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At least 919 records · Page 51Linked to original sources
PubMed1978

Comparison of therapy in severe systemic lupus erythematosus employing stratification techniques.

Randomized studies, attempting to clarify the role of combined azathioprine and prednisone therapy versus prednisone alone in severe systemic lupus erythematosus have sustained rather than mollified a clinical controversy. No differences have been detected in some studies, while others have appeared to show benefit with addition of azathioprine. The present study suggests that neither small random trials nor uncorrected clinical experience can be expected to provide truly comparable control groups in conditions as variable as systemic lupus, but that stratification techniques can yield relatively similar groups. Patients meeting different entry characteristics are demonstrated to come to different outcomes. Depending upon the specifications of a subgroup, one therapy or another appears better.

Azathioprine↗
PubMed1982

Clinical factors related to the presence of estrogen receptors in breast cancer: a prognostic stratification analysis.

The techniques used for determination of hormone receptors have provided a biochemical basis to the concept of hormone-dependence in breast cancer. By medical experience clinical factors were established for determination of hormonal treatment in breast tumors. The criteria used need now to be re-evaluated in terms of hormone receptor contents. We analysed a group of 155 patients with histologically confirmed breast carcinoma in which estradiol receptor determination was performed. Of these tumors 54% had more than 10 fmol of estradiol per mg protein. Menopause, advanced age, late first childbirth, obesity, early menopause and nuliparity were associated, in that order, with the presence of estrogen receptors in breast tumors. Prognostic stratification analysis brought out polar groups of estrogen receptor contents. Young, premenopausal women with children had only 16% estrogen receptor-positive tumors. Postmenopausal women, either without children or with late first childbirth had as much as 81% of estrogen receptor containing tumors. Clinical variables related to the presence of estrogen receptor positive tumors in the breast cancer population were coincident to risk factors for breast cancer in the healthy population. Possible implications of this coincidences are discussed.

Adult↗
PubMed1982

[Traumatic rupture of the thoracic aorta with stratification of the esophageal and gastric wall].

An observation of a delayed posttraumatic rupture of the thoracic aorta attended by acute stratification of the esophageal and gastric wall by blood is described. The patient who had been strongly hit into the thorax in a car accident died of acute massive blood loss 10 days after the trauma. Breaks in the aortal intima occurring at the moment of the trauma may be conducive to the aortal rupture.

Adult↗
PubMed1978

[Embryonal development of the brain of the shark Scyliorhinus canicula (L.). II. The optic tectum and its stratification].

The stratification of the optic tectum of the shark Scyliorhinus canicula is comparable to patterns of other vertebrates. Thus it is possible to homologize part of the cortex layers with those described by P. RAMON (1896) and HUBER & CROSBY (1933b). 1. As for other vertebrates, it makes sense to collect the large number of zones (layers) into three groups: periventricular, central and superficial. 2. Ramon's periventricular zones 1--3 are distinct; fibrous zone 4 and cellular zone 5 are partially mixed. The central zones (6, 7) are mixed. All superficial zones are recognized, with the exception of zone 14, which was not found. 3. The trigeminal mesencephalic nucleus develops in the early embryo.

Animals↗
PubMed1994

Other special considerations in assessing DC-ART: The need for patient stratification.

Given the heterogeneity of rheumatoid arthritis (RA), even in disease of the same duration, it seems likely that some therapeutic regimens will satisfy DC-ART criteria to different degrees in different strata of patients with RA. Since it entails its own problems, it is recommended that the value and feasibility of stratification be evaluated before any attempt to design a DC-ART trial.

Antirheumatic Agents↗
PubMed1995

Stratification of mortality risk for renal artery surgery.

Seventy consecutive operations involving the renal arteries were reviewed to identify factors linked to perioperative mortality. Aortorenal bypass (n = 29), endarterectomy (n = 12), extraanatomic bypass (n = 12), thrombectomy (n = 4), and reimplantation (n = 13) were associated with a 16% perioperative mortality that was often secondary to multisystem organ failure. Patients who died exhibited a higher serum creatinine (3.4 vs 2.1 mg/dL; P < 0.05). Stratification of patients by risk revealed higher American Society of Anesthesiologists (ASA) (P < 0.005) and modified Acute Physiology Score, and Chronic Health Evaluation (APACHE II) (P < 0.02) score among patients who died. Higher mortality was also observed after bilateral renal artery operations (31% vs 5%; P < 0.005) or concomitant mesenteric revascularization (37% vs 12%; P < 0.05), but not simultaneous aortic procedures (18% vs 11%; P = NS). Bilateral operation (P < 0.0001), age (P < 0.001), and ASA class (P < 0.01) were independent predictors of mortality according to multivariate analysis. Because of higher mortality in these specific situations, modification or limitation of operative scope may be appropriate.

APACHE↗
PubMed1994

Pre-discharge atrial pacing test in evaluation of risk stratification after uncomplicated myocardial infarction.

Right atrial pacing (RAP) using three pacing stages (I: 100 BPM/5 min; II: 120 BPM/5 min; III: 140 BPM/5 min) was performed for residual myocardial ischemia, hypotensive response and related prognostic significance in 55 uncomplicated acute myocardial infarction (AMI) patients. We aimed to clarify whether early risk stratification and jeopardized myocardium score, calculated using pacing results, could predict disease severity and future major cardiac events during long-term follow-up. During RAP testing, 24 patients displayed negative and 31 patients positive RAP. The positive RAP group had a significantly higher incidence of multivessel disease, higher jeopardized myocardium scores and left ventricular end-diastolic pressure than the negative RAP group. As expected, according to pacing response the disease severity score also showed a significant difference. During the one-year follow-up, there were three recurrent angina attacks, reinfarction and two congestive heart failures in the negative RAP group. In the positive RAP group, four died, six had new or recurrent myocardial infarctions and six developed congestive heart failure. Only six patients in the positive RAP group carried the critical risk, four suffered from recurrent angina, two developed reinfarction, three developed congestive heart failure, and two died. Total major cardiac events in the positive RAP group appeared to significantly increase compared to those in the negative RAP group. Our results show that early RAP with three pacing stages is useful in predicting subsequent major cardiac events after uncomplicated myocardial infarction. We also observed that hypotensive response during positive RAP represents the best predictor of critical risk requiring further invasive studies. We believe that RAP is justified for risk strategy.

Aged↗
PubMed1994

Mutation profiles of phenylketonuria in Quebec populations: evidence of stratification and novel mutations.

Independent phenylketonuria (PKU) chromosomes (n = 109) representing 80% of a proband cohort in Quebec province carry 18 different identified mutations in 20 different mutation/haplotype combinations. The study reported here, the third in a series on Quebec populations, was done in the Montreal region and predominantly on French Canadians. It has identified three novel mutations (A309D, D338Y, and 1054/1055delG[352fs]) and one unusual mutation/RFLP haplotype combination (E280K on Hp 2). The relative frequencies and distribution of PKU mutations were then compared in three regions and population subsets (eastern Quebec, French Canadian; western Quebec, French Canadian; and Montreal, non-French Canadian). The distributions of the prevalent and rare mutations are nonrandom and provide evidence for genetic stratification. The latter and the presence of eight unusual mutation/haplotype combinations in Quebec families with European ancestries (the aforementioned four and M1V, I65T, S349P, and R408W on Hp 1) corroborate demographic and anthropologic evidence, from elsewhere, for different origins of French Canadians in eastern and western Quebec.

DNA Mutational Analysis↗
PubMed1994

The social stratification of aging and health.

The way health varies with age is importantly stratified by socioeconomic status (SES)--specifically, education and income. Prior theory and cross-sectional data suggest that among higher SES persons the onset of health problems is usually postponed until rather late in life, while health declines are prevalent in lower SES groups by middle age. Thus, SES differences in health are small in early adulthood, but increase with age until relatively late in life, when they diminish due to selection or greater equalization of health risks and protections. The present paper strengthens our causal and interpretive understanding of these phenomena by showing: (1) that results previously reported for indices of SES hold separately for education and income; (2) that the interaction between age and SES (i.e., education or income) in predicting health can be substantially explained by the greater exposure of lower SES persons to a wide range of psychosocial risk factors to health, especially in middle and early old age, and, to a lesser degree, the greater impact of these risk factors on health with age; and (3) that results (1) and (2) generally hold in short-term longitudinal as well as in cross-sectional data. Implications for science and policy in the areas of aging, health, and social stratification are discussed.

Activities of Daily Living↗
PubMedDate not supplied

[Therapeutic trials in Alzheimer disease. Selection--recruitment and stratification].

Therapeutic trials conducted in Alzheimer's disease have benefited from the standardization of diagnostic criteria based on internationally recognized scales (DSM III-R, NINCDS-ADRDA) which ensure more valid inclusions. Well specified exclusion criteria are also of the utmost importance, in particular depression, vascular dementia and concomitant psychotropic drugs. Cognitive and/or functional scales allow an appreciation of the severity of the disease. Due to the heterogeneity of Alzheimer's disease stratification methods on identified prognostic factors i.e. aphasia, extrapyramidal symptoms should be performed. Selection of responders during an enrichment phase has still to be discussed. Multicentric studies become imperative because of the large number of patients required and the difficulties in selecting the adequate patients. These raise the issues of investigators' experience, coordination and between center variability.

Alzheimer Disease↗
PubMed1993

[Clonal myelodysplasia: prognostic stratification and therapeutic possibilities].

Myelodysplastic syndromes represent an entire group of clonal panmyelopathies with very distinct evolutionary pathways. Their common denominator, however, is a self-maintained functional failure of the myeloid hemopoiesis which tends to evolve into severe non-lymphoid leukemia (SNLL) in 20-30% of the cases. First, the prognostic value of each the following is reviewed: the morphological classification F.A.B., the stratification system for "Bournemouth group", the abnormal placement of immature myeloid precursors (ALIP) in bone marrow, and cytogenetic changes. Second, the therapeutic potential for each of the following is assessed: vitamin and support treatments; suprarenal steroids; conventional androgens and danazol; agents of cellular differentiation (cytosine arabinoside in low doses, retinoid acids, vitamin D3, etc.). Finally, the role of aggressive chemotherapies (in succession or unrelated to marrow transplant) in the eradication of myelodysplastic clone or post-myelodysplasia SNLL is examined.

Humans↗
PubMed1995

[The usefulness of noninvasive diagnostic methods in postinfarct prognostic stratification].

We have studied 455 consecutive patients with acute myocardial infarction to assess the early and mid-term prognostic value of clinical and laboratory findings in the acute (i.e. Killip classification, arterial PO2, echocardiographic extent of necrotic area) and subacute phase (exercise test, ambulatory ECG). Results showed that clinical examination, blood gas analysis and two-dimensional echocardiography have a high predictivity for in-hospital risk stratification. In particular, two-dimensional echocardiography showed that patients with diffuse wall motion abnormalities had a worse prognosis during the follow-up. Exercise test and, to a lesser extent, ambulatory ECG have well identified patients at risk for new coronary events.

Adult↗
PubMed1995

[The risk of dengue transmission: a space for stratification].

The emergence of dengue fever as a public health problem in the Americas is increasing. Its rapid spread in the region and the geographical dissemination of dengue infection has not been followed by a corresponding input of financial, human and technical resources necessary to control dengue fever epidemics. This situation compelled to the analysis of dengue transmission in Mexico with the objective of designing a strategy of dengue fever surveillance based on the stratification of transmission risks taking into account geographical variables like climate, rain precipitation, mean annual temperature and altitude, as well as socio-demographical variables like population density and socio-economic level. This strategy will permit the efficient use of the scant resources available for control, although the impact of dengue transmission is yet to be evaluated.

Adolescent↗
PubMed1996

Risk stratification after acute myocardial infarction: which studies are best?

The prognosis for a patient who has survived an acute myocardial infarction depends on three general prognostic factors: (1) residual left ventricular function, (2) remaining viable myocardium at risk (residual ischemia), and (3) presence of substrate for the development of malignant arrhythmias. Multiple clinical and historical factors predict the presence of one or more of these prognostic indicators. Electrocardiographic exercise treadmill testing needs to be done in all patients with uncomplicated infarctions. Guidelines of the American College of Cardiology/American Heart Association Task Force are recommended for risk stratification in most patients after acute myocardial infarction.

Arrhythmias, Cardiac↗
PubMed1996

Alternative approaches to the prognostic stratification of mild to moderate primary vesicoureteral reflux in children.

PURPOSE: We compared the prognostic stratification of primary vesicoureteral reflux by performing staging voiding cystourethrography in all children with a urinary tract infection or only in those with renal scarring on 99mtechnetium-dimercapto-succinic acid (DMSA) scintigraphy. MATERIALS AND METHODS: Staging voiding cystourethrography and DMSA scintigraphy were performed in 105 children with a urinary tract infection and reflux persistence was assessed by radionuclide cystography after a 2-year followup. RESULTS: Staging voiding cystourethrography revealed no reflux in 51 children (DMSA positive in 3), grades I to II reflux in 21 (DMSA positive in 6) and grade III reflux in 33 (DMSA positive in 19). On followup radionuclide cystography no new reflux was detected, and it was no longer demonstrated in 23 children (8 with grade III and 15 with grades I to II reflux). The finding of grade III reflux on staging voiding cystourethrography had a 76% positive and a 92% negative value for predicting persistent reflux with an 87% predictive accuracy. Limiting the evaluation of voiding cystourethrography data to the 28 children with a positive DMSA scan the combination of renal scarring and grade III reflux had an 84% positive and an 83% negative predictive value with 83% accuracy. This approach would have prevented 77 children from having to undergo voiding cystourethrography. CONCLUSIONS: Performance of staging voiding cystourethrography exclusively in children with renal scarring on a DMSA scan resulted in predictive accuracy that was close to what was achieved by performing voiding cystourethrography in all children with a urinary tract infection. To be able to limit cystourethrography to a select population could prove to be cost-effective.

Case-Control Studies↗
PubMed1996

The case for cardiac troponin T: marker for effective risk stratification of patients with acute cardiac ischemia.

Availability of markers such as cardiac troponin T (cTnT) has brought new insights into ischemic heart disease (IHD). cTnT is a distinct protein that differs from other markers in biological function, molecular mass, and cytosolic pool. cTnT has been utilized for diagnosis of acute myocardial infarction (AMI) and risk stratification of patients with IHD. For AMI diagnosis, cTnT showed high sensitivity (94-100%) but generally lower specificity (46-99%), possibly because of increases in non-AMI patients with minor myocardial damage. Outcome studies have demonstrated that IHD patients with increased cTnT are at significantly greater risk for cardiac events; revascularization in patients with increased cTnT may improve outcome. Estimated costs for batched ES 300 cTnT results and for a cTnT rapid assay run "on demand" were $17.48 and $21.65, respectively. cTnT currently has no specific common procedure test code; expected reimbursement is $18.32 for the ES 300 and is not established for the rapid assay.

Biomarkers↗
PubMed1996

[Risk stratification following myocardial infarct].

In recent decades, early mortality of acute myocardial infarction has decreased from above 30% to below 10%. Many survivors of acute myocardial infarction are at increased risk for cardiac death and/or nonfatal recurrent ischemic events. This has not changed with the introduction of thrombolysis. How can high risk patients be identified who would benefit from coronary revascularization and/or from antiarrhythmic treatment? Based on clinical findings such as a large infarction, infarction of the anterior wall, congestive heart failure, cardiogenic shock during the acute phase, post-infarct angina and a history of previous infarctions, high risk patients who should undergo coronary angiography and--if feasible--revascularization can be defined. Patients with symptomatic arrhythmias should receive medical or interventional antiarrhythmic treatment. All patients who are clinically considered not to be at high risk should undergo risk stratification with signal averaged ECG, non-invasive stress testing and non-invasive quantification of left ventricular function. In the presence of late potentials, ischemia during stress testing and impaired left ventricular function, further evaluation with Holter ECG or an electrophysiologic study and coronary angiography is indicated. In infarct survivors over 75 years old, the therapeutic goal is improvement of quality of life, i.e. relief of symptoms, rather than improvement of prognosis. Invasive procedures should therefore be considered only in individual patients. However, in all postinfarct survivors the assessment and treatment of cardiovascular risk factors and secondary medical prevention is mandatory.

Adult↗
PubMed1995

Risk stratification for malignant arrhythmic events in patients with an acute myocardial infarction: role of an open infarct-related artery and the signal-averaged ECG.

BACKGROUND: There is increasing evidence that an open infarct-related artery results in increased electrical stability of the heart and that this effect is at least in part responsible for the favorable outcome of these patients. In the thrombolytic era the optimal strategy for risk stratification remains controversial. This study examined the predictors of serious arrhythmic events during the first year after myocardial infarction. METHODS: A total of 222 patients with acute myocardial infarction, 41.4% of whom were treated with thrombolysis, were studied. At hospital discharge, signal-averaged electrocardiography was performed on 196 subjects and Holter monitoring on 200. One hundred and ninety-seven patients underwent coronary angiography. Left ventricular ejection fraction was determined in 201 subjects. RESULTS: An open infarct-related artery was documented in 106 patients. The incidence of late potentials was 34% (66 patients). Twenty-four patients (10.8%) had an arrhythmic event during follow-up (sudden death in seven, sustained ventricular tachyarrhythmias in 15, unexplained syncope in two). Signal-averaged electrocardiography had a sensitivity of 94% and a specificity of 72% for prediction of arrhythmic events. An occluded infarct-related artery was 78% sensitive and 58% specific, a left ventricular ejection fraction below 40% had a sensitivity of 71% and specificity of 80%, and Holter monitoring was only 38% sensitive and 92% specific. A combination of late potentials plus an occluded infarct-related artery was 68% sensitive and 84% specific. Positive predictive value was low for all variables examined, but could be improved by the combination of several risk factors. The highest positive predictive value was provided by the combination of an abnormal signal-averaged ECG and complex ventricular arrhythmias on ambulatory ECG. On multivariate analysis, in rank order, presence of late potentials, ejection fraction below 40%, high-grade ventricular ectopic activity and an occluded infarct-related artery were predictive of arrhythmic events. CONCLUSION: Among patients surviving an acute myocardial infarction, the occurrence of malignant arrhythmic events can be reliably predicted by the combination of an abnormal signal-averaged ECG, left ventricular dysfunction, complex ventricular arrhythmias on Holter monitoring and an occluded infarct-related artery at the time of hospital discharge.

Action Potentials↗