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PubMed1981

The junior hospital doctors' pay dispute 1975-1976: an analysis of events, issues and conflicts.

In late 1975, for the first time in the history of the National Health Service, junior hospital doctors in the United Kingdom took industrial action. Their pay and working conditions were basic issues, but the dispute was complex. The first part of this article describes these complexities - the significant events, and the grievances and their resolution. In the second part the dispute is analysed in terms of its causes, effects and implications, particularly for the medical profession. The ambivalence, confusion and ignorance about the new contract and the question of breaking government pay policy, problems of representation, and conflicts of interests within the profession are highlighted. It is suggested that the significant economic gains of the junior doctors were not achieved by industrial action.

Conflict, Psychological↗
PubMed1983

A study of mental retardation in children in the Island of Hawaii.

Eighty-one probands from an initial population of 223 school-aged retarded individuals were assessed by history, clinical examination and, where appropriate, cytogenetic analysis. In 51 individuals, the retardation occurred as an isolated event within the family, whereas 30 patients had a family history of retardation. In 39 of the isolated individuals, the retardation was either related to environmental factors or associated with a major neurological abnormality. The remaining 12 patients were phenotypically normal with no cytogenetic abnormality. Of the 30 probands from 15 families with a history of retardation, 3 families had X-linked syndromes. One, with 4 proband daughters, had the mar(X) syndrome and two families were considered to have the phenotypically similar syndrome but without demonstrating the mar(X). In an additional 5 families, the distribution and clinical features of the affected individuals were compatible with nonspecific X-linked mental retardation.

Child↗
PubMed2002

Smoking status and risk for recurrent coronary events after myocardial infarction.

BACKGROUND: Questions remain about the importance of smoking and smoking cessation after incident myocardial infarction. OBJECTIVE: To assess the association between smoking status and risk for recurrent coronary events. DESIGN: Retrospective, population-based, inception cohort study. SETTING: Health maintenance organization from 1986 to 1996. PATIENTS: 2619 persons who survived to hospital discharge after a first myocardial infarction. MEASUREMENTS: Relative risk (RR), assessed by using Cox proportional hazards regression analysis, for recurrent coronary events in nonsmokers (persons with no history of smoking), former smokers (persons who had stopped smoking before infarction), quitters (persons who stopped smoking after infarction), and active smokers (persons who continued smoking after infarction). RESULTS: At the time of incident infarction, 33.6% of patients were nonsmokers, 35.5% were former smokers, and 30.9% were active smokers. Of the 808 persons who were active smokers at the time of incident infarction, 449 quit smoking during hospitalization or after discharge. With nonsmokers as the reference group, the multivariable RR for recurrent coronary events (n = 433) was 1.17 (95% CI, 0.93 to 1.43) for former smokers and 1.51 (CI, 1.10 to 2.07) for active smokers. Among quitters, the RR decreased as duration of cessation increased: With nonsmokers as the reference group, the RR for quitters was 1.62 (CI, 1.02 to 2.61) if the duration of cessation was 0 to less than 6 months, 1.60 (CI, 0.97 to 2.60) if the duration was 6 to less than 18 months, 1.48 (CI, 0.76 to 2.51) if the duration was 18 to less than 36 months, and 1.02 (CI, 0.54 to 1.86) if the duration was 36 months or more (P = 0.01 for trend). CONCLUSION: After incident myocardial infarction, smoking was associated with an elevated risk for recurrent coronary events. In persons who quit smoking after infarction, the risk declined to equal that of nonsmokers by 3 years after cessation.

Adult↗
PubMed1988

Physical inactivity as a risk factor for primary and secondary coronary events in Göteborg, Sweden.

Physical activity at work and during leisure time were studied by using a questionnaire in a random sample of 7495 middle-aged men from the Primary Prevention Study in Göteborg and in 1273 able-bodied male patients with a first myocardial infarction, registered in the Infarction Register in the same city over the period 1968-84. Data on coronary risk factors and socio-economic factors were recorded in the population sample as were data on risk factors and known somatic predictors for prognosis in the infarction group. An inverse and graded association was found between leisure time physical activity and mean diastolic blood pressure, total cholesterol, body mass index, tobacco smoking, socio-economic status and mental stress in the random sample. During the approximate 12-year follow-up, low physical activity during leisure time, but not at work, was associated with an increased risk of coronary deaths and non-fatal infarctions in univariate analysis. Inactive subjects had twice the incidence of total coronary events (9.4%) as physically active contemporaries (4.2%). After controlling for major coronary risk factors, occupational class, diabetes, family history of coronary heart disease and mental stress in a multivariate logistic regression analysis, the association between leisure time physical activity and total coronary events disappeared. Physical activity at work and during leisure time estimated for the 12-month period preceding the first infarction was not associated with long-term prognosis after infarction. Infarction patients assessed to be in need of additional rehabilitation due to somatic restrictions, work-related factors and emotional instability, resumed work later and had a higher mortality and non-fatal recurrence rate during follow-up than patients not considered to require additional rehabilitation. Physical inactivity was not a risk factor for primary and secondary coronary events in this study. The inverse direction of the association between leisure time physical activity and coronary risk factors suggests that increased physical activity alters the risk factor profile in a favourable direction.

Activities of Daily Living↗
PubMed1996

Prevalence and correlates of symptomatic peripheral atherosclerosis in individuals with coronary heart disease and cholesterol levels less than 240 mg/dL: baseline results from the Cholesterol and Recurrent Events (CARE) Study.

PURPOSE: To determine the prevalence and correlates of symptomatic peripheral atherosclerosis in individuals with a history of myocardial infarction (MI) and cholesterol levels lower than 240 mg/dL. MATERIALS AND METHODS: A cross-sectional analysis was conducted at baseline of 4159 participants in the Cholesterol and Recurrent Events (CARE) Study. Symptomatic diffuse atherosclerosis was defined as a history of MI plus lower extremity or cerebrovascular atherosclerosis or claudication by Rose questionnaire. RESULTS: The prevalence of symptomatic diffuse atherosclerosis was 12.9%; 353 participants (8.5%) had lower extremity disease and 219 (5.3%) had cerebrovascular disease. After controlling for other variables, diffuse atherosclerosis was associated with age (Odds Ratio [OR] = 1.44 per ten-year increase), systolic blood pressure (OR = 1.13 per 10 mm Hg increase), a history of multiple myocardial infarctions (OR = 1.76), diabetes (OR = 1.76), hypertension (OR = 1.38), reduced exercise performance (OR = 1.55), current smoking status (OR = 2.87), and lower alcohol intake (OR = 0.97 per drink per week). There was no association with race, gender, or lipid levels. CONCLUSIONS: The presence of clinically evident diffuse atherosclerosis is common and is associated with several modifiable risk factors. Early identification of these individuals could affect treatment and clinical outcomes.

Anticholesteremic Agents↗
PubMed2004

Prognostic value of dobutamine stress echocardiography in patients with systemic hypertension and known or suspected coronary artery disease.

Currently, there are no outcome data to suggest an incremental value of stress echocardiography in the risk stratification of patients who have hypertension after controlling for the left ventricular mass index (LVMI). This study assessed the incremental value of dobutamine stress echocardiography (DSE) for the prediction of mortality rate and cardiac events in patients who have hypertension. We studied 596 patients who had hypertension (mean age 62 +/- 12 years; 382 men) and who underwent DSE for evaluation of known or suspected coronary artery disease. End points during follow-up were hard cardiac events (cardiac death and nonfatal myocardial infarction) and total mortality rate. Left ventricular hypertrophy was detected by echocardiography in 119 patients (20%). During a median follow-up of 3 years, 101 patients (17%) died (43 cardiac deaths) and 19 patients had nonfatal myocardial infarction. In an incremental multivariate analysis model, clinical predictors of hard cardiac events were age, history of congestive heart failure, and LVMI. The percentage of abnormal myocardial segments examined with DSE was incremental to the clinical model (chi square 41 vs 27, p <0.001). Clinical predictors of total mortality rate were age, smoking, hypercholesterolemia, history of congestive heart failure, and LVMI. The peak wall motion score index was incremental to the clinical model (chi square 45 vs 40, p <0.05). DSE provides incremental data for the prediction of mortality rate and hard cardiac events in patients who have hypertension after adjustment for clinical data and LVMI.

Cardiotonic Agents↗
PubMed2005

Cortical blindness: clinical and radiologic findings in reversible posterior leukoencephalopathy syndrome: case report and review of the literature.

PURPOSE: To alert ophthalmologists to the recognition of cortical visual loss as the presenting feature in patients with reversible posterior leukoencephalopathy syndrome (RPLES). Unique radiologic findings are paramount to the diagnosis. DESIGN: Interventional case report. METHODS: A patient was seen with perioperative bilateral cerebral visual loss that was misinterpreted initially as an irreversible ischemic event. Further detailed analysis of the radiologic findings and clinical history led to the correct diagnosis. MAIN OUTCOME MEASURES: Visual acuity and magnetic resonance imaging (MRI) of the brain. RESULTS: Recognition of the correct diagnosis of RPLES led to the institution of antihypertensive therapy and recovery of normal vision. CONCLUSIONS: The diagnosis of RPLES should be considered in all patients with acute cerebral visual loss, especially in the setting of recent surgery, blood transfusion, chemotherapy, immunosuppressant use, hypertension, eclampsia, or seizures. Prompt diagnosis requires close collaboration with a radiologist and an emergent MRI study, which ideally should include diffusion-weighted imaging with calculation of an apparent diffusion coefficient map. Differentiation from acute cerebral ischemia is important in order to avoid permanent visual loss by prompt and vigorous treatment of exacerbating factors such as intermittent hypertension. Prompt diagnosis will also help to avoid potentially dangerous invasive procedures such as thrombolytic therapy.

Adult↗
PubMed1993

Psychiatric and social aspects of brittle asthma.

BACKGROUND: Many studies have shown that emotional factors play a part in asthma, but few have compared patients with differing severities of asthma. It was our impression that patients with "brittle" asthma (BA; more than 40% diurnal variation in peak flow on 15 or more days a month over a period of at least six months, and persistent symptoms despite multiple drug treatment) had greater psychosocial morbidity than asthmatic patients with less variable asthma. METHODS: Twenty patients with BA and a control group of less severe asthmatic subjects matched for age, sex, and duration of illness were asked to complete the General Health Questionnaire (GHQ), a screening test for psychiatric disorders, the Eysenck Personality Inventory which measures extraversion and neuroticism, and to participate in a life events interview and a structured clinical interview (SCID) to diagnose psychiatric disorder. RESULTS: The mean (SD) age was 45.6 (12.3) years for the BA group, and 45.7 (13.1) years for the control group. All patients were receiving inhaled steroids and regular beta 2 agonists; nine patients with BA but no control patients were taking oral steroids, and 12 of the patients with BA but no controls were receiving beta 2 agonists by subcutaneous infusion or injection. Eight of the patients with BA scored more than 11 on the GHQ compared with five of the control group (NS). Significantly more subjects with BA (12/20) than controls (5/20) had intercurrent or past psychiatric disorder, and 7/20 subjects with BA had a lifetime history of anxiety disorder compared with 3/20 controls. Life events analysis showed no overall difference in the total number, but the patients with BA had significantly more life events related to asthma. There was no difference in personality profiles between the two groups. CONCLUSIONS: The results suggest that patients with "brittle" asthma have greater psychiatric morbidity than those with less severe asthma, but that their personality profiles and overall life event experiences are similar.

Adult↗
PubMed1991

Insulin resistance in the oral glucose tolerance test--a link with hypertension.

Insulin resistance was evaluated in 807 middle-aged subjects at a health survey, with use of an index measured in 75 g oral glucose tolerance tests. The mean value of insulin resistance was higher in a hypertensive group than among the normotensives, independent of body mass index, physical activity, smoking sex, age, and thiazide treatment. One-third of the hypertensives had a high resistance value. Another third of the hypertensives, and also about one-third of the normotensives, had a slightly increased resistance. The remaining third of the hypertensives had a normal-low resistance. A high resistance was also independently related to obesity, low physical leisure time activity, and a family history of NIDDM, but not to a family history of hypertension. The statistical analysis implied a sequence of events: low physical activity might cause high resistance, which in turn might cause high blood pressure.

Age Factors↗
PubMedDate not supplied

[Identification of the horizontal gene transfer based on phylogenetic data].

We suggest a new procedure to search for the genes with horizontal transfer events in their evolutionary history. The search is based on analysis of topology difference between the phylogenetic trees of gene (protein) groups and the corresponding phylogenetic species trees. Numeric values are introduced to measure the discrepancy between the trees. This approach was applied to analyze 40 prokaryotic genomes classified into 132 classes of orthologs. This resulted in a list of the candidate genes for which the hypothesis of horizontal transfer in evolution looks true.

Algorithms↗
PubMed1994

Overview of methodological issues in the study of chronic care populations.

The intent of the methodology section of this volume was to provide an overview of recent thinking about analytic techniques that can be used to study chronic care populations, particularly dementia SCUs. As discussed earlier in this article, although not unique to these populations, longitudinal analysis of chronic care populations frequently involves several problems: nonequivalent comparison groups, unbalanced designs, censoring and attrition, autocorrelation (correlated repeated measures) and heterogeneous correlations across repeated measures. The last 5 years has witnessed considerable change and growth in the development of longitudinal modelling methodologies. Although developments in modelling cut across disciplines, there has been a focus on certain types of methods in several fields of applied statistics: psychometrics (e.g., analysis of change, item response theory, Rasch modelling of binary outcomes), mathematical sociology (e.g., structural equation modelling), demography (e.g., transition modelling), epidemiology (e.g., risk modelling), and biostatistics (e.g., examination of intervention effects using marginal and random effects modelling of repeated measures). An important issue is the interrelationship between measurement and outcome assessment. Source of measurement error must be considered (see Zimmerman and Magaziner in this volume), as must bias in assessments (see Teresi and Golden in this volume). While it has long been known that poor measurement can attenuate and bias estimates of longitudinal effects, the answer is not to attempt artificial solutions through use of corrections for attenuation (unreliability). Design and sampling issues are also critical to the correct conduct of any longitudinal study. Otherwise, estimates of prevalence, incidence, and intervention effects will be in error (see Beckett and Evans, in this volume). Several modelling approaches have been reviewed. Different points of view regarding change analysis have been presented; controversy remains regarding the "best" methods for examining change (see the commentary by Rogosa in this volume). Theory building using methods such as structural equation modelling remains a staple of longitudinal analysis, although several caveats have been discussed. New or revisited methodologies (random effects modelling, of which growth curve analysis can be viewed as a special case and event history modelling) offer promise in dealing with the knotty problems inherent in the longitudinal study of chronic care populations, namely, censoring, attrition, and unbalanced designs resulting in missing data (see the commentary by Nesselroade, in this issue). However, it remains clear that no one model or approach will be optimal for all applications.

Activities of Daily Living↗
PubMed2001

Genetics and the population history of Europe.

Analysis of genetic variation among modern individuals is providing insight into prehistoric events. Comparisons of levels and patterns of genetic diversity with the predictions of models based on archeological evidence suggest that the spread of early farmers from the Levant was probably the main episode in the European population history, but that both older and more recent processes have left recognizable traces in the current gene pool.

Alleles↗
PubMed2004

Infections and atopy: an exploratory study for a meta-analysis of the "hygiene hypothesis".

BACKGROUND: According to the "hygiene hypothesis" selected allergic diseases could be prevented by exposure to infectious agents during early childhood. METHODS: This study was performed to assess the feasibility of a future meta-analysis on the "hygiene hypothesis" and atopic diseases. Differences concerning the potential association with a history of infectious events, in terms of magnitude and homogeneity of global risk estimates between the three major atopic diseases (i.e. atopic dermatitis, asthma and allergic rhinitis) were examined. We conducted a preliminary analysis on a sample of articles published on this topic and cited in a recent and authoritative review. RESULTS: The ranges of relative risks estimates (between 0.6 and 0.8) were similar for atopic dermatitis, allergic rhinitis and asthma. Compared with asthma and allergic rhinitis, reported global risk estimates were more stable for atopic dermatitis (lowest heterogeneity). Our analysis suggests that three main categories of indirect markers of exposure to infection can be identified: 1) geographical gradient, 2) indices of potential contact with infectious agents (such as number of siblings) and 3) history of infectious events. CONCLUSIONS: In this exploratory study, we chose articles cited in a single review and obtained a preliminary quantification of the association between infections and atopic diseases. The association with indirect markers of infection corresponded to 20% protection for atopic dermatitis, 30% for allergic rhinitis and 40% for asthma. In a subsequent meta-analysis, diseases should be considered separately and differences between types of exposures should be taken into account as one of the major end-points, with attention to time since exposure and disease onset.

Asthma↗
PubMed2002

[Prognostic factors in unstable angina with dynamic electrocardiographic changes. Value of fibrinogen].

INTRODUCTION AND OBJECTIVES: The prognosis of unstable angina varies between series depending on the inclusion criteria and management protocol used. The aim of this study was to analyze in-hospital events and their predictors in a homogeneous single-center series of patients with unstable angina. MATERIAL AND METHODS: A total of 246 patients with the following inclusion criteria were studied: 1) resting anginal pain, 2) transient electrocardiographic changes during anginal pain, 3) normal CK-MB levels and 4) exclusion of postinfarction angina. All patients were treated with aspirin and enoxaparin (1 mg/kg/12 h). Coronary angiography was performed in the case of recurrent angina or ischemia in Bruce I-II stage during the predischarge effort stress test. The variables recorded were risk factors, history of ischemic heart disease, history of coronary surgery, ECG upon admission, and fibrinogen. RESULTS: During the hospital stay the following events were recorded: 36% recurrent angina, 58% cardiac catheterization, and 5,7% major events (infarction or death). Multivariate analysis found recurrent angina to be more frequent in patients with a history of coronary bypass surgery (p = 0.004. OR = 22; CI 95%, 3-182), ST-segment changes (p = 0.01. OR = 4.7, CI 95%; 1.4-15.9) and higher fibrinogen (p = 0.002. OR = 1,4, CI 95%; 1.1-1.7). Fibrinogen was the only variable related to cardiac catheterization (p = 0,009. OR = 1.3. CI 95%, 1.1-1.6) and major events (p = 0.001. OR = 2.0. CI 95%, 1.4-3.1). CONCLUSIONS: 1) Unstable angina with electrocardiographic changes was associated to a high rate of in-hospital events. 2) Fibrinogen was related to any event, and previous by-pass surgery and ST changes were related to recurrent angina.

Aged↗
PubMed2001

[A four-year prospective study on the influence of serum elevated lipoprotein (a) concentration on ischemic heart disease and cerebral infarction in elderly patients with type 2 diabetes].

To clarify the influence of elevated serum lipoprotein (a) (Lp(a)) concentration on ischemic heart disease (IHD) and the perforating artery occlusion type of cerebral infarction (CI) in elderly patients with type 2 diabetes, we measured the serum levels of Lp(a) of type 2 diabetic patients (n = 158, 81 men and 77 women). The group was followed up prospectively for 4 years and the incidence of IHD or CI was monitored. The diagnosis of CI was confirmed by computed tomography and that of IHD, which includes myocardial infarction and angina pectoris, was diagnosed by electrocardiogram and blood chemistry examination, Lp(a) concentrations of 20 mg/dl or more were identified as elevated Lp(a) levels and Lp(a) concentrations of less than 20 mg/dl were identified as normal Lp(a) levels. A Kaplan-Meier survival analysis (log-rank test) assessed the time to event rate stratified by an Lp(a) cutoff point of 20 mg/dl. The predictive value for CI or IHD events was assessed by multiple logistic regression analysis. The probability of IHD events was significantly higher in the elevated Lp(a) group than in the normal Lp(a) group without a history of IHD but was similar in the two groups for those patients with a history of IHD. There was no significant difference between the elevated Lp(a) group and the normal Lp(a) group with regard to CI events in patients without a history of CI and with a history of CI. On multiple logistic regression analysis, Lp(a), hyperlipidemia and a history of IHD were significant predictors of IHD and hypertension, hyperlipidemia and a history of CI were significant predictors of CI. These results show that elevated serum Lp(a) concentrations is an independent risk factor for IHD, but not for the perforating artery occlusion type of CI in type 2 elderly diabetic patients.

Aged↗
PubMed2005

Non-homogeneous Markov processes for biomedical data analysis.

Some time ago, the Markov processes were introduced in biomedical sciences in order to study disease history events. Homogeneous and Non-homogeneous Markov processes are an important field of research into stochastic processes, especially when exact transition times are unknown and interval-censored observations are present in the analysis. Non-homogeneous Markov process should be used when the homogeneous assumption is too strong. However these sorts of models increase the complexity of the analysis and standard software is limited. In this paper, some methods for fitting non-homogeneous Markov models are reviewed and an algorithm is proposed for biomedical data analysis. The method has been applied to analyse breast cancer data. Specific software for this purpose has been implemented.

Algorithms↗
PubMed1990

Additional prognostic value of exercise testing and thallium-201 scintigraphy in catheterized patients without previous myocardial infarction.

To determine whether exercise testing and thallium scintigraphy provide additional prognostic information in symptomatic patients undergoing catheterization, we studied 432 consecutive male patients without a previous myocardial infarction by means of an exercise test, thallium scintigraphy and catheterization. The follow-up period was 46 +/- 24 months (from 12 to 96). Events were defined as death (27 patients), nonfatal myocardial infarction (occurring in 27 patients) or late (greater than 60 days after test) surgery or dilatation (needed in 45 patients). The 5 year survival rate was 89% and the event-free rate was 72%. History, noninvasive and invasive variables were submitted to a stepwise Cox regression analysis. By multivariate analysis, the significant variables related to death were the number of diseased vessels and exercise workload; the selected variables for all cardiac events were the number of diseased vessels; the score at thallium exercise testing and exercise workload. Among the subgroups of 337 coronary patients, the predictive variables for death were exercise workload and the number of diseased vessels. For all cardiac events, the selected variables were the number of diseased vessels, the score of defects during thallium exercise and exercise workload. Thus, in patients without a previous myocardial infarction, noninvasive variables do provide prognostic information which is not available either from the history or from catheterization.

Cardiac Catheterization↗