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PubMed1988

Clinical assessments as predictors of one year survival after hospitalization: implications for prognostic stratification.

In clinical trials measuring the short term survival of patients, prognostic stratification is important to avoid susceptibility bias. Demographic and disease specific clinical features are commonly used to established similarity, but these may not insure prognostic comparability. To identify the generic predictors of one year survival after hospitalization, a cohort of 559 patients admitted to the medical service at New York Hospital was studied. Among all of the clinical and demographic information available at the time of admission, only three were independent predictors of the time until death: functional ability, severity of illness and extent of comorbid disease. The overall one year survival rate was 66%. Six subgroups composed of patients with different combinations of the predictors of prognosis had mortality rates ranging from 97% to 14%. Illness severity was a predictor only in the less functional patients, and only severe comorbidity was associated with a decreased survival after taking into account functional ability and illness severity. Prospective estimates of severity of illness, functional ability and extent of comorbidity can be used to stratify a diverse group of patients according to their probability of one year survival after hospitalization.

Adult↗
PubMed1995

Stratification of vascular risk in hypertension and therapeutic perspective.

Hypertension is a major risk factor for cardiovascular disease and atherosclerosis is the cause of most hypertensive complications. Therefore the detection of preclinical atherosclerosis may contribute to the better identification of hypertensive subjects at high risk of complications. Three main alterations are currently able to be diagnosed noninvasively: calcification, thickening, and stiffening of the arterial walls. Calcification of epicardial coronary arteries can be seen noninvasively by ultrafast computed tomography thanks to its rapid acquisition of image. Coronary calcification of epicardial coronary arteries can be seen noninvasively by ultrafast computed tomography thanks to its rapid acquisition of image. Coronary calcification is typical of atherosclerosis but not of stenosis. Conversely, the absence of calcification eliminates, practically, coronary artery disease as a diagnosis. Coronary calcification is present in only 63% of asymptomatic hypertensive men, suggesting that the degree of coronary atherosclerosis associated with high blood pressure varies among individuals. Wall thickening can be quantified in vivo by automated computerized analysis of ultrasonic images of the far wall intima-media complex of extracoronary vessels. Carotid and femoral wall thickening was observed in hypertensive subjects who had never been treated for hypertension compared to normotensive controls of similar age. Such vascular hypertrophy was not found in all patients, attesting to the disparity of the structural arterial changes within hypertensive subjects. Recent evidence from studies of essential hypertension suggests the lack of association between diffuse wall thickening of carotid or femoral arteries and the presence of atherosclerotic plaque (focal echogenic encroachment) in the same vessel. However, other studies in at-risk subjects suggest that extracoronary wall thickening could be related to the presence of coronary atherosclerosis, and to the incidence of coronary events. Wall stiffening is the third arterial alteration related to the sclerotic component of atherosclerosis. Its evaluation is based on the velocity of pulse wave propagation within the arterial tree or on the ultrasonic (echotracking) assessment of arterial wall distension during the cardiac cycle. Arterial stiffening is increased in the presence of hypertension, and such an increase is potentiated by the presence of other risk factors, such as smoking or hypercholesterolemia. Finally, the detection of early atherosclerosis with the above techniques optimizes the stratification of atherosclerotic risk, and may provide relevant information on comparative effectiveness of various classes of antihypertensive agents.

Antihypertensive Agents↗
PubMed1993

Stratification of the channel domain in neurotransmitter receptors.

Analyses of the ionic pore of ligand-gated ion channels at the amino acid level reveal a structural and functional stratification of the M2 channel domain. Mutations in the equatorial and outer regions affect channel gating, whereas mutations of other amino acid rings alter ionic permeability or selectivity.

Animals↗
PubMed2004

Is hormonal activation during exercise useful for risk stratification in patients with moderate congestive heart failure?

BACKGROUND: We previously demonstrated that A-type natriuretic peptide (ANP) at peak exercise was an independent predictor of cardiac survival. No data are available concerning the predictive value of B-type natriuretic peptide (BNP) at peak exercise. METHODS: One hundred and fifty consecutive stable patients with moderate congestive heart failure (CHF) underwent echocardiography and a cardiopulmonary exercise test. Blood samples were drawn at rest and at peak exercise for the determination of plasma levels of ANP, BNP, and norepinephrine. RESULTS: Exercise significantly increased plasma values of ANP, BNP, and norepinephrine. After a median follow-up period of 1171 days, there were 35 cardiac related deaths. Mortality rates at 1 and 2 years were 4% and 8%, respectively. Independent predictors of cardiac survival were percent of maximal predicted oxygen consumption (RR = 4.8 [2.1-11], P =.002), BNP at rest (RR = 2.5 [1.2-5.6], P =.01), and left atrial diameter (RR = 2.8 [1.2-6.5], P =.02). CONCLUSIONS: In patients with stable, moderate CHF, plasma levels of ANP, BNP, and norepinephrine measured at peak exercise did not improve risk stratification. However, in addition to percent of maximal predicted oxygen consumption and left atrial diameter, plasma level of BNP at rest was an independent predictor of survival in CHF patients with low risk of cardiac events.

Atrial Natriuretic Factor↗
PubMed2006

Recursive partitioning-based preoperative risk stratification for atrial fibrillation after coronary artery bypass surgery.

BACKGROUND: Knowledge of the risk of atrial fibrillation (AF) for patients undergoing coronary artery bypass graft surgery (CABG) can guide decisions about prophylactic therapy. Accordingly, we sought to use tree-based methods to stratify patients into groups that will have similar risk of AF after CABG and informed decision making regarding aggressive prophylaxis of AF. METHODS: We studied 1209 consecutive patients with isolated CABG performed in 1998-1999 at Yale-New Haven Hospital. Patients with preoperative AF were excluded. Tree-based analysis was carried out to stratify patients into similar groups regarding the risk of AF. Relative risks (RRs) and 95% CIs were calculated at each level of stratification. RESULTS: Age was the most important variable. The importance of other risk factors seemed to be different for younger and older patients. Although in the younger age group (< or =60 years) severity of coronary artery disease (RR 2.19, 95% CI 1.12-3.34) followed by hypertension (RR 1.82, 95% CI 1.23-2.68) were important predictors, in the older age subgroups (61-69 and > or =70 years), nothing or only ejection fraction <40% (RR 1.31, 95% CI 1.08-1.59) was important. In the highest-risk group, AF occurrence was 55% and, in the lowest-risk group, it was 10%. In the low-risk groups, aggressive prophylaxis may not be justified in light of the smaller number of events that would be prevented, possible adverse events, and costs. CONCLUSION: Age and variables related to heart disease severity are predictors of AF. The tree-based method may be a useful tool for clinicians who seek to determine who is more or less likely to benefit from aggressive arrhythmia prophylaxis.

Aged↗
PubMed2006

ST-segment depression in non-ST elevation acute coronary syndromes: quantitative analysis may not provide incremental prognostic value beyond comprehensive risk stratification.

BACKGROUND: It is unclear whether quantitative ST-segment assessment can improve risk stratification of unselected acute coronary syndrome (ACS) patients using the validated Global Registry of Acute Cardiac Events (GRACE) risk model. METHODS: In the prospective, multicenter, Canadian ACS Registry, the admission electrocardiogram was evaluated centrally at a blinded core laboratory. Patients with ST-elevation myocardial infarction and other electrocardiogram confounders were excluded. ST depression (ST down) was measured and summed in all leads except aVR. Patients with ST down were divided into 3 groups based on tertiles of cumulative ST down. A multivariable model was developed to examine the independent prognostic value of ST down severity after adjusting for other known prognosticators in the GRACE risk model. RESULTS: Among 2590 patients with non-ST-elevation ACS, more severe ST down was associated with advanced age, higher heart rate and Killip class, elevated creatinine, abnormal biomarkers, higher GRACE risk score, and higher 1-year mortality (all P < .001). After adjusting for these confounding prognosticators, the presence of any ST down remained independently associated with higher 1-year mortality (odds ratio 1.78, 95% CI 1.21-2.63, P = .004). However, the gradient of risk with increasing magnitude of ST down was no longer evident (adjusted odds ratios 1.77, 1.77, 1.81, for ascending tertiles of cumulative ST down, respectively). Moreover, quantitative ST down did not improve the model discrimination for 1-year mortality. The results were similar when the number of leads with ST down or the maximum magnitude of ST down was analyzed, after adjusting for tertiles of GRACE risk score or inhospital revascularization, or using the composite end point of death or myocardial (re)infarction at 1 year. CONCLUSIONS: Greater ST down is associated with other adverse prognosticators across the broad spectrum of non-ST-elevation ACS. Although the presence of any ST down is an independent predictor of 1-year mortality, its quantitative assessment is not as important as its mere presence when studied on the background of comprehensive clinical and biomarker evaluation in a nonclinical trial-based ACS population.

Aged↗
PubMed2006

Comparison of exercise echocardiography and the Duke treadmill score for risk stratification in patients with known or suspected coronary artery disease and normal resting electrocardiogram.

BACKGROUND: Although exercise echocardiography (EE) is not clearly indicated in patients with normal electrocardiogram (ECG) as the first evaluation, there is a lack of data regarding its superiority over the Duke score for prognosis. We investigate whether EE has incremental value over the Duke score for predicting outcome in patients with normal ECG. METHODS: One thousand six hundred forty-seven patients with interpretable ECG referred for EE were followed up for 2.5 +/- 1.4 years. There were 58 hard events (myocardial infarction or cardiovascular death). RESULTS: There were 38 events in 735 patients with abnormal EE versus 20 events in 912 with normal EE (P < .0001). The Duke score, resting wall motion score index, and ischemia were independently associated to events (incremental P value of EE = .03). The Duke score allowed stratification of patients with abnormal EE (P = .001) or ischemia (P = .01) into different risk categories but did not stratify patients without these characteristics. Exercise echocardiography variables stratified patients with the low Duke score (left anterior descending artery territory P = .04, left anterior descending artery ischemia P = .03) and with the intermediate Duke score (abnormal EE P = .005, necrosis P = .0009, ischemia P = .004, resting ejection fraction P < .00001, resting wall motion score index P < .00001, peak ejection fraction P < .00001, peak wall motion score index P < .0001, number of territories P = .002, left anterior descending artery territory P = .001, and left anterior descending artery ischemia P = .002) but did not with the high Duke score. CONCLUSIONS: Exercise echocardiography has incremental value over clinical variables, the Duke score, and resting echocardiography for the prediction of hard cardiovascular events in patients with normal resting ECG.

Coronary Artery Disease↗
PubMed2026

Genomic and integrative based progression biomarker discovery in adult sepsis: toward clinical stratification and precision medicine.

Sepsis is a life-threatening syndrome characterized by a heterogeneous host response to infection that remains a major cause of mortality worldwide. Current clinical scoring systems capture organ dysfunction but fail to reflect the underlying biological diversity, limiting their utility for patient stratification and targeted therapy. This review provides a comprehensive overview of molecular biomarker approaches used to predict sepsis course and prognosis in adult patients, covering genetic, transcriptomic, proteomic, and integrative strategies up to May 2026. Here, we summarize findings from genetic association studies, along with analyses based on polygenic risk scores to aggregate genetic effects, Mendelian randomization, and rare-variant sequencing approaches. We also review transcriptomic and proteomic strategies for endotyping, and diagnostic and prognostic discrimination. Lastly, we discuss how multi-omics integration is emerging as a promising framework to assist in distinguishing causal therapeutic targets from non-causal biomarkers. We also address the challenges that still constrain clinical translation towards precision medicine.

Biomarker↗
PubMed2005

Defining the outcomes of risk stratification studies of ED patients with chest pain: the marginal value of adding revascularization to the composite end point.

OBJECTIVES: Cardiovascular risk stratification studies use various end points, sometimes including revascularization. We assessed whether adding revascularization to a strictly defined composite end point of death, acute myocardial infarction (AMI), and unstable angina (UA) impacts the likelihood of patients attaining the composite end point. METHODS: We conducted a secondary analysis of a prospectively collected data set of emergency department patients who received an electrocardiogram for chest pain. Patients were followed daily; discharged patients had 30-day telephone follow-up. The main outcome was a 30-day composite end point of death, AMI, and UA compared with death, AMI, UA, and revascularization. RESULTS: There were 4492 patients enrolled (mean age, 52 +/- 16 years; men, 41%; African American, 68%). One hundred seventy patients were revascularized (158 had AMI or UA). Overall, the incidence of death/AMI/UA was 20.1% (95% confidence interval, 18.9%-21.2%). With revascularization included, the incidence of the composite end point was 20.3% (95% confidence interval, 19.1%-21.5%). CONCLUSION: When both AMI and UA are strictly defined, there appears to be a limited role for adding revascularization to a composite end point of death, AMI, and UA because most revascularized patients have a diagnosis of AMI or UA.

Acute Disease↗
PubMed2004

Effect of carotid atherosclerosis screening on risk stratification during primary cardiovascular disease prevention.

We investigated the effect that carotid plaque area (CPA) and intima media thickness (IMT) measurements have on risk stratification in 95 patients with intermediate Framingham scores (6% to 19%). The risk status of each patient was adjusted to be low, intermediate, or high based on the results of carotid ultrasound. After carotid testing, 44% (IMT) and 45% (CPA) of the intermediate-risk patients were stratified as low risk, and 22% (IMT) and 40% (CPA) were stratified as high risk. Using the threshold values derived from our laboratory, 28% (IMT) and 45% (CPA) of patients were stratified as low risk, and 35% (IMT) and 27% (CPA) were identified as high risk. These tests adjust the risk strata of >/=63% of patients deemed as having intermediate risk by Framingham scores.

Cardiovascular Diseases↗
PubMed2004

Impact of nephropathy after percutaneous coronary intervention and a method for risk stratification.

Radiocontrast-induced nephropathy (RCIN) after percutaneous coronary intervention (PCI) is associated with grave consequences, but risk stratification of patients has not been well elucidated. This analysis derived a time-insensitive score to predict the risk of RCIN after PCI. A derivation cohort (1993 to 1998) and a validation cohort (1999 to 2002) comprised 20,479 patients who underwent PCI. RCIN after PCI was defined as a >/=1.0 mg/dl increase in serum creatinine. Variables having an independent correlation for RCIN after PCI were used to derive the RCIN risk score from the derivation cohort and were tested in the validation cohort. RCIN occurred in 2% of patients after PCI. Independent variables (with weighted scores) include estimated creatinine clearance <60 ml/min (2), urgent PCI (2), intra-aortic balloon pump use (2), diabetes mellitus (1), congestive heart failure (1), hypertension (1), peripheral vascular disease (1), and contrast volume >260 ml (1). The incidence of RCIN after PCI increased with each unit increase in score (p <0.0001, concordance statistic 0.89). No patient with a score </=1 developed nephropathy, whereas 26% of patients with a score >/=9 developed RCIN after PCI (p <0.0001). Propensity score analysis showed that patients who developed RCIN after PCI, irrespective of the need for hemodialysis, had higher in-hospital rates of major adverse cardiac events (odds ratio 15, 95% confidence interval 11 to 20, p <0.0001). RCIN occurred in 2.0% of PCI patients and was associated with a 15-fold increase in adverse cardiac events. The RCIN risk score was a clinical assessment tool with excellent predictive ability in identifying the larger population at risk for nephropathy in whom preventative strategies are indicated.

Aged↗
PubMed2004

Prognostic stratification of patients with right bundle branch block using dobutamine stress echocardiography.

The presence of a right bundle branch block (RBBB) is associated with increased mortality. We studied the role of dobutamine stress echocardiography for the prognostic stratification of patients with RBBB. The presence of an abnormal dobutamine stress echocardiography was the strongest predictor of cardiac events and provided incremental prognostic information to clinical and stress test data.

Aged↗
PubMed2004

Value of immediate postoperative electrocardiogram to update risk stratification after major noncardiac surgery.

Current consensus guidelines recommend postoperative electrocardiographic surveillance only in patients at relatively high risk of postoperative major cardiac complications, but the usefulness of electrocardiograms after major noncardiac surgery is unknown. We prospectively studied 3,570 patients who underwent major noncardiac procedures and had electrocardiograms performed in the recovery room. Rates of major cardiac complications (acute myocardial infarction, pulmonary edema, ventricular fibrillation or primary cardiac arrest, and complete heart block) were higher in patients who had new postoperative electrocardiographic abnormalities consistent with ischemia (ST-T elevation or depression or T-wave abnormalities compatible with ischemia) compared with those without ischemia (6.7% vs 1.9%, p <0.001). Multivariate analysis, after adjusting for pre- and intraoperative clinical data, indicated that the presence of ischemia on the immediate postoperative electrocardiogram was an independent predictor of major cardiac complications (odds ratio 2.2, 95% confidence interval 1.2 to 3.9, p <0.01). When patients were stratified by a preoperative Revised Cardiac Risk Index, ischemia on the immediate postoperative electrocardiogram identified patients with a higher risk of major cardiac complications in low- and high-risk subsets (odds ratio 4.9, 95% confidence interval 1.6 to 15 in lower risk patients; odds ratio 2.0, 95% confidence interval 1.0 to 3.7 in higher risk patients). We conclude that the immediate postoperative electrocardiogram is a valuable tool to adjust risk stratification, even in patients who have lower risks when undergoing noncardiac surgery.

Aged↗
PubMed2005

Utility of C-reactive protein measurement in risk stratification during primary cardiovascular disease prevention.

High-sensitivity C-reactive protein (hs-CRP) adds prognostic information beyond that provided by the Framingham risk score. The clinical utility of hs-CRP evaluation per guidelines was investigated by determining how it changed the cardiovascular risk stratification of 100 patients deemed at intermediate risk. Screening guidelines defined the cardiovascular risk due to hs-CRP as low (<1.0 mg/L), intermediate (1.0 to 3.0 mg/L), or high (>3.0 mg/L). After hs-CRP evaluation, risk was adjusted in 66% of the patients. Because hs-CRP evaluation significantly altered the cardiovascular risk strata of most intermediate-risk patients, it may therefore be a useful test during primary cardiovascular disease prevention.

Biomarkers↗
PubMed2005

[Risk stratification in congestive heart failure].

Congestive heart failure remains a severe condition. Risk stratification is necessary to assess the prognosis and discuss the potential timing of heart transplant. Numerous criteria have been used, which may be combined to define prognostic scores which, however, are rarely used in routine. A few items, however, may be used to stratify the risk of mortality and sudden death.

Coronary Angiography↗
PubMed2006

[Risk stratification in atrial and ventricular arrhythmias].

Atrial fibrillation, the most frequent arrhythmia, has a growing incidence with increasing age and the most important complication of the disease is thromboembolic events that may be prevented by antivitamin K. They are the most efficient therapeutic class for the prevention of these events but they are associated with an increased haemorrhagic risk leading to a reduced prescription in general practice. Optimisation of the management should be based on an individual evaluation of the thromboembolic and haemorrhagic risks, taking into account age, the presence of an associated heart disease, hypertension, diabetes, history of cerebrovascular event, history of previous haemorrhagic event and the ability to achieve a stable target INR. The challenge in ventricular arrhythmias lies in identifying a high risk of sudden death, mainly related to ventricular fibrillation. In patients with structural heart disease, left ventricular dysfunction is the strongest predictor of sudden death. Non invasive markers such as non sustained ventricular tachycardia, late ventricular potentials, decreased heart rate variability and baroreflex sensitivity, and repolarization altemans are further elements to assess risk. However, most of these markers have a poor positive predictive value and a low specificity. In patients with normal hearts, genetic predisposition may in the future identify high risk patients. The electrophysiologic study with programmed ventricular stimulation remains a costly and invasive method and only has a strong positive predictive value in ischemic cardiomyopathy. More precise algorithms for risk stratification are thus needed that may help the strategy of therapy with prophylactic implantable cardioverter defibrillator in the future.

4-Hydroxycoumarins↗
PubMed2005

LDL cholesterol and global risk stratification in referred hypertensive patients.

BACKGROUND: Global risk status more than BP values per se drive nowadays treatment decisions and increasing emphasis is given to the role of lipid control in hypertension (HT). However, the distribution of circulating low density lipoproteins (LDL) levels as a function of risk profile and lipid-lowering treatment in hypertensive patients is unclear. METHODS: We analysed 1196 patients (677 males, age range: 20-80 years) referred to our Hypertension Unit with treatment history and a complete dataset (systolic blood pressure levels, being on anti-hypertensive treatment or not, total and high density lipoproteins (HDL) cholesterol, smoking status, sex, age) for 10-year absolute coronary heart disease (CHD) risk stratification by National Cholesterol Education Program (NCEP)/ATP III guidelines. LDL cholesterol <25.9 mmol/L (100 mg/dL) was the target for high-risk patients (vascular diseases, diabetes, hypertension with multiple risk factors at CHD risk >20%/10 years). LDL <33.6 mmol/L (130 mg/dL) and 41.4 mmol/L (160 mg/dL) were the thresholds for intermediate (10-20%/10 years) and low (<10%/10 years) CHD risk. RESULTS: At referral, 78% of high-risk patients were above target LDL and, overall, 56% had LDL cholesterol above the desired risk-specific thresholds. Lipid-lowering treatment was prescribed in 19% in whom LDL was actually higher than the untreated group. CONCLUSIONS: LDL cholesterol was out of target in most of a large series of referred high-risk hypertensive patients and LDL levels were largely unsatisfactory even in those undergoing lipid-lowering treatment. The data show the intensive effort still needed to implement global risk-oriented prevention strategies in hypertensive populations.

Adult↗
PubMed2006

Stratification and intra- and inter-specific differences in fatty acid composition of common dolphin (Delphinus sp.) blubber: implications for dietary analysis.

Sixty-five fatty acids were quantified in the blubber of common dolphins (Delphinus delphis, D. capensis) incidentally caught off the coast of southern California. Dolphins were grouped by sex, reproductive status and species, and a blubber sample was collected at a mid-lateral site located caudal to the trailing edge of the dorsal fin. Samples were divided horizontally into inner, middle and outer layers and gradients in fatty acid content (mass percent) were observed across the depth of the blubber. Levels of monounsaturated fatty acids were greatest in the outer layer, whereas levels of saturated and polyunsaturated fatty acids were greatest in the inner layer. Degree of stratification was greatest in sexually mature dolphins. Blubber of sexually immature, but physically mature, male dolphins was also highly stratified, suggesting that this difference may be attributed to differences in diet. Classification and regression tree analysis resulted in the fewest misclassifications when dolphins were grouped by species, possibly indicating that these closely related animals forage on different prey species. Dietary-derived fatty acids were typically selected as splitting criteria in classification and regression tree analyses, suggesting that the observed differences in fatty acid composition between the various groups of dolphins may be attributed to differences in diet.

Animals↗