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PubMed1992

Chronic stable angina pectoris. Risk stratification and treatment.

Workup of stable angina patients begins with careful history taking and evaluation of various risk factors, physical examination, and a resting electrocardiogram (ECG). A noninvasive exercise stress test is valuable for risk stratification. Abnormalities on a resting ECG or equivocal results on a stress test warrant an exercise test combined with thallium scintigraphy, which is more sensitive and specific. Cardiac catheterization is advisable for patients with chest discomfort and multiple risk factors, even if results of thallium testing are negative. Patients with severe or progressive angina or congestive heart failure should also have cardiac catheterization. Nitrates, beta-adrenergic blockers, and calcium channel blockers are cornerstones of medical therapy. Revascularization with coronary artery bypass graft is recommended for patients with left main coronary artery disease, left ventricular dysfunction, or severe proximal three-vessel coronary artery disease. Percutaneous transluminal coronary angioplasty (PTCA) is a good alternative for one- or two-vessel disease. Three-vessel PTCA can be accomplished, but its real role still remains to be established.

Angina Pectoris↗

PubMedDate not supplied

Secular change in height in Austria: an effect of population stratification?

The records of height on some 700,000 18-year-old Austrian males, called for examination as to their fitness for conscription, were analysed. The data covered 14 conscription years (1980-93), representing males born in the years 1962-75. The sample covered over 90% of the total male population of those cohorts in Austria. The data were analysed by birth year to show the secular trend in 18-year-old stature and its rate, which overall amounted to 0.53 cm/decade. Analysis by urban-rural residence showed that both participated in the trend, but that the urban-rural differences were appreciably less than the differences between the types of school the young men had attended. The rate of increase over the 14 years was less within each of the eight subgroups (urban-rural, four school categories). It is argued that the secular trend in height that has occurred is largely attributable to the change in social stratification, as evidenced by the changed proportion of subjects who attended schools of different types.

Adolescent↗

PubMed2006

The safety of a laparoscopic cholecystectomy in acute cholecystitis in high-risk patients older than sixty with stratification based on ASA score.

The purpose of this study was to evaluate the safety of a laparoscopic cholecystectomy (LC) for acute cholecystitis (AC) in patients older than sixty years of age, with stratification based on the ASA (American Society of Anesthesiologists) score. For five years, 137 patients older than sixty, who had undergone a LC for AC, were classified into three groups; ASA 1 (n = 33), ASA 2 (n = 79) and ASA 3 (n = 25). Preoperative percutaneous gallbladder drainage was performed in eight of the 137 cases (5.8%). All except one underwent one-stage management and 19.7% patients underwent emergency surgery within 24 hours of the index admission of AC. The preoperative hospital stay for ASA 3 (8.8 days) was longer than that for ASA 1 (5.6 days). There was a higher proportion of complicated cholecystitis and a longer operating time in ASA 2 (50.6%, 111 min.) and 3 (66.7 %, 114 min.) than in ASA 1 (24.2%, 85 min.) (p<0.05). Morbidity was more frequent in ASA 3 (20.0%) than in ASA 1 (9.1%). However, the open conversion rate, time to diet, and postoperative hospital stay were similar in the three groups (p>0.05). We conclude that a LC for AC may be an effective treatment option in elderly-high risk patients.

Age Factors↗

PubMed2005

Assessment of validity for EuroSCORE risk stratification system.

UNLABELLED: Prognostic scoring helps doctors, patients and their families to weigh the risks and benefits of medical care and clarifies their expectations. OBJECTIVE: We aimed to analyze the risk stratification performance of the EuroSCORE system because of its common use in Lithuania. DESIGN: EuroSCORE performance is assessed in terms of sensitivity, specificity, accuracy and area under the receiver operating characteristic (ROC) curve (AUC). Logistic regression is carried out for modeling categorical data and odds ratio calculations of being a non-survivor case for each EuroSCORE risk group. RESULTS: The study was completed on 1002 patients. Mean score for EuroSCORE was 4.77 +/- 2.8; ROC curve of 0.71; accuracy was 65.5%; 65.4% sensitivity and 67.2% specificity. CONCLUSIONS: EuroSCORE created a moderately predictive area under the ROC curve for our patient population. Probability of non-survival by logistic regression model for each EuroSCORE risk group is statistically significantly higher compared to the lower risk group. Predictions available from prognostic scoring systems could be useful in decision making when there is uncertainty in whether to carry out surgery or not.

Aged↗

PubMedDate not supplied

The biosocial female choice theory of social stratification.

For decades, the study of social stratification has been dominated by environmental theories. Herein a theory is proposed that contains both biological and sociocultural elements. The theory asserts that most human females, like females of many other mammalian species, have evolved mating preferences biased toward males who are competent in provisioning resources. This female bias is hypothesized to have been naturally selected because females with these biases nearly always have had a reproductive edge over females who lack such a bias. One result of this bias is that human females preferentially mate with males who strive to rise in social status. This, in turn, has favored males who attain or at least strive for high social status, and who advertise and even exaggerate whatever status they already have achieved. At the genetic level, the theory postulates that alleles have accumulated on the human genome that promote social status-striving and achievement to varying degrees. To account for why males are more prone toward status-striving than females, the theory contends that one or more genes on the Y-chromosome interact with genes on the remaining human chromosomes to incline males to gravitate toward social hierarchies and to strive for niches that are relatively high in those hierarchies. Both tested and untested hypotheses are derived from the theory and compared to the empirical evidence currently available.

Cultural Evolution↗

PubMed2000

Effects of stratification in the analysis of affected-sib-pair data: benefits and costs.

The benefits and costs of stratification of affected-sib-pair (ASP) data were examined in three situations: (1) when there is no difference in identity-by-descent (IBD) allele sharing between stratified and unstratified ASP data sets; (2) when there is an increase in IBD allele sharing in one of the stratified groups; and (3) when the data are stratified on the basis of IBD allele-sharing status at one locus, and the stratified ASPs are then analyzed for linkage at a second locus. When there is no difference in IBD sharing between strata, a penalty is always paid for stratifying the data. The loss of power to detect linkage in the stratified ASP data sets is the result of multiple testing and the smaller sample size within individual strata. In the case in which etiologic heterogeneity (i.e., severity of phenotype, age at onset) represents genetic heterogeneity, the power to detect linkage can be increased by stratifying the ASP data. This benefit is obtained when there is sufficient IBD allele sharing and sample sizes. Once linkage has been established for a given locus, data can be stratified on the basis of IBD status at this locus and can be tested for linkage at a second locus. When the relative risk is in the vicinity of 1, the power to detect linkage at the second locus is always greater for the unstratified ASP data set. Even for values of the relative risk that diverge sufficiently from 1, with adequate sample sizes and IBD allele sharing, the benefits of stratifying ASP data are minimal.

Age of Onset↗

PubMed2000

Primate DAX1, SRY, and SOX9: evolutionary stratification of sex-determination pathway.

The molecular evolution of DAX1, SRY, and SOX9, genes involved in mammalian sex determination, was examined in six primate species. DAX1 and SRY have been added to the X and Y chromosomes, respectively, during mammalian evolution, whereas SOX9 remains autosomal. We determined the genomic sequences of DAX1, SRY, and SOX9 in all six species, and calculated K(a), the number of nonsynonymous substitutions per nonsynonymous site, and compared this with the K(s), the number of synonymous substitutions per synonymous site. Phylogenetic trees were constructed by means of the DAX1, SRY, and SOX9 coding sequences, and phylogenetic analysis was performed using maximum likelihood. Overall measures of gene and protein similarity were closer for DAX1 and SOX9, but DAX1 exhibited nonsynonymous amino acid substitutions at an accelerated frequency relative to synonymous changes, similar to SRY and significantly higher than SOX9. We conclude that, at the protein level, DAX1 and SRY are under less selective pressure to remain conserved than SOX9, and, therefore, diverge more across species than does SOX9. These results are consistent with evolutionary stratification of the mammalian sex determination pathway, analogous to that for sex chromosomes.

Amino Acid Sequence↗

PubMed2026

Enhanced risk stratification in hypertrophic cardiomyopathy through the integration of extracellular volume fraction on cardiovascular magnetic resonance.

AIMS: This study investigated the incremental prognostic value of cardiovascular magnetic resonance (CMR)-derived extracellular volume fraction (ECV), a marker of diffuse interstitial fibrosis, beyond late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: We analysed 990 consecutive HCM patients (median age 58 years, male 68.3%) who underwent CMR between 2012 and 2024. LGE and global ECV were quantified, and their associations with the primary endpoint of HCM-related events-a composite of sudden cardiac death (SCD) events, heart failure (HF) events, and HCM-related death-were assessed. During a median follow-up of 3.2 years, 64 (6.5%) patients experienced the primary endpoint. While LGE (median 7.1%, IQR 2.3-16.9%) and ECV (median 29.0%, IQR 26.6-32.0%) were moderately correlated (R = 0.604, P < 0.001), both were significantly associated with increased risk of the primary endpoint and individual outcomes of SCD and HF events, and optimal cutoffs were determined as LGE ≥ 27% and ECV ≥ 35%. Patients with ECV ≥ 35% had more symptoms, a more severe phenotype with greater systolic and diastolic dysfunction, and more pathogenic gene variants. Notably, ECV remained a significant predictor of the primary endpoint (adjusted HR 1.08, 95% CI 1.02-1.15, per 1%) after adjustment for key disease variables, including left ventricular ejection fraction and LGE. Elevated ECV effectively identified high-risk individuals even among lower-risk subgroups, including those with low LGE burden. CONCLUSION: Increased ECV is an independent predictor of HCM-related outcomes. ECV may serve as a novel imaging biomarker to refine risk stratification in HCM patients who do not meet traditional LGE-based high-risk criteria.

Humans↗

PubMed1995

Coronary intervention: risk stratification and management of abrupt coronary occlusion.

Balloon angioplasty is associated with an often unpredictable risk of abrupt coronary occlusion, which is the leading cause of in-hospital death and myocardial infarction. Clinical, angiographic and lesion variables predictive of risk of abrupt occlusion are reviewed and a low, medium and high risk profile stratification is developed. Current management of abrupt occlusion is discussed.

Angioplasty, Balloon, Coronary↗

PubMed2005

High-sensitivity C-reactive protein: potential adjunct for risk stratification in patients with stable congestive heart failure.

AIMS: To determine the potential adjunct of high-sensitivity (hs) C-reactive protein for risk stratification in patients with stable congestive heart failure (CHF). METHODS AND RESULTS: We studied 546 consecutive patients clinically stable with an ejection fraction <45% who were referred to our centre for evaluation of left ventricular dysfunction. hs C-reactive protein levels were determined on blood samples obtained on entry into the study. Clinical follow-up (median 972 days) was obtained for 545 patients. Cardiovascular mortality was significantly increased (P=0.001) in patients with hs C-reactive protein >3 mg/L. By multivariable analysis, including clinical, biological, and echocardiographic variables, hs C-reactive protein >3 mg/L was an independent predictor of cardiovascular mortality [HR=1.78 (1.17-2.72); P=0.008]; the strongest predictive parameter in this model was B-type natriuretic peptide (BNP) (P=0.005). When peak VO(2) was included into the model, hs C-reactive protein >3 mg/L remained an independent predictor of cardiovascular mortality [HR=1.55 (1.02-2.38); P=0.04]; the strongest predictive parameter in this model was peak VO(2) (P<0.0001). In patients with ischaemic CHF, cardiovascular mortality was significantly increased in patients with hs C-reactive protein >3 mg/L (P=0.001), whereas in patients with non-ischaemic CHF, hs C-reactive protein >3 mg/L was not associated with cardiovascular mortality (P=0.098). By multivariable analysis, hs C-reactive protein >3 mg/L was an independent predictor of cardiovascular mortality in ischaemic patients [HR=2.16 (1.23-3.78)] but not in non-ischaemic patients [HR=1.05 (0.52-2.11)]. CONCLUSION: Cardiovascular mortality is increased in CHF patients with hs C-reactive protein >3 mg/L. The impact of hs C-reactive protein is independent of usual prognostic parameters, in particular BNP and peak VO(2). The interest of hs C-reactive protein determination appears to be especially marked in patients with ischaemic cardiomyopathy.

C-Reactive Protein↗

PubMed2006

Electrocardiographic risk stratification in families with congenital long QT syndrome.

AIMS: The QT interval in the surface ECG is one of the most often used risk stratifiers in families with congenital long QT syndrome (LQTS). The best ECG lead for clinical management of LQTS families remains unclear. METHODS AND RESULTS: The predictive power of the QTc interval in all ECG leads was studied in 200 consecutive genotyped LQTS family members to identify mutation carriers (n = 103; age: 35+/-19 years) and high-risk LQTS patients (n = 16 with survived sudden cardiac arrest) using receiver operating curve (ROC) analysis (ROC = area under curve). Additionally, the risk for events (syncope and sudden cardiac arrest) was calculated for QTc decile in all individuals. The predictive power was highest in lead II and lead V5 for identifying carriers in LQTS families. These ECG leads were optimal for risk stratification (ROC range 0.83-0.87). In these leads, positive predictive value (PPV) and negative predictive value (NPV) were highest for suggested QTc cut-offs (440 and 500 ms) for identification of LQTS mutation carriers and high-risk patients (PPV between 78-81 and 73-80%, respectively). The risk for events in QTc deciles increased exponentially from 10 to 80% and was 40% for QTc > 500 ms. CONCLUSION: On the basis of these data, QTc is the best diagnostic and prognostic ECG parameter in LQTS families. A single measurement should be obtained in lead II if measurable and then in left precordial leads (preferably V5) as a second choice.

Adult↗

PubMed1992

Educational attainment, occupational history, and stratification: determinants of later-life economic outcomes.

Determinants of economic well-being among men 25-44, 45-64, and 65+ were examined using data from the 1984 panel of the Survey of Income and Program Participation. A path analysis explored race, education, and occupational history effects on income adjusted for annuitized assets, household composition, and underreporting of unearned income. Direct and total education effects were undiminished among elderly persons, whose income derived mainly from benefits and assets, as compared with the nonelderly subjects whose income was dominated by earnings; education explained more of the variance in adjusted income for the elderly group than for the nonelderly. While Social Security income exerts an equalizing effect across educational attainment groups, private pensions and other important retirement income sources were highly education-dependent, producing a high overall degree of stratification on early-established socioeconomic characteristics.

Adult↗

PubMed1998

Patterns of care study of radiation therapy for esophageal cancer in Japan: influence of the stratification of institution on the process.

BACKGROUND: To improve the quality of radiation therapy in Japan, Patterns of Care Study (PCS), a widely known QA program in the USA, was introduced in Japan. The feasibility was tested by collecting nationwide data by extramural audit for esophageal cancer. METHODS: From July 1996 through February 1997, PCS audits were performed for 29 institutions. Based on the facility survey by Tsunemoto, 13 institutes were classified as A1 (university hospital/cancer center treating > 300 patients/year), 10 as B1 (other institutes > 120 patients/year) and six as B2 (other institutes < 120 patients/year). Medical charts for 455 patients with thoracic esophageal cancer between 1992 and 1994 were reviewed based on the data format of PCS in the USA. RESULTS: Concerning external beam equipment, linear accelerators of > or = 10 MV were used for 73% of patients in A1, whereas in B1-2, 60Co machines were still used for 13% of patients (P < 0.0001). The median number of full-time equivalent (FTE) radiation oncologists was 2.7 in A1, 0.65 in B1 and 0.2 in B2. Forty-five percent of patients had received surgery in A1 and 34% in B1-2 (P = 0.0068). In the non-surgery group, a higher radiation dose of > 60 Gy was delivered in A1 than in B1-2 (P = 0.0008). Chemotherapy was administered to 51% of the patients in A1 and to 30% in B1-2 (P < 0.0001). Brachytherapy was utilized for 17% in A1 and only for 5% in B1-2 (P = 0.0001). CONCLUSION: Institutional stratification, including equipment and personnel, significantly affected the patterns of care for esophageal cancer. Therefore, to improve the quality of radiation therapy nationwide, improvement of equipment and supply of FTE personnel is extremely important. PCS was found to have great potential for the practical evaluation of how much will be required in Japan.

Adult↗

PubMed1998

Patterns of care study of radiation therapy for cervix cancer in Japan: the influence of the stratification of institution on the process.

BACKGROUND: To improve the quality of radiation oncology in Japan, Patterns of Care Study (PCS), a widely known quality assurance (QA) program in the USA, was introduced. The feasibility was tested by collecting nationwide data by extramural audit for cervix cancer. METHODS: From July 1996 through February 1997, PCS audits were performed for 29 institutions nationwide. On the basis of the facility survey by Tsunemoto, 13 institutions were classified as A1 (university hospital/cancer center), 10 as B1 (other institutions treating >120 patients/year) and six as B2 (other institutions treating <120 patients/year). Medical charts for the patients treated for cervix cancer between 1992 and 1994 were reviewed based on the data format of the US PCS. The total number of patients surveyed was 432. RESULTS: Simulation was used for >90% of the patients in both A1 and B1-2 institutions. However, in B1-2, planning for 5% of the patients was performed with only a clinical set-up (p = 0.0287). A daily fraction with a size of 200 cGy was given to >65% of patients in A1 and to <47% in B1-2. On the other hand, >50% of those in B1-2 were treated with daily fractions of 180 cGy and less compared with 25% in A1 institutions (p < 0.0001). Brachytherapy was utilized more frequently for patients in Stages II (p = 0.0365), III (p = 0.0015) and IV (p = 0.0483) in A1 than in B1-2. As for external beam equipment, linear accelerators with 10 MV or more were used for 83% of the patients in A1. However, in B1-2 institutions, machines with lower energy were used for 38% of the patients (p < 0.0001). The median number of full-time-equivalent (FTE) radiation oncologists was 2.7 in A1, 0.65 in B1 and 0.2 in B2. CONCLUSIONS: Institutional stratification, including equipment and personnel, was found to affect significantly the patterns of care for cervix cancer. Therefore, to improve the quality of radiation therapy nationwide, improvements in equipment and in supply of FTE personnel are extremely important. PCS was found to have great potential for a practical evaluation of how much improvement will be required in Japan.

Adult↗

PubMed2026

Genetic risk stratification of common diseases in breast cancer survivors: a population-based cohort study.

IMPORTANCE: Patients diagnosed with breast cancer (BCa) are at increased risk of multiple common diseases; however, the spectrum of these diseases and the contribution of inherited genetic susceptibility remain incompletely characterized. METHODS: We evaluated 15 common diseases and tested their associations with BCa exposure and disease-specific polygenic risk scores (PRS) in the UK Biobank (UKB; N = 254,736). Analyses were performed using cause-specific Cox proportional hazards models within a full-cohort framework, with time-updated BCa status, delayed entry at study recruitment, and age as the underlying time scale. RESULTS: After recruitment, incident BCa was diagnosed in 11,386 women (4.47%), including 2,742 (24.08%) with metastatic BCa. Patients with BCa had an increased risk of nine diseases spanning cardiovascular, metabolic, and neuropsychiatric domains (P<0.003, Bonferroni-corrected). Elevated risks were generally observed among patients with both early staged and advanced BCa. Inherited susceptibility further stratified disease risk, with the highest risks observed among patients with BCa with elevated disease-specific PRS. For example, compared with women without BCa, the hazard ratio (HR; 95% CI) for osteoporosis was 2.33 (2.15-2.52) among women with any BCa, 2.38 (2.18-2.59) among those with non-metastatic BCa, and 2.12 (1.78-2.54) among those with metastatic BCa; the HR was 4.48 (3.99-5.02) among patients with BCa in the highest quartile of osteoporosis-specific PRS (all P<0.001). In contrast, BCa was not significantly associated with risk of coronary artery disease. CONCLUSION: BCa and inherited genetic susceptibility jointly contribute to increased risk of multiple common diseases, supporting the integration of genetic risk stratification into survivorship care.

Complications↗

PubMed2026

Mutational signature stratification of recurrent gliomas reveals distinct patterns of genomic traits.

BACKGROUND: Although temozolomide (TMZ) is widely used for glioma treatment, its therapeutic benefit is limited by acquired resistance and recurrence, facilitated by intratumor heterogeneity. Mutational signatures (MSs) inform tumor evolution and reveal alterations associated with treatment response. METHODS: We performed molecular analyses of 96 glioma recurrences with sufficient private single-nucleotide variants relative to their matched primary tumors, stratified by their dominant MS. RESULTS: Four groups were identified: MS11/TMZ-related (n = 38), MS1/5/aging-related (n = 32), MS6/15/21/26/microsatellite instability (MSI)-related (n = 13), and other MS-related recurrences (n = 13). MS11/TMZ-related recurrences showed higher acquired mutational counts than the other groups (1338 vs 59 (MS1/5/aging) vs 57 (MS6/15/21/26/MSI) vs 57 (other MSs); P < .01). Mutations in SYNE2, SZT2, and FBN3 were restricted to recurrences with dominant or second-dominant MS11/TMZ-related signature (n = 41), and 85% (35/41) harbored mutations in these genes. In MS11/TMZ-related recurrences with RNA sequencing data (n = 17), mRNA co-expression analyses identified SYNE2-ATAD5 and SZT2-MAPKBP1 associations. Among MS11/TMZ-related recurrences, MS23 was frequent (44%, 18/41) and associated with higher acquired mutational counts (2089 vs 1188; P = .018) and more IDH-wildtype tumors (67% vs 30%; P = .037). MAPKBP1 mutations were enriched in MS23-positive recurrences (56% (10/18) vs 0% (0/23); P < .001). MS1/5/aging-related recurrences showed more frequent acquired chromosome 16q losses (22% vs 8% (TMZ) vs 0% (MSI) vs 0% (other); P < .05), which were associated with an increased fraction of genome altered relative to 16q-diploid cases (15% vs 7%; P = .01). CONCLUSIONS: These findings show that MS-based stratification of recurrences refines molecular characterization after therapy and nominates candidate biomarkers and pathways for functional studies of treatment-associated glioma evolution.

mutational signatures↗

PubMed1976

Stratification by a multivariate confounder score.

The complexity and inefficiency of multiple cross-classification as a means of controlling confounding in etiologic research may be avoided upon summarizing the pattern of confounding factors for each subject in terms of a multivariate score. The control of confounding may be based on stratification by the score, with stratum-specific contingency tables obtained and analyzed in the usual manner.

Biometry↗

PubMed1997

Non-invasive risk stratification within 48 h of hospital admission in patients with unstable coronary disease.

AIMS: In this study we evaluated the prognostic value of three methods of early risk estimation in patients with unstable coronary disease. METHODS AND RESULTS: The methods evaluated were: clinical risk estimation at hospital admission, continuous ST analysis with computerized vectorcardiography for 24 h and serial measurements of creatinine kinase-MB for 48 h. Twenty-seven (14%) of the 195 patients died or had a non-fatal infarction within one year. Clinical risk evaluation correctly identified a subgroup of patients with low risk but did not otherwise predict outcome. Fifty-six (29%) patients had ST vector magnitude episodes on vectorcardiography, 70 (38%) had three or more episodes of ST change vector magnitude and 74 (38%) had a peak creatinine kinase-MB value of 6 microgram.l-1 or more. The even rate for patients with ST vector magnitude episodes (23%) was significantly higher than for those without (10%; P < 0.05). For patients with and without three or more episodes of ST change vector magnitude the event rate was 23% and 9% respectively (P < 0.05) and for patients with and without creatinine kinase-MB > or = 6 microgram.l-1 the event rate was 23% and 8% respectively (P < 0.01). The positive predictive value of having none, either one or both of the ST or creatinine kinase-MB markers positive was incremental. CONCLUSION: Continuous vectorcardiographic monitoring of ischaemia in combination with serial creatinine kinase-MB measurement considerably improves risk stratification in unstable coronary disease.

Adult↗