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At least 667 records · Page 37Linked to original sources
PubMed2004

Psychosocial correlates of substance use among adolescents in Mersin, Turkey.

The objective of this study was to determine the effects of psychosocial factors such as peer group, family and academic self-perception on smoking, alcohol and substance use by adolescents living in Mersin, Turkey. The study included a total of 3282 students from the sixth and tenth grades and college. The number of participating students required from each school was obtained through stratification, and by weighing the enrolled student population in each subgroup. The final sample was derived using a simple random sampling technique. A 45-item self-administered questionnaire was used. The questionnaire included questions about socio-demographic characteristics and lifetime and current (i.e. within the past month) use of cigarettes, alcohol, cannabis, inhalants and other illicit drugs (heroin, cocaine, sedative-hypnotic drugs, etc.). This study found that: (1) higher socio-economic status of the family increased the likelihood of smoking and alcohol use in adolescents; (2) the prevalence of alcohol use was higher in adolescents whose mothers had a higher educational level and whose mothers and fathers drank alcohol; (3) there was a significant association between substance use and having a peer who used a substance; and (4) the prevalence of smoking was significantly higher in students who perceived their academic performance to be poor. Understanding the role and importance of psychosocial factors associated with smoking, alcohol and substance use will be crucial to develop preventive measures for adolescents.

Adolescent↗
PubMed2005

Langerhans cell histiocytosis: current insights in a molecular age with emphasis on clinical oral and maxillofacial pathology practice.

Langerhans cell histiocytosis (LCH) commonly involves the oral and maxillofacial region, and comes to the attention of dental practitioners when a patient presents with orofacial pain and a bony or soft tissue lesion. This is a relatively rare entity, which has made it difficult to investigate the clinical, biologic, and molecular aspects of the disease. Treatment protocols are not well defined, particularly in adults. During the past decade, the Histiocyte Society has formulated various LCH categories, based on risk stratification, and treatment protocols for the pediatric population. Adult trials are currently available through the Histiocyte Society. Although there has been considerable controversy, the neoplastic nature of LCH has been established by demonstrating clonality. LCH symptoms and the development and persistence of LCH lesions have been ascribed to a "chemokine/cytokine storm" due to autocrine and paracrine mechanisms. Discovery of biologic, cytogenetic, and molecular abnormalities in LCH have already affected treatment by providing novel therapeutic targets.

Adult↗
PubMed1998

Polymorphisms in the human CC chemokine receptor-3 gene.

CC chemokine receptor (CCR)-3 is a seven-transmembrane-spanning G-protein-coupled receptor (GPCR) that is involved in the recruitment of inflammatory cells in allergic responses and acts as a co-receptor for entry of HIV into cells. Selected polymorphisms in GPCRs have been shown to have dramatic effects on the manifestation and/or susceptibility to a variety of diseases. In this report, we tested whether the human CCR-3 gene locus is genetically polymorphic. Using single-stranded conformational polymorphism analysis of genomic DNA, the CCR-3 gene is shown to contain four nucleotide polymorphisms with allele frequencies ranging from 0.005 to 0.13. Two polymorphisms encode for an amino acid change. One of these polymorphisms encodes for a non-conservative change of arginine to glutamine at position 275 of the third extracellular loop. Stratification of the DNA samples into a population with asthma suggested no change in this allele's frequency. Another polymorphism encodes for a leucine to proline substitution in the intracellular cytoplasmic tail of CCR-3. The most frequent polymorphism, T51C, occurs in 26% of individuals and encodes for a silent substitution. Thus, CCR-3 contains several genetic variations which may have consequences in disease processes that involve this receptor.

Adolescent↗
PubMed1997

Markers of risk after acute myocardial infarction. A comparison of clinical variables, ambulatory and exercise electrocardiography, echocardiography, and stress echocardiography.

BACKGROUND: Short-term mortality after myocardial infarction has decreased continuously among members of selected populations. Nonetheless, the long-term prognosis among members of unselected populations remains bad. Further research in risk stratification is therefore needed. In the present study we tested the additive value of clinical variables, echocadiography, ambulatory electrocardiography, exercise testing, and stress echocardiography in assessing the long-term prognosis after acute myocardial infarction. METHODS: Two-dimensional echocardiography and ambulatory electrocardiography (analysis of ST-segment changes and of heart rate variability) were performed for 74 patients aged < 75 years who had had an acute myocardial infarction. Before their discharge from hospital, 70 patients were subjected to a combined exercise test and stress echocardiography. The time of follow-up was > or = 3 years. RESULTS: During follow-up 18 patients died, and 38 suffered cardiac events defined as death, nonfatal reinfarction and the need for revascularization. We first tested 31 covariates in a univariate regression analysis. A subsequent multivariate analysis was performed in two stages. During the first of these, clinical variables (a history of systemic hypertension, infarct localization, and diabetes mellitus) and variables derived from noninvasive tests (new-onset wall-motion abnormality during stress echocardiography, ST-segment depression and heart-rate variability during ambulatory electrocardiography, the ejection fraction by echocardiography at rest, and the double product during exercise tests) predicted mortality. After the second stage, however, the only remaining independent predictors of mortality were the presence of a new-onset wall-motion abnormality (P < 0.0001, relative risk 13.5, 95% confidence interval 3.6-51.3), ST-segment depression during ambulatory electrocardiography (P = 0.003, relative risk 5.0, 95% confidence interval 1.7-15.7) and a decreased heart rate variability (P = 0.007). CONCLUSIONS: The only variables that were of independent value in assessing the long-term mortality were those expressing residual myocardial ischemia and the cardiovascular sympatho-vagal balance. It is, therefore, recommended that one should monitor these variables for patients recovering from an acute myocardial infarction.

Aged↗
PubMed2005

Prevalance of proteinuria in Mexico: a conjunctive consolidation approach with other cardiovascular risk factors: the Mexican Health Survey 2000.

BACKGROUND: A number of cross-sectional or serial studies have demonstrated the clinical impact of microproteinuria and macroproteinuria by identifying individuals at risk of both end-stage renal disease and major cardiovascular events. This study focused on the prevalence of proteinuria in Mexico and its relationship with other cardiovascular risk factors such as hypertension, type 2 diabetes mellitus, body mass index, smoking, age, and gender. METHODS: The prevalence of proteinuria in Mexico was obtained from the probabilistic cross-sectional national health survey performed in the year 2000. The proportion of urine dipstick samples that tested positive for protein (defined as > or =1+) in adults from 20 to 69 years of age was determined. The analysis was performed using both algebraic and multicategorical models. Potential interactions between proteinuria and other major cardiovascular risk factors were investigated. RESULTS: A total of 46,523 adult survey participants were included in the analysis. In the general population, 9.2% had proteinuria. By univariate, multivariate, and multicategorical analysis, hypertension, diabetes, obesity, and age were strongly associated with the prevalence of proteinuria (P < 0.001). However, in Mexico, the specific distribution of age groups demonstrated that the absolute number of patients without hypertension that had proteinuria is not irrelevant. To identify 1 case of proteinuria, one would need to screen 3 persons with diabetes mellitus, 5 patients with hypertension without diabetes, or 6 persons over the age of 55 years. When proteinuria is present, the probability of having a noncommunicable chronic disease or other major cardiovascular risk factor is more than 85%. CONCLUSION: Proteinuria is prevalent. When considered together, dipstick-positive proteinuria, blood pressure level, body mass index > or =30 m(2)/kg, and abnormal fasting blood glucose measured on a single occasion identifies different segments of the population. Studies such as this may be a suitable initial clinical approach to general population screening for renal and cardiovascular risk stratification.

Adult↗
PubMed2005

[The application of the SCORE charts to advanced age males triple the number of high-risk subjects compared to the Framingham function].

BACKGROUND AND OBJECTIVE: The Framingham function, recommended by the National Cholesterol Education Program in its document Adult Treatment Panel III (ATP III), and the risk charts of the Systematic Coronary Risk Evaluation (SCORE) program are the most used functions for risk stratification. In both, intensive hygienic and therapeutic measures are recommended for high risk individuals. The objective of the present study was to compare the risk stratification obtained with both functions in a population of subjects older than 60 years. SUBJECTS AND METHOD: 1001 non-diabetic subjects between 60 and 79 years old (mean: 69 years, 67% female) with no evidence of cardiovascular disease were included in the study. Participants were classified as low, moderate or high risk by ATP-III (< 10%, 10-20% y > 20% of risk at 10 years, respectively) and by SCORE (< 3%, 3-4% y > or = 5% of risk at 10 years respectively). RESULTS: 11.7% of the population was classified as high risk by Framingham and 17.6% by SCORE. Only 5% of the females were classified as high risk with either function. In males, 16.7% and a 44.4% were classified as high risk by Framingham and SCORE respectively. The results did not differ by age group. A 39% of males and a 20% of females were candidates to hypolipidemic treatment as recommended by SCORE guidelines. CONCLUSIONS: Compared to Framingham function, the application of SCORE charts to spanish males over 60 years triplicate the number of high risk individuals and candidates to intensive risk factor treatment.

Aged↗
PubMed2004

Combined echocardiographic left ventricular hypertrophy and electrocardiographic ST depression improve prediction of mortality in American Indians: the Strong Heart Study.

Echocardiographic left ventricular hypertrophy (Echo-LVH) and ST segment depression (STD) on the ECG have each been demonstrated to predict cardiovascular (CV) and all-cause (AC) mortality. However, the prognostic value of combining Echo-LVH and ECG-STD has not been examined. ECGs and echocardiograms were examined in 2193 American Indian participants in the second Strong Heart Study examination. STD was measured by computer and was considered abnormal if > or =50 microV. Echo-LVH was defined by indexed LV mass >116 g/m2 in men and >104 g/m2 in women. After a mean follow-up of 3.1+/-0.7 years, there were 57 CV and 169 AC deaths. In univariate Cox analyses, Echo-LVH (chi2=54.2 and chi2=68.5) and ECG-STD (chi2=35.9 and chi2=46.3, all P<0.001) predicted CV and AC mortality, respectively. The combination of Echo-LVH and ECG-STD improved risk stratification compared with either alone for both CV death (chi2=74.4, P<0.001) and AC death (chi2=102.0, P<0.001), with presence of both ECG-STD and Echo-LVH associated with the greatest risks. After adjustment for age, sex, and relevant risk factors, combined Echo-LVH and ECG-STD remained predictive of CV mortality (chi2=19.7, P<0.001) and AC mortality (chi2=24.9, P<0.001), with the presence of both Echo-LVH and ECG-STD associated with a 6.3-fold increased risk of CV death (95% CI: 2.8 to 14.2) and a 4.6-fold increased risk of AC mortality (95% CI: 2.5 to 8.5). ECG-STD and Echo-LVH additively increase the risk of both CV mortality and AC mortality. These findings support the value of combining Echo-LVH and ECG-STD to improve risk stratification. These findings require verification in other populations.

Aged↗
PubMed2004

Partitioning of nongaussian-distributed biochemical reference data into subgroups.

BACKGROUND: The aim of this study was to develop new methods for partitioning biochemical reference data, covering in particular nongaussian distributions. METHODS: We recently proposed partitioning criteria for gaussian distributions. These criteria relate to proportions of the subgroups outside each of the reference limits of the combined distribution (proportion criteria) and to distances between the subgroup distributions as correlates of these proportions (distance criteria). However, distance criteria do not seem to be ideal for nongaussian distributions because a generally valid relationship between proportions and distances cannot be established for these. RESULTS: Proportion criteria appear preferable to distance criteria for two additional reasons: (a) The prevalences of the subgroup populations may have a considerable effect on stratification, but these are hard to account for by using distance criteria. Two methods to handle prevalences are described, the root method and the multiplication method. (b) Tied reference values, another complication of the partitioning problem, could also be hard to take care of using distance criteria. Some solutions to the problems caused by tied reference values are suggested. CONCLUSIONS: Partitioning of biochemical reference data should preferably be based on proportion criteria; this is particularly true for nongaussian distributions. Both of the described complications of the partitioning problem, the prevalences of the subgroups and tied reference values, are hard to deal with using distance criteria, but the proposed methods make it possible to account for them when proportion criteria are applied.

Clinical Laboratory Techniques↗
PubMed2001

C-reactive protein and coronary heart disease: diagnostic and therapeutic implications for primary prevention.

Coronary heart disease (CHD) is the leading cause of death in the industrialized world. Recent laboratory and clinical studies have shown that inflammation plays a pivotal role in the inception, progression, and destabilization of atheromas. The acute-phase reactant C-reactive protein (CRP) has been shown to reflect systemic and, perhaps, vascular inflammation and to predict future cardiovascular events in asymptomatic individuals. The relative risk associated with CRP is independent of other cardiovascular disease risk factors. High-sensitivity assays (hs-CRP) are needed for the measurement of CRP concentration for the purpose of predicting the risk of future coronary events. Available assays must be standardized because patients' results will be interpreted using population-based cutpoints. An algorithm for risk stratification incorporating hs-CRP and total cholesterol to high-density lipoprotein cholesterol ratio has been developed. Statin class drugs and aspirin appear to modulate CHD risk in those with increased hs-CRP concentration. Several prospective studies are now underway to specifically develop novel clinical utilities and therapeutic strategies for hs-CRP.

C-Reactive Protein↗
PubMed2006

Clinico-pathologic features of chronic myeloid leukemia and risk stratification according to Sokal score.

OBJECTIVE: To compile the clinical and haematological parameters of chronic myeloid leukemia (CML) and risk stratification according to Sokal score in our population. DESIGN: A descriptive analysis. PLACE AND DURATION OF STUDY: The Aga Khan University Hospital, during the period from August 1997 to August 2005. SUBJECTS AND METHODS: All patients with diagnosis of chronic myeloid leukemia treated as outpatient in haematology clinic, or admitted in haem-oncology wards in The Aga Khan University Hospital were included. Records were retrospectively analyzed for clinicopathologic features. Risk groups were assigned as per Sokal scoring. RESULTS: During the 8 years study period, 245 patients with chronic myeloid leukemia were analyzed, the median age of presentation was 35 years (range 11-73); with male to female ratio 1.69:1. At the time of diagnosis, 178 patients (72.6%), 48 (19.7%) and 17 (7.8%) of patients were in chronic, accelerated and blast phase of the disease respectively. Abdominal fullness was the frequent clinical presentation followed by fever. Laboratory parameters revealed mean hemoglobin 10.0 g/dl (range 4.6-15), mean total leukocyte count 168 x 10(9)/L (35-959) and mean platelets 408 x 10(9)/L (range 30-2335). The mean size of spleen at the time of presentation was 9.2 cm below the left subcostal margin. A large number of patients (46.2%) were in high risk group according to Sokal score i.e. > 1.2. CONCLUSION: CML occurred more commonly at younger age in this series. Most of these patients were in high risk group according to Sokal score.

Adolescent↗
PubMed2004

Immunohistochemical aid at risk stratification of melanocytic neoplasms.

There is increasing awareness of the population about the risk of cutaneous melanoma. In recent years, some improvement was gained in the early recognition of clinical warning signs using dermoscopy. As a result, the number of puzzling cases exhibiting limited classical clues for malignancy are submitted to the dermatopathologist. Thus, the risk of microscopic uncertainty or misdiagnosis may be increasing. The aim of the study was to assess retrospectively the contribution of immunohistochemistry in establishing the histological diagnosis of 520 melanocytic neoplasms. According to the disease evolution and the histological presentation, 6 profiles of phenotypical expressions were distinguished.

Antibodies, Monoclonal↗
PubMed2003

[Barrett's esophagus: new developments in endoscopic surveillance].

The current surveillance strategies for patients with a Barrett's oesophagus are hampered by the poor endoscopic visibility of early neoplastic lesions, the sampling error of random biopsies, the subjectivity of the histological evaluation, and the low incidence of carcinoma. New endoscopic techniques are available for a more reliable evaluation of a Barrett's oesophagus: high-resolution endoscopy, chromoendoscopy, fluorescence endoscopy and optical coherence tomography. The use of molecular markers will probably lead to a better risk stratification of patients. Detection of aneuploid cell populations and assessment of an increase of the number of cells in the S- and G2-phase are possible with DNA flow cytometry; flow cytometric abnormalities may be a more reliable predictor of carcinoma than histological assessment. A combined approach with the new endoscopic techniques and molecular markers may lead to a more efficient and cost-effective surveillance programme.

Barrett Esophagus↗
PubMedDate not supplied

[The importance of primary health care of elderly people in Zagreb].

A survey was conducted on a representative sample of 2400 users of primary health care in the city of Zagreb. A sampling procedure was used with stratification by age, (1) the younger age population (18 to 64 years) including early maturity, middle age and late maturity; (2) elderly (65 to 74 years); and (3) the extremely elderly population (74 to 94 years). The analysis of the data collected showed that the number of patients suffering from 2-3 diseases in the 18-64 year age group was 44.36%, 52.23% in the 65-74 age group, and 47.03% in the 74-94 age group. In the course of treatment, general practitioner referred 81.88% of those in the 18-64 year age group, only 11.03% of those aged 65-74 and 7.09% of those in the extremely elderly population to various specialists. Apart from the fact that younger population more often suffers from acute diseases and unclear conditions leading to higher demand for treatment by specialists, one has to accept that elderly people entrust their health protection mainly to general practitioners, and here is a great chance for primary health care to develop, through its institutions, programmes aiming at the health promotion and health protection.

Aged↗
PubMed2026

Age- and sex-adjusted genomic differences between Korean and Beat AML cohorts.

Genomic profiling plays a central role in risk stratification and therapeutic decision-making in acute myeloid leukemia (AML), yet the clinical implications of population-specific genomic architectures remain incompletely defined. We conducted a prospective, multicenter study of 603 adults with newly diagnosed AML in Korea, integrating targeted sequencing of 83 recurrently mutated genes with comprehensive clinical annotation across treatment intensities, including allogeneic hematopoietic stem cell transplantation (allo-HSCT). For contextual comparison, genomic profiles were evaluated against the Beat AML cohort. The overall genomic landscape was broadly conserved, supporting shared core disease biology across populations. However, RUNX1::RUNX1T1, CEBPA, GATA2, KIT, and DDX41 mutations were more frequent in the Korean cohort, whereas FLT3 and NPM1 mutations were less common. These differences translated into a distinct distribution of European LeukemiaNet (ELN) 2022 risk categories, with implications for therapeutic stratification. Notably, most DDX41 alterations were germline (3.2%), highlighting the need for systematic germline evaluation with implications for genetic counseling and donor selection. Although unadjusted overall survival appeared longer in the Korean cohort, this difference was not significant after adjustment for key clinical variables. These findings indicate that population-specific genomic distributions reshape the clinical application of risk stratification and support population-aware precision medicine strategies in AML.

Journal Article↗
PubMed2005

C-reactive protein in the prediction of cardiovascular and overall mortality in middle-aged men: a population-based cohort study.

AIMS: Cut-offs for C-reactive protein concentrations have been recommended for risk stratification, but little is known about how these cut-offs predict cardiovascular risk in population-based cohorts. We therefore assessed the association of C-reactive protein levels with cardiovascular mortality in a population-based cohort of 2321 middle-aged men stratified by the presence of cardiovascular disease (CVD) at baseline. METHODS AND RESULTS: C-reactive protein concentrations were categorized according to current recommendations (1 and 3 mg/L). During the 15 year follow-up, 77 men without CVD and 121 men with CVD at baseline died of CVD. In men without CVD at baseline (n=1476), age-adjusted cardiovascular mortality was 4.1-fold higher (95% CI 2.1-8.2) for C-reactive protein levels between 3.0 and 9.9 mg/L at baseline than for C-reactive protein levels <1.0 mg/L. In men with CVD at baseline (n=845), the corresponding age-adjusted cardiovascular mortality was 3.3-fold higher (95% CI 2.0-5.3). Adjustment for conventional CVD risk factors attenuated the risk somewhat. Further adjustment for dietary and lifestyle factors and factors related to insulin resistance did not affect the association. Classification of C-reactive protein by tertiles gave qualitatively similar results, but identified twice as many men at high risk. C-reactive protein levels also predicted overall mortality. CONCLUSION: Currently, recommended cut-offs for C-reactive protein levels identify men at risk for cardiovascular and overall death independently of conventional and other risk factors in a population-based sample of middle-aged men with and without CVD at baseline. Lower cut-offs may better identify men at high risk for cardiovascular death, but improvement of current recommendations will require standardization of C-reactive protein assays.

Adult↗
PubMed2002

Spectrum bias or spectrum effect? Subgroup variation in diagnostic test evaluation.

Diagnostic tests must be evaluated in a clinically relevant population. However, test performance often varies across population subgroups. Spectrum bias, a term commonly used to describe this heterogeneity, is typically thought to occur when diagnostic test performance varies across patient subgroups and a study of that test's performance does not adequately represent all subgroups. Yet subgroup variation is not a bias if appropriate analyses are conducted. Failure to recognize and address heterogeneity will lead to estimates of test performance that are not generalizable to the relevant clinical populations. Heterogeneity can be addressed with relatively simple stratification procedures, limited primarily by the sample size and the precision of the estimates. This paper proposes the use of the term spectrum effect, rather than spectrum bias, and outlines strategies for using stratified sensitivity and specificity estimates, likelihood ratios, and receiver-operating characteristic curves. Investigators of diagnostic tests should consider the potential for spectrum effect seriously and should address heterogeneity in their analyses. Furthermore, clinicians should consider study samples carefully to determine whether results are generalizable to their specific patient population.

Adult↗
PubMed2000

Building bridges between populations and samples in epidemiological studies.

The increased use of rigorous population-sampling methods and the analysis of data from those samples in cross-sectional surveys, case-control studies, longitudinal-cohort investigations, and other epidemiological research efforts have raised important statistical issues for health analysts. We describe the origin, implications, and some plausible resolutions for several of these issues. Some of the main issues we consider include (a) establishing whom the sample represents; (b) using sample weights; (c) understanding the role of other important features, such as the use of sampling stratification and the selection of clustered groups of population members; and (d) finding ways to analyze study data with key sampling features in mind. Ultimately, resolution of all of these issues requires that analysts clearly define a reference population and then understand the role of design features in relating sample results to that population.

Bias↗
PubMed2005

Venous thromboembolism prophylaxis in medically ill patients and the development of strategies to improve prophylaxis rates.

Venous thromboembolism (VTE) is common but often unrecognized in medically ill patients. Over the past 5 years, three large-scale placebo-controlled trials enrolling a total of 5500 medically ill patients have highlighted the risk of VTE in this group. These trials have helped to define a specific at-risk patient profile, including those admitted to the hospital with severe congestive heart failure, respiratory illness, acute infection, and inflammatory bowel disease. We performed a retrospective review of patients admitted to the medical service at our tertiary care center to define how common the at-risk medical patient is and to evaluate and improve prophylaxis rates in this patient group. The study was conducted in two phases. Based on admission characteristics, patients were stratified into high-risk or low-risk groups for the development of VTE. During the pre-intervention phase, 75% of patients admitted to the medical service were characterized as increased risk for VTE, yet only 43% of these high-risk patients received prophylaxis of any sort. After interventions designed to increase awareness of VTE, we conducted a second review period. In this post-intervention phase, where 79% of patients were at risk for VTE, prophylaxis rates improved to 72%. Based on these results, we conclude that the majority of patients admitted to the medical service at our tertiary care center constitute a high-risk population that warrants consideration for VTE prophylaxis. Implementation of strategies to improve prophylaxis rates, including educational sessions and risk stratification guidelines, can be successful and improve identification and prophylaxis of this population.

Adolescent↗