfusion or surgical intervention. All variables were analyzed with univariate and stepwise multivariate analysis. RESULTS: Data were collected on 1119 patients (727 men and 392 women) with a mean age of 65 +/- 11 years. The prevalence of diabetes, hypertension, and peripheral vascular disease was 27%, 52%, and 8%, respectively. Complications occurred in 166 patients (15%) and a major complication occurred in 126 (11%) of the 1119 patients. Multivariate logistic regression analysis was done with demographic, clinical, and procedural variables in a cohort of 1106 patients. The analysis identified peripheral vascular disease (relative risk [RR] 4.1), female sex (RR 2.3), and body surface area (RR 0.26 per m(2)) as independent predictors of a major complication. In addition, cardiac index (RR 0.7) was also identified as an independent predictor of any or major complications in a subset of 915 patients. In 754 high-risk patients (women or patients with peripheral vascular disease, diabetes, cardiac index <2.2 L/min/m(2), or body surface area <1.8 m(2)), 114 major complications occurred (15%) compared with 8 (3%) among 278 non-high-risk patients (P <.0001). CONCLUSIONS: The current complication rate associated with IABC remains significant. Advances in IAB technology need to focus on the high-risk subset of patients that includes women, smaller patients, and those with peripheral vascular disease.

Aged↗
PubMed1999

Antithrombotic therapy to prevent stroke in patients with atrial fibrillation: a meta-analysis.

PURPOSE: To characterize the efficacy and safety of anticoagulants and antiplatelet agents for prevention of stroke in patients with atrial fibrillation. DATA SOURCES: Randomized trials identified by using the search strategy developed by the Cochrane Collaboration Stroke Review Group. STUDY SELECTION: All published randomized trials testing antithrombotic agents to prevent stroke in patients with atrial fibrillation. DATA EXTRACTION: Data on interventions, number of participants, duration of exposure and occurrence of all stroke (ischemic and hemorrhagic), major extracranial bleeding, and death were extracted independently by two investigators. DATA SYNTHESIS: Sixteen trials included a total of 9874 participants (mean follow-up, 1.7 years). Adjusted-dose warfarin (six trials, 2900 participants) reduced stroke by 62% (95% CI, 48% to 72%); absolute risk reductions were 2.7% per year for primary prevention and 8.4% per year for secondary prevention. Major extracranial bleeding was increased by warfarin therapy (absolute risk increase, 0.3% per year). Aspirin (six trials, 3119 participants) reduced stroke by 22% (CI, 2% to 38%); absolute risk reductions were 1.5% per year for primary prevention and 2.5% per year for secondary prevention. Adjusted-dose warfarin (five trials, 2837 participants) was more efficacious than aspirin (relative risk reduction, 36% [CI, 14% to 52%]). Other randomized comparisons yielded inconclusive results. CONCLUSIONS: Adjusted-dose warfarin and aspirin reduce stroke in patients with atrial fibrillation, and warfarin is substantially more efficacious than aspirin. The benefit of antithrombotic therapy was not offset by the occurrence of major hemorrhage among participants in randomized trials. Judicious use of antithrombotic therapy, tailored according to the inherent risk for stroke, importantly reduces stroke in patients with atrial fibrillation.

Anticoagulants↗
PubMed1999

Reduction in ischemic vascular complications with a hydrophilic-coated intra-aortic balloon catheter.

Hydrophilic coatings improve the handling characteristics of angioplasty equipment, but until recently this technology has not been available for intra-aortic balloon (IAB) catheters. To determine whether a new hydrophilic coating is associated with a reduction in IAB-related complications, we prospectively evaluated 188 patients undergoing insertion of this new IAB catheter. Complications related to IAB insertion were recorded and compared to data from 682 patients previously treated with an uncoated IAB catheter of the same shaft diameter and balloon size. By multivariate analysis the hydrophilic-coated IAB catheter was associated with a 72% reduction in ischemic vascular complications (relative risk 0.28, 95% CI 0.08-0.96, P= 0.04). There were also trends toward reductions in IAB rupture and the need for vascular surgical repair for bleeding or ischemia. While further investigation is warranted, hydrophilic coatings that reduce the coefficient of friction during IAB catheter insertion may also reduce subsequent ischemic vascular complications.

Aged↗
PubMed1999

Left atrial diameter in nonvalvular atrial fibrillation: An echocardiographic study. Stroke Prevention in Atrial Fibrillation Investigators.

BACKGROUND: The left atrium (LA) is usually enlarged in patients with nonvalvular atrial fibrillation (AF), but factors associated with LA diameter are incompletely defined. METHODS AND RESULTS: This transthoracic echocardiographic cohort study includes 3465 participants with nonvalvular AF in 3 multicenter clinical trials. LA diameter determined by M-mode echocardiography was correlated with clinical and echocardiographic features by cross-sectional multivariate regression analyses. The mean LA diameter was 47 +/- 8 mm, on average 6 mm larger in those with AF at the time of echocardiography than in those with sinus rhythm (48 vs 42 mm, P <. 001). Patient age and body weight were independently predictive of LA diameter (P <.0001), but sex, body surface area, and body mass index were not. The estimated independent contribution of atrial rhythm to LA diameter was approximately 2.5 mm. Prolonged duration of AF, left ventricular dilatation and increased muscle mass, mitral regurgitation, annular calcification, and hypertension were additional independent predictors of LA diameter. CONCLUSIONS: Multiple factors appear to contribute to LA enlargement in patients with nonvalvular AF, including the presence and persistence of the dysrhythmia.

Age Factors↗
PubMed1999

Factors associated with ischemic stroke during aspirin therapy in atrial fibrillation: analysis of 2012 participants in the SPAF I-III clinical trials. The Stroke Prevention in Atrial Fibrillation (SPAF) Investigators.

BACKGROUND AND PURPOSE: Nonvalvular atrial fibrillation (AF) is a strong, independent risk factor for stroke, but the absolute rate of stroke varies widely among AF patients, importantly influencing the potential benefit of antithrombotic prophylaxis. We explore factors associated with ischemic stroke in AF patients taking aspirin. METHODS: We performed multivariate logistic regression analysis of 2012 participants given aspirin alone or in combination with low, inefficacious doses of warfarin in the Stroke Prevention in Atrial Fibrillation I-III trials followed for a mean of 2.0 years, during which 130 ischemic strokes were observed. RESULTS: Age (relative risk [RR]=1.8 per decade, P<0.001), female sex (RR=1.6, P=0.01), history of hypertension (RR=2.0, P<0.001), systolic blood pressure >160 mm Hg (RR=2.3, P<0.001), and prior stroke or transient ischemic attack (RR=2.9, P<0.001) were independently associated with increased stroke risk. Regular consumption of >/=14 alcohol-containing drinks per week was associated with reduced stroke risk (adjusted RR=0.4, P=0.04). Among SPAF III participants, estrogen hormone replacement therapy was associated with a higher risk of ischemic stroke (adjusted RR=3.2, P=0.007). With the use of these variables, a risk stratification scheme for primary prevention separated participants into those with high (7.1%/y, 22% of the cohort), moderate (2.6%/y, 37% of the cohort), and low (0.9%/y, 41% of the cohort) rates of stroke. Ischemic strokes in low-risk participants were less often disabling (P<0.001). CONCLUSIONS: Patients with AF who have high and low rates of stroke during treatment with aspirin can be identified. However, validation of our risk stratification scheme is necessary before it can be applied with confidence to clinical management. Postmenopausal estrogen replacement therapy and moderate alcohol consumption may additionally modify the risk of stroke in AF, but these findings require confirmation.

Aged↗
PubMed1998

Acute coronary syndromes in the United States and United Kingdom: a comparison of approaches. The Antithrombotic Therapy in Acute Coronary Syndromes Research Group.

BACKGROUND: Patients with coronary artery disease are managed differently in different countries. HYPOTHESIS: These variations in patient management may affect clinical outcome, a possibility that should be taken into consideration in multicenter studies. METHODS: In a binational, 3 months study of antithrombotic treatment of patients with unstable angina and non-Q-wave infarction (ATACS), we compared the experience in the four enrollment centers in the United States (US) with the three centers in the United Kingdom (UK). The 59 US patients and the 299 UK patients were similar with regard to age, rates of prior revascularization, prior positive exercise tests, medication use, and aspirin use. RESULTS: US patients were more commonly women (45 vs. 28%), diabetic (30 vs. 4%), or hypertensive (52 vs. 31%), and had a prior coronary angiogram (30 vs. 18%). After enrollment, coronary angiography was performed more frequently in the US than in the UK (61 vs. 22%). Although the distribution of coronary disease was similar, revascularization without recurrent angina (19 vs. 4%, p < 0.001), or following recurrent angina (8 vs. 3%), was significantly more frequent in the US. Combined primary end points (recurrent angina, myocardial infarction, or death) did not differ between US (29%) and UK (25%) patients. CONCLUSION: Therefore, international studies of acute coronary disease need to account for different treatments in different countries. These differences, in the small ATACS study, did not have a major impact on the composite primary outcome variables.

Adult↗
PubMed1998

Bleeding Complications and INR Control of Combined Warfarin and Low-Dose Aspirin Therapy in Patients with Unstable Angina and Non-Q-Wave Myocardial Infarction.

The purpose of this study was to compare bleeding complications in patients with non-Q-wave myocardial infarction and unstable angina receiving combination therapy with aspirin plus warfarin versus aspirin alone. A post-hoc analysis was performed on patients enrolled in the Antithrombotic Therapy in Acute Coronary Syndrome (ACTACS) study, which was a prospective, randomized, multicenter trial of antithrombotic therapy in unstable angina or non-Q-wave myocardial infarction. A total of 358 patients admitted within 48 hours of chest pain were randomized to antithrombotic therapy with either (1) aspirin alone or (2) aspirin (162.5 mg) plus heparin followed by aspirin plus warfarin, and were prospectively followed up for 12 weeks. Major and minor bleeding episodes, hemoglobin levels, and prothrombin times or INR levels were prospectively recorded. Major bleeding episodes were subclassified as relating to CABG/PTCA or not. The rate of major bleeding complications not associated with CABG or PTCA was 2.0%, and did not differ between therapy assignments. Among 55 patients undergoing CABG, 29 (53%) required transfusion of two or more units of blood. Minor bleeding was also infrequent (2.8%). All patients with minor bleeding had a full clinical recovery, and only one patient with a major bleed resulted in minor disability. Warfarin was well managed, with 50% of INRs falling between 1.9 and 2.7. Combination therapy with low-dose aspirin and warfarin (INR mean 2.5) produces an insignificant rise in the incidence of major and minor bleeding. These events are infrequent and do not usually result in major disability. The effect of longer duration combination therapy remains to be determined.

Journal Article↗
PubMed1997

Prospective Comparison of Patient Characteristics and Outcome of Non-prior Aspirin Users versus Aspirin Users with Unstable Angina or Non-Q-Wave Myocardial Infarction Treated with Combination Antithrombotic Therapy.

The objective of this study was to determine if aspirin users presenting with acute coronary syndromes are at higher risk for subsequent clinical events. In a trial evaluating combination antithrombotic therapy in resting angina or non-Q-wave myocardial infarction (MI), patients were prospectively dichotomized on admission into nonprior versus recent aspirin users. Then 105 nonprior users and 144 users were randomized to treatment with aspirin plus heparin/warfarin for 12 weeks. Recurrent myocardial ischemia occurring during the 12-week follow-up period was defined as recurrent angina (with electrocardiographic changes or prompting coronary revascularization), MI, or death. Prior aspirin users had a significantly higher incidence of previous MI, prior bypass grafting, beta-blocker use, or hypertension (p </= 0.003) and were more likely to present with unstable angina as opposed to non-Q-wave MI. (p </= 0.008). The cumulative probability of recurrent ischemic endpoints for nonprior versus recent users was 10% versus 21% at 14 days (log rank p = 0.03), and 19% versus 29%, at 12 weeks (p = 0.06). Using the Cox model, adjusting for variables significantly associated with outcome, aspirin use remained a significant predictor of 14-day outcome (p = 0.04) but not of 12-week outcome (p = 0.06). In conclusion, even after adjusting for significant differences in baseline variables, aspirin users presenting with rest angina or non-Q-infarction have a worse short-term prognosis in spite of maximal medical therapy.

Journal Article↗