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PubMed2000

Relationship between blood pressure level and mortality rate: an 18-year study conducted in two rural communities in Japan.

BACKGROUND: There have been very few studies on life prognosis of cardiovascular disease according to blood pressure stratification in the Japanese. Therefore, in Japan, although treatment of hypertension is possible, albeit at times difficult, due to the availability of various antihypertensive medications, the appropriate time at which treatment should be started remains a problem. OBJECTIVE: To investigate the long-term prognosis of cardiovascular disease in the Japanese general population according to blood pressure stratification in the Japanese. DESIGN: A community-based prospective cohort study of 1996 men and women between the ages of 40 and 64 years at the baseline examination was conducted over an 18-year period. Information on death was obtained from local public health nurses and death certificates. The causes of death were clarified by questionnaires sent to doctors in the hospital in which the deceased was hospitalized, and the causes of death were analysed in each blood pressure category at baseline examination. RESULTS: Mortality from cardiovascular disease increased with increases in the level of blood pressure and was significantly higher in > or = 140 mmHg group in systolic blood pressure and > or = 90 mmHg group in diastolic blood pressure, adjusted for age, sex and other cardiovascular risk factors in the Japanese general population. However, mortality risk from cardiovascular disease did not have a J-shaped relationship with systolic and diastolic blood pressure. CONCLUSION: We conclude that the optimum time for starting treatment in Japanese people is when blood pressure is 140/90 mmHg or less.

Adult↗
PubMed1991

Risk stratification and outcome assessment of the adult cardiac surgical patient.

Comparisons between institutions are already occurring, and comparisons between individual providers may also become a reality. In spite of the negative views of such comparisons, they are likely to be mandated because of pressure from health care regulators, insurers, and patients. Despite awareness of the importance of demographic variables and concurrent medical problems in influencing outcome, valid comparisons are presently difficult to conduct in the open heart surgical population. Current methods of risk stratification each have limitations. A method for risk assessment based on multivariate analysis from a large group of patients that can be prospectively validated at multiple institutions would be valuable, not only for mortality rate comparisons, but also for patient counseling, research, and hospital management uses. Caution must be applied when using risk assessment in individual patients. Physicians need to be involved in the development of such severity stratifying systems, since inclusion of inappropriate or medically irrelevant data can influence the outcome of multivariate analyses. Ongoing research and evolution of scoring systems also need to occur since therapy changes over time. It is likely that models will need to be developed for application preoperatively, at ICU admission, and for the complex, long-term patient at 7 days or beyond, in order to fully inform medical decision-making.

Adult↗
PubMed2004

Methods and design considerations for randomized clinical trials evaluating surgical or endovascular treatments for cerebrovascular diseases.

OBJECTIVE: The results of clinical trials affect the practice of surgery and endovascular therapy for cerebrovascular diseases. The purpose of this report is to review the basic components of the designs and methods for randomized clinical trials and to describe the influence of those components on the interpretation of trial results. METHODS: The goal of an optimal clinical trial of a new procedure is to provide the most objective and rigorous evaluation of the safety and effectiveness of that procedure. Anything in the design, performance, or analysis that impairs such an assessment decreases the ability of the trial to achieve its goal and answer the research question. To highlight the components of a clinical trial, this report uses examples of Phase III clinical trials that have influenced the practice of cerebrovascular surgery and endovascular therapy in the past three decades, including the International Cooperative Study of Extracranial/Intracranial Arterial Anastomosis, the North American Symptomatic Carotid Endarterectomy Trial, the Asymptomatic Carotid Atherosclerosis Study, the Prolyse in Acute Cerebral Thromboembolism II study, and the International Subarachnoid Aneurysm Trial. RESULTS: The research question (objective) of the trial must be clearly defined, with an objective measure of efficacy and a specified quantitative difference to define the superiority of one intervention over another, in a relatively homogeneous patient population. Allocation concealment, randomization with or without stratification, and blinding (or masking) are important strategies to prevent differences in the study populations that could adversely affect the conclusions of the study. The primary end point must correspond to the specific aims of the trial. It should be objectively defined, quantifiable, reliable, and reproducible. Commonly defined end points in surgical trials include changes from baseline illness or disease severity scores, morbidity and mortality rates, and relative risks of reaching an end point with time. The statistical methods used for interim and final analyses are important. The effects of dropouts, crossovers, and missing data should be understood in the context of the final analysis. Additional concepts, such as intention-to-treat analysis and use of actual versus predicted outcomes, are important with respect to interpretation of the final results of the study. CONCLUSION: The neurosurgical and neuroendovascular communities are currently planning or conducting several clinical trials to evaluate new procedures for the treatment of cerebrovascular diseases. It is hoped that a better understanding of the components of clinical trials will facilitate the design and implementation of effective studies.

Angioplasty↗
PubMed1992

[Risk stratification in patients recuperating from acute myocardial infarct. How useful is it?].

The author intended to discuss the individual prognostic value of some best known risk stratification variables after Acute Myocardial Infarction (AMI), whose tests have a low diagnostic accuracy due to high risk individual variations, emphasizing the statistic errors of using one single risk variable on post AMI risk stratification schemes. Some epidemiologic data about AMI survivors are reviewed and the author concludes by emphasizing the importance of using more AMI population characteristics on post AMI risk stratification schemes.

Arrhythmias, Cardiac↗
PubMedDate not supplied

Prevalence of artificial hip implants and use of health services by recipients.

Data from the 1988 Medical Device Implant Supplement to the National Health Interview Survey are used to summarize information about the prevalence of artificial hips among adults in the United States. The 1988 National Health Interview Survey was a cross-sectional survey of the civilian noninstitutionalized United States population, and included 122,310 persons in 47,485 households in a multistage probability sample. The supplement supplied the first population-based estimates of prevalence and morbidity of selected medical devices. Projected to the United States population, the survey results indicate that an estimated 674,000 adults were using 811,000 hip implants. Hip implant recipients were significantly more likely to be older, to be white, and to have lower educational, income, and activity levels than the general population of adults. After age-stratification, however, only differences in activity limitation and race remained. Current economic outlays for hip replacement surgery are substantial. With the aging population, use of health services by patients with artificial hips will probably increase unless measures to reduce the need for replacement surgery are instituted. These measures include reducing injuries and improving biomaterials. Further investigation is needed to examine the activity limitation and racial difference in prevalence found in this study.

Activities of Daily Living↗
PubMed2006

C-reactive protein and echocardiography have little impact on risk stratification in never-treated hypertensive patients.

The aim of this study was to assess the contribution of increased concentrations of high-sensitivity C-reactive protein (hsCRP) and echocardiography to risk stratification according to the 2003 European guidelines for the management of arterial hypertension in patients with untreated hypertension. A total of 207 consecutive medical outpatients with untreated hypertension were included. History and clinical examination, electrocardiography, laboratory analyses including the measurement of hsCRP and echocardiography were performed in all patients. Patients were classified into four risk groups with and without using echocardiography and hsCRP concentrations of at least 10 mg/l according to the 2003 guidelines for the management of hypertension. The majority of the 207 patients (81%) were at moderate or high cardiovascular risk before adding echocardiography and/or hsCRP to the risk stratification process. When echocardiography was included, only three patients were reclassified from the moderate added risk to the high added risk group. Adding hsCRP concentrations of at least 10 mg/l had no impact on risk stratification. Using an hsCRP cutoff level of 3 mg/l, one patient was at moderate instead of low added risk, eight patients were at high instead of moderate added risk and one patient was at very high instead of high added risk. We conclude that hsCRP at the proposed cutoff level of 10 mg/l has no impact on risk stratification in outpatients with untreated hypertension. An hsCRP cutoff level of 3 mg/l may be more suitable for risk stratification. Finally, our data suggest that depending on the population studied, there is minimal impact of echocardiography on risk stratification.

C-Reactive Protein↗
PubMed2004

Bradykinin B2 receptor gene C-58T polymorphism and insulin resistance. A study on obese patients.

The bradykinin B2 receptor (B2R) gene is a candidate in the pathogenesis of insulin resistance, which often clusters with other abnormalities in metabolic syndrome. We investigated the distribution of the C-58T B2R gene polymorphism within a population of overweight/obese patients (BMI > or = 25 kg/m2) potentially characterised by different levels of insulin resistance. Patients with type 2 diabetes, dyslipidemia and hypertension were excluded in order to distinguish the effect of obesity on insulin sensitivity from that of confounding factors. Ninety-two unrelated adults (41 men and 51 women, aged 33.7 +/- 11.6 years) were recruited by random sampling from a general population evaluated for cardiovascular risk stratification. Measurements included BMI, waist circumference, body composition, blood pressure, serum leptin, and lipid profile. Insulin sensitivity was calculated according to the homeostasis model assessment (HOMA) method. C-58T genotypes--CC (n = 20), CT (n = 47) and TT (n = 25)--were determined by restriction fragment-length polymorphism PCR. Patients subdivided on the basis of C-58T polymorphism, showed no difference in any of the parameters examined, including HOMA index values, after adjustment for age, sex, BMI and waist circumference. The results indicate that the C-58T B2R gene polymorphism is not associated with different levels of insulin resistance within a population of obese patients.

Adult↗
PubMed1995

Sudden death in athletes.

HCM, as well as coronary and myocardial structural abnormalities, is the most common pathology leading to SCD in young athletes. Furthermore, SCD from fatal arrhythmia seems to be the most common mechanism of death. In this population, however, data are insufficient to support either invasive or noninvasive approaches to clarify risk stratification for SCD. Because of the large population, variants of normal found within the athletic population, and the rarity of the disease, screening for individuals at risk is neither practical nor cost-effective. Not all athletes with HCM are at the same risk for SCD; a thorough history and physical examination should alert the health professional to potential risk factors. Efforts are under way to stratify athletes at risk for SCD to determine who can participate in competitive sports and who should not. However, until research can accurately define variables of hemodynamic and electrical instability that permit reliable identification of athletes with HCM who are at risk for SCD, the recommendation is to disqualify athletes with confirmed HCM from moderate- to high-intensity competitive sports. This recommendation includes athletes with or without symptoms or left ventricular outflow obstruction. Due to the decreased risk of SCD in older athletes, individual judgment of eligibility may be used. Athletes thought to have had myocarditis should be withdrawn from all competitive sports for a convalescent period of approximately 6 months, with thorough cardiac assessment and testing performed before returning to training. Athletes with atrial or ventricular tachyarrhythmia must be screened for structural abnormality, heart response during exercise, and the frequency and duration of the arrhythmia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2003

Incidence and prediction of nonmelanoma skin cancer post-renal transplantation: a prospective study in Queensland, Australia.

BACKGROUND: Nonmelanoma skin cancer (NMSC) is a significant clinical problem after renal transplantation, particularly in areas of high UV light exposure. A single-center prospective study of a population of Queensland renal transplant recipients was performed with the aims of: (1) establishing NMSC incidence and tumor accrual post-renal transplantation, and (2) developing a clinically derived predictive index to identify transplant recipients at greatest risk. METHODS: Three hundred ten of 398 transplant recipients (78%) who underwent baseline assessment between July 1999 and April 2000 were reassessed a mean of 18 +/- 3.5 (SD) months later. A structured interview, full skin examination, biopsy of suspicious lesions, and review of medical and pathological records were used to determine the number and types of NMSC arising between the two assessments. Incidence (percentage of the population developing NMSC per year) and tumor accrual (number of tumors per person per year) were calculated. A clinically derived predictive index was generated using stepwise logistic regression models. RESULTS: Overall NMSC incidence was 28.1% and increased with duration of immunosuppression therapy: 18.8%, 24.8%, 33.3%, and 47.1% at less than 5, 5 to 10, 10 to 20, and greater than 20 years of immunosuppression therapy, respectively. Mean NMSC accrual was 1.85 +/- 3.84 tumors/person/y, increasing to 3.35 +/- 4.29 tumors/person/y after 20 years of immunosuppression therapy. Renal transplant recipients were stratified into categories of high and low NMSC risk by using predictive indices. CONCLUSION: Clinically derived predictive indices can allow NMSC risk stratification of an Australian transplant population and may provide an evidence-based and cost-effective approach to developing a targeted clinical NMSC surveillance program.

Adult↗
PubMed2002

Validation of an algorithm for predicting cardiac events in renal transplant candidates.

A 2-tiered noninvasive cardiac risk stratification algorithm was first evaluated in a test population with planar thallium myocardial perfusion imaging and subsequently in a validation population using single-photon emission computed tomographic (SPECT) thallium myocardial perfusion imaging. This study examines if SPECT imaging was as predictive of cardiac death as planar imaging and also if SPECT imaging predicted nonfatal cardiac events in the patient population. Renal transplant candidates were evaluated using a 2-tiered noninvasive cardiac risk stratification algorithm. The first tier of risk assessment utilized 5 variables: age >50 years, insulin-dependent diabetes mellitus, abnormal electrocardiogram, and a history of either angina or congestive heart failure. Patients without risk factors were considered low risk and underwent no further cardiac evaluation. Patients with > or =1 risk factor were considered high risk and underwent a second tier of risk assessment with planar (n = 95) or SPECT (n = 112) imaging. In the test population, 13 of 16 cardiac deaths (81%) occurred in high-risk patients with abnormal planar studies. In the validation group, all cardiac deaths (5 of 60) and nonfatal cardiac events (13 of 60) occurred in high-risk patients with abnormal SPECT studies. SPECT imaging was at least as predictive as planar imaging and also predicted nonfatal as well as fatal cardiac events. Pretransplant risk stratification by clinical variables identified low-risk patients who may not require further cardiac evaluation and high-risk patients with normal SPECT imaging who may not require angiography.

Adult↗
PubMed2002

Incidence and case fatality rates of stroke subtypes in a multiethnic population: the South London Stroke Register.

OBJECTIVE: To identify sociodemographic differences in the incidence of the subtypes of first ever stroke in a multiethnic population. METHODS: A prospective community stroke register (1995-8) was developed using multiple notification sources and pathological and clinical classifications of stroke. Standardisation of rates was to European and World populations and adjusted for age, sex and socioeconomic status in multivariate analyses. A multiethnic population of 234 533 in south London, of whom 21% are black was studied. RESULTS: A total of 1254 cases were registered. The average age of stroke was 71.7 years with black patients being 11.3 years younger than white patients (p<0.0001). The incidence rate/1000 population was 1.33 (crude) (95% CI 1.26 to 1.41), 1.28 (European adjusted) (95% CI 1.2 to 1.35) with a 2.18 (95% CI 1.86 to 2.56) (p<0.0001) age and sex adjusted incidence rate ratio in the black population. Radiological diagnosis was confirmatory in 1107 (88.3%) with 862 (68.7%) infarction, 168 (13.4%) primary intracerebral haemorrhage, and 77 (6.2%) subarachnoid haemorrhage. Of the cerebral infarction cases 189 (21.9%) were total anterior circulatory, 250 (29%) partial anterior, 141 (16.4%) posterior (POCI) and 282 (32.7%) lacunar infarcts. The black group had a significantly higher incidence of all subtypes of stroke except for POCI and unclassified strokes. The incidence rate ratio (IRR) for men compared with women was 1.34 (95% confidence interval (95% CI) 1.19 to 1.50; p<0.001). The IRR for manual versus non-manual occupations in those aged 35-64 years was 1.64 (95%CI 1.22 to 2.23; p<0.0001). There was a borderline significant increase in adjusted survival at 6 months in the black group 95% (CI 0.61 to 1.03, p=0.078) with a hazard ratio of 0.79 after adjustment and stratification. CONCLUSIONS: Although the black population is at increased risk of stroke and most subtypes of stroke, this is not translated into significant differences in survival. Hence black/white differences in mortality are mainly driven by incidence of stroke. There are striking demographic inequalities in the risk of stroke in this multiethnic inner city population that need to be tackled through interagency working. Although the reasons for the increased risk in the black population are unclear, demographic factors such as socioeconomic status do seem to play a significant independent part.

Adolescent↗
PubMed2006

The health of nations in a global context: trade, global stratification, and infant mortality rates.

Despite the call for a better understanding of macro-level factors that affect population health, social epidemiological research has tended to focus almost exclusively on national-level factors, such as Gross Domestic Product per capita (GDP/c) or levels of social cohesion. Using a world-systems framework to examine cross-national variations in infant mortality, this paper seeks to emphasize the effects of global trade on national-level population health. Rather than viewing national-level health indicators as autonomous from broader global contexts, the study uses network analysis methods to examine the effects of international trade on infant mortality rates. Network data for countries were derived from international data on the trade of capital-intensive commodities in 2000. Using automorphic equivalence to measure the degree to which actors in a network perform similar roles, countries were assigned into one of six world-system blocks, each with its own pattern of trade. These blocks were dummy-coded and tested using ordinary least squares (OLS) regression. A key finding from this analysis is that after controlling for national-level factors, the two blocks with the lowest density in capital-intensive exchange, i.e., the periphery, are significantly and positively associated with national-level infant mortality rates. Results show the effects of peripherality and stratification on population health, and highlight the influence of broader macro-level factors such as trade and globalization on national health.

Commerce↗
PubMed1989

Short- and long-term clinical outcome after Q wave and non-Q wave myocardial infarction in a large patient population.

Prognosis for patients with non-Q wave myocardial infarction is controversial although a number of studies have shown a less favorable outlook after hospital discharge for patients with non-Q wave than for those with Q wave infarction. Therefore, the in-hospital and 1-year prognosis was investigated in a sufficiently large patient population (n = 2,024) to allow stratification by subgroups, in particular by age and previous myocardial infarction. Patients with non-Q wave infarction (n = 444; 22% of the total study population) were somewhat older (65 vs. 63 years, p less than 0.001) and had an increased incidence of previous myocardial infarction (46% vs. 24%, p less than 0.001) and congestive heart failure (21% vs. 8%, p less than 0.001) than patients with Q wave infarction. In-hospital mortality of patients with non-Q wave infarction was lower (8.1% vs. 11.5%; p less than 0.06), whereas their 1-year mortality after hospital discharge was significantly higher (13.7% vs. 9.2%, p less than 0.05) than for patients with Q wave infarction. However, total mortalities at 1 year were nearly equal. When patients were subgrouped by presence or absence of a previous myocardial infarction, patients in both subgroups exhibited mortality patterns typical of the entire population with Q wave or non-Q wave infarction. However, when stratified by age and previous infarction, in-hospital mortality for patients with non-Q wave infarction was significantly lower only in patients older than 70 years of age. Similarly, the higher mortality after hospital discharge in patients with non-Q wave infarction occurred only in patients older than 70 years of age without previous myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed2006

Familial clustering in subgroups of gastric cancer stratified by histology, age group and location.

AIM: To assess the risk of gastric cancer in a Japanese patient population with the disease by stratification with histology, age, tumour location and the association with family history of gastric or non-gastric tumours. METHODS: A retrospective analysis of 1400 consecutive patients with gastric cancer and 13,467 age- and gender-matched controls from a pre-recorded database using conditional logistic regression models. RESULTS: Young patients (< or = 43 years of age) with gastric cancer of intestinal type had a strong association with family history of gastric cancer in first degree-relatives (OR=12.5). Moreover, when a history of gastric cancer was observed in both parents, there was an increased risk of gastric cancer intestinal type (OR=7.8), more commonly in the proximal and mid-stomach. In contrast, there was an increased risk of diffuse-type cancer when both parents suffered non-gastric cancers (OR=2.1). CONCLUSION: These data suggest that the degree of familial clustering differ in gastric cancer subgroups stratified by histology, age, and stomach location in this Japanese population.

Age Distribution↗
PubMed2006

Surgical management of infective endocarditis: early predictors of short-term morbidity and mortality.

BACKGROUND: Infective endocarditis is a diagnostic and therapeutic challenge that ultimately requires surgical intervention in 20% of all cases. Early determinants of morbidity and mortality in this high risk population are not well described. METHODS: The aim of this study was to determine preoperative clinical, microbiological, electrocardiographic, and echocardiographic variables that predicted the need for permanent pacemaker implantation and in-hospital death in a surgical cohort of patients with active infective endocarditis. RESULTS: We identified 91 patients (61 males and 30 females, mean age 58 +/- 16 years) who underwent surgical intervention for active culture-positive infective endocarditis as defined by the Duke criteria. Native valve infective endocarditis was present in 78 (85.7%) and prosthetic valve endocarditis in 13 (14.3%) of cases. The aortic valve was infected in 61 (67.0%), the mitral in 35 (38.5%), and multiple valves in 8 patients (8.8%). The most common indication for surgical intervention was intractable heart failure. Twenty-two patients (24.2%) required pacemakers, while there were 14 (15.4%) in-hospital deaths. In age-adjusted and gender-adjusted analyses, the presence of left bundle branch block on preoperative electrocardiogram (ECG) and presence of depressed left ventricular systolic function (ejection fraction [EF] < 50%) predicted the need for a permanent pacemaker implantation, while the presence of depressed left ventricular function predicted in-hospital mortality. CONCLUSIONS: Preoperative ECG findings of left bundle branch block and reduced left ventricular function may allow for early risk stratification of this high risk population.

Adult↗
PubMed1983

The epidemiology of admissions to the child and adolescent psychiatric outpatient clinic.

Using the data from the 1970 census of population and housing for the Standard Metropolitan Statistical Area (SMSA) of Milwaukee, Wisconsin (1), demographic information was recorded for each of the approximately 300 census tracts in Milwaukee County pertaining to the population characteristics, marital status, age stratification, and economic and housing characteristics. Also, information was collected on the number of admissions into the child and adolescent outpatient clinic for each census tract. The 300 census tracts were than divided into four categories: very low admission, low admission, high admission, and very high admission. Using a computer method, a demographic analysis of these four groups of census tracts was then carried out to examine the correlation between the census tracts was then carried out to examine the correlation between the density of admissions and various demographic characteristics. During the course of the study, various correlations between high admissions to the child and adolescent psychiatric outpatient clinic and various demographic characteristics emerged. Implications of these findings, in terms of present service and future planning, are discussed.

Adolescent↗
PubMed1993

Effect of age, birth cohort and period of death on Italian liver cirrhosis mortality, 1972-1986.

Liver cirrhosis is one of the main causes of death in Mediterranean countries. A trend towards a global reduction in the mortality rate has been recently reported. In order to clarify better this trend and in an attempt to hypothesize the future pattern of mortality, we analysed data from 254,834 Italian subjects aged 30-79 who died from liver cirrhosis during the period 1972-1986. We used a log-linear Poisson model to examine the effects of age, calendar period of death and birth cohort. Our data confirm that both in the population as a whole and after stratification for three geographical areas (Northern, Central and Southern Italy) the mortality rate is decreasing. The age-effect analysis showed an exponentially rising effect in the Southern population, in accordance with the viral aetiology of cirrhosis, whereas an increased effect followed by a decreased effect was observed in the Northern and Central population, suggesting the alcoholic aetiology for the disease. The results from the birth-cohort effect suggested that in the Northern and Central populations mortality should continue to decrease over the next decade, possibly due to the implementation of better prevention programmes for cirrhotics and to decreased alcohol consumption in Italy. In the Southern population, however, mortality is still rising and this will probably continue for the next decade, as the generations born between 1940 and 1950 who are at high risk of carrying chronic hepatitis B virus infection, reach the age of higher risk of death from liver cirrhosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Population genetics of three VNTR polymorphisms in two different Spanish populations.

Two different Spanish populations, one from Galicia (NW Spain) and the other from the rest of Spain, have been analyzed at three different hypervariable loci (YNH24, MS43a and MS31) using the EDNAP electrophoretic protocol and HinfI as restriction enzyme. Although the "rest of Spain" population is a clearly stratified population using classical blood groups, no evidence of stratification for these loci has been found and the differences to the Galician population were not significant, which suggests that a common Spanish population data-base could be possible. A semiparametric model is proposed for estimating frequencies, using the smoothed cross-validation of Hall et al. (1992) to calculate the size of the window utilized.

Alleles↗