[Validity of occupational stress and decision latitude on health in the National Population Health Survey of 1994-95]. / Validité des indices de demande psychologique et de latitude décisionnelle utilisés dans l'Enquête nationale sur la santé de la population (ENSP) de 1994-95.

Psychosocial environment at work is now considered a health determinant. The National Population Health Survey (NPHS) of 1994-95 is the first study in which psychological demands and decision latitude at work were measured in a random sample of the Canadian population. However, psychometric properties of the scales used in NPHS to measure these factors are not known. The objective of the present paper was to evaluate some validity parameters of the scales used in the NPHS by comparison to the original scales recommended by Karasek to measure these factors. Results of the current study support the validity of the decision latitude scale. However, validity of the psychological demand scale is more limited.

[Impact of occupational stress on health status in Canada]. / Les contraintes psychosociales au travail chez les Canadiennes et les Canadiens.

Studies have shown that high psychological demands and low decision latitude may be involved in the development of major health problems. The objective of the current study was to describe the importance of these factors among the Canadian working population. The sample included 7,250 participants from the National Population Health Survey (NPHS) of 1994-95. Women were significantly more exposed than men to high psychological demands (56% versus 49%), to low decision latitude (61% versus 49%), and to these two factors simultaneously (33% versus 22%). The exposure to each of these factors was more frequent among younger and less educated people. Simultaneous exposure to both factors was more frequent among younger people and those with intermediate education level. There was a socio-economic gradient for the exposition to these factors. Some jobs with the highest exposure were identified.

Prospective evaluation of cardiac risk indices for patients undergoing noncardiac surgery.

BACKGROUND: Prediction of perioperative cardiac complications is important in the medical management of patients undergoing noncardiac surgery. Several indices have been developed to aid prediction, but their performance has not been systematically compared. OBJECTIVE: To compare four existing methods for predicting perioperative cardiac risk. DESIGN: Prospective cohort study. SETTING: Two teaching hospitals in London, Ontario, Canada. PATIENTS: 2,035 patients referred for medical consultation before elective or urgent noncardiac surgery. MEASUREMENTS: Myocardial infarction, unstable angina, acute pulmonary edema, or death. The indices were compared by examining the areas under their respective receiver-operating characteristic (ROC) curves. RESULTS: Cardiac complications occurred in 6.4% of patients. The area under the ROC curve was 0.625 (95% CI, 0.575 to 0.676) for the American Society of Anesthesiologists index, 0.642 (CI, 0.588 to 0.695) for the Goldman index, 0.601 (CI, 0.544 to 0.657) for the modified Detsky index, and 0.654 (0.601 to 0.708) for the Canadian Cardiovascular Society index. These values did not significantly differ. CONCLUSIONS: Existing indices for prediction of cardiac complications perform better than chance, but no index is significantly superior. There is room for improvement in our ability to predict such complications.

Psychosocial factors at work, smoking, sedentary behavior, and body mass index: a prevalence study among 6995 white collar workers.

This cross-sectional study examined whether psychosocial factors at work were associated with smoking, sedentary behavior, and body mass index. The study population was composed of 3531 men and 3464 women employed as white collar workers in 21 organizations. Data were collected at worksites. Psychological demands and decision latitude at work were measured with the Karasek 18-item questionnaire. Smoking, sedentary behavior, and mean body mass index were compared by quartiles of decision latitude and psychological demands and by job strain categories. Prevalence of smoking, mean number of cigarettes smoked per day, prevalence of sedentary behavior, and mean body mass index were not consistently associated with decision latitude, psychological demands, or high job strain. However, prevalence of smoking was elevated in women belonging to the highest quartile of psychological demands (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.0 to 1.6) and in the active job strain groups in both men (OR, 1.6; 95% CI, 1.2 to 2.1) and women (OR, 1.4; 95% CI, 1.0 to 2.0). Prevalence of sedentary behavior was elevated in men in the lowest quartile of decision latitude (OR, 1.3; 95% CI, 1.0 to 1.7), in the passive group (OR, 1.3; 95% CI, 1.0 to 1.5), and in the high strain group (OR, 1.2; 95% CI, 1.0 to 1.6). In women, this prevalence was elevated in the third quartile of psychological demand (OR, 1.3; 95% CI, 1.1 to 1.6). These results provide only partial support for an association between some psychosocial factors at work and the prevalence of smoking and sedentary behavior.

The utility and prediction of allogeneic blood transfusion use in orthopedic surgery.

It is possible to predict the likelihood of postoperative blood transfusion using patient variables. The information could be used to target the high-risk group for intervention(s) that would subsequently reduce the risk of exposure to allogeneic blood. The cost of several of the alternatives to allogeneic blood precludes their use on all surgical patients, and hence the need to identify those patients who are most likely to benefit from such therapy. Further research is needed to assess the impact of predictive models on the use of allogeneic blood and costs. Research is also needed to clarify the impact of blood transfusion on perioperative morbidity and mortality, in patients with and without heart disease. If such an association does indeed exist, then an optimal hemoglobin or transfusion threshold is needed to guide clinicians in caring for their patients.

[Internal consistency, factorial validity and discriminant validity of the French version of the psychological demands and decision latitude scales of the Karasek "Job Content Questionnaire"]. / Cohérence interne, validité factorielle et validité discriminante de la traduction française des échelles de demande psychologique et de latitude décisionnelle du "Job Content Questionnaire" de Karasek.

BACKGROUND: The job demands-control model developed by Karasek has greatly influenced research on psychosocial factors at work and health. Validity of the English version of the psychological demands and decision latitude scales is documented. Psychometric qualities of the French version are investigated here in a representative sample of the general population, including blue-collars and white-collars. METHODS: The French translation of the psychological demand and decision latitude scales was administered by interview in a representative sample of the Quebec working population (N = 1,110). Internal consistency and factorial validity of the instrument were studied among white-collars and blue-collars separately. Discriminant validity was assessed for the whole population. RESULTS: Cronbach alpha coefficients, varying between 0.68 and 0.85, support the internal consistency of the scales. Demographic distribution of the scales and intercorrelations were consistent with the English version. Results of the factor analysis were consistent with the two dimensions expected from the theory. Mean scale scores and variations in the prevalence of high psychological demands combined with low decision latitude by age, sex, education, and job category support the discriminant validity of the instrument. CONCLUSIONS: Results support internal consistency, factorial validity, and discriminant validity of the French version of the psychological demands and decision latitude scales of the Karasek "Job Content Questionnaire" for white-collars and for blue-collars of the general population.

Clinical criteria for the use of a decision-making framework for the medically compromised patient: hypertension and diabetes mellitus.

In this article, clinical criteria for the staging of disease severity in patients with hypertension and diabetes mellitus are presented. This paper is intended to supplement a previous article by the authors on the use of clinical criteria for the classification of patients with ischemic heart disease and chronic obstructive pulmonary disease and the use of a decision-making framework for the medically compromised patient. Hypertension and diabetes mellitus are discussed in terms of pathophysiology, risk factors, clinical manifestations of disease and disease progression. The article will allow practitioners to stage patients with hypertension and diabetes mellitus and to apply this staging to the previously established clinical decision-making framework for medically compromised patients.

Prospective validation of a point score system for predicting blood transfusion following hip or knee replacement.

BACKGROUND: The purpose of this study was to validate a previously published point score system for predicting the likelihood of a postoperative blood transfusion following hip or knee replacement. STUDY DESIGN AND METHODS: Data were collected prospectively on 460 sequential patients undergoing elective hip and knee replacement at two academic hospitals. Blood transfusion frequency was determined for patients in each of the four risk strata, as defined by the point score system. The accuracy of the system was validated by calculating the area under the receiver operating characteristic (ROC) curve for each site. Data were then combined and inappropriate blood transfusions were eliminated, by using the American College of Physicians guidelines. The frequencies of blood transfusion within each strata were recalculated along with an ROC curve. RESULTS: The point score system accurately predicted the likelihood of blood transfusion at both hospitals, despite marked differences in overall transfusion frequencies. The calculated areas under the ROC curves were 0.78 and 0.79 for the two sites. The point score system also proved valid when only appropriate blood transfusions were considered, with a calculated area under the ROC curve of 0.74. CONCLUSION: The point score system can accurately predict the likelihood of postoperative blood transfusion following hip or knee replacement. Such a system can be used to target high-risk patients for preoperative autologous blood donation.

A clinical decision making framework for the medically compromised patient: ischemic heart disease and chronic obstructive pulmonary disease.

The intent of this article is to assist dentists and their staff in the assessment of systemic disease, and establish a framework for clinical decision making that correlates medical risk with the anticipated complexity of the planned dental procedures. Two examples of systemic disease, ischemic heart disease (IHD) and chronic obstructive pulmonary disease (COPD), are discussed in terms of pathophysiology, risk factors, clinical manifestations of disease and disease progression.

A point score system for predicting the likelihood of blood transfusion after hip or knee arthroplasty.

BACKGROUND: Given the high cost of autologous blood donation for elective surgery, it would be desirable to predict which patients are most likely to benefit from the procedure. The purpose of this study was to develop a point score system for predicting the likelihood of blood transfusion in hip and knee arthroplasty. STUDY DESIGN AND METHODS: A database of 599 patients undergoing elective surgery at a teaching hospital was used for the analysis. Variables were analyzed to determine their univariate association with postoperative blood transfusion. Significant factors were entered into a multiple logistic regression model, and a point score system was developed on the basis of the regression coefficients. Four strata of transfusion risk were constructed. RESULTS: Factors independently associated with blood transfusion included preoperative hemoglobin, type of arthroplasty, primary versus revision surgery, autologous donor status, and patient weight. Four factors were used to create a point score system with four strata. The likelihood of blood transfusion for patients in the four risk strata was 1.7, 11.0, 40.0, and 78.3 percent. The calculated area under the receiver operating characteristic curve was 0.86. CONCLUSION: The likelihood of a postoperative blood transfusion can be predicted by using this simple point score system. Autologous blood donation can subsequently be targeted to the high-risk patients.

Does it matter how coronary projections are combined to assess restenosis following PTCA?

Three methods were used to combine measurements from biplane coronary views to assess restenosis following PTCA. The first 153 patients from the EMPAR trial with 118 measurable coronary stenoses were chosen for this study. The mean difference between the RAO and LAO projections used was 88 +/- 22 degrees (S.D.). There was no systematic difference in coronary dimensions between RAO and LAO views for the group. Coronary restenosis was primarily defined as loss of 50% or more of the luminal diameter gain from the procedure. The ratio of luminal loss to gain was calculated for each stenosis using (Method 1) only the lesser diameter of the two views, (Method 2) an average of the two views and, (Method 3) a calculated cross-sectional coronary lumen area. Rates of restenosis calculated in this way ranged between 36 and 44% amongst the three methods, which was not significantly different. However, individual coronary lesions might be classified as either restenosed or not by this formula, depending on which method was used to integrate the biplane coronary measurements.

Implementation of guidelines for preoperative laboratory investigations in patients scheduled to undergo elective surgery.

OBJECTIVE: To assess the impact on preoperative laboratory investigations in elective surgery after the implementation of guidelines for ordering such tests. DESIGN: A retrospective chart audit. SETTING: A university teaching hospital. PATIENTS: The charts of 903 patients who underwent an elective surgical procedure from each surgical specialty except cardiovascular and thoracic. INTERVENTIONS: Implementation of guidelines for preoperative laboratory investigations. MAIN OUTCOME MEASURES: Impact on the preoperative use of laboratory investigations after implementation of the guidelines as well as patient morbidity and mortality. RESULTS: The mean number of preoperative laboratory investigations done per patient decreased from 4.65 before implementation of the guidelines to 4.18 after (p < 0.001). There was no apparent adverse impact on patient morbidity or mortality. CONCLUSION: Implementation of guidelines for preoperative laboratory investigations for elective surgery resulted in a reduction in the number of tests without adverse impact on patient morbidity or mortality.

Primary localized amyloidosis of the lacrimal glands.

Primary localized amyloidosis causing bilateral lacrimal enlargement is rare. The pathogenesis of amyloid deposition within the orbit and other body tissues has not been fully elucidated. The authors report the case of a 72-year-old woman who presented with bilateral lacrimal gland enlargement secondary to amyloid infiltration. The chemical nature of the deposit was characterized using light microscopy, immunohistochemistry, and immunoelectron microscopy. The primary (immunocytic) nature of the amyloid was confirmed by immunohistochemistry demonstrating the presence of monoclonal lambda light chains in the amyloid deposits and in the plasma cells. Using immunoelectron microscopy, amyloid deposits were seen containing lambda light chains in macrophages. It has been postulated that the macrophage has a role in amyloid deposition. The authors believe this to be the first published report of immunoelectron microscopy use in orbital amyloidosis, and that this technique has helped further their understanding of the nature and pathogenesis of this condition.

Comparison of ioxaglate with diatrizoate in angiography of the internal mammary artery.

To compare ioxaglate with the traditional agent diatrizoate, 44 patients scheduled to undergo coronary angiography that included internal mammary artery (IMA) visualization were entered into a randomized double blind-parallel design protocol. Complete data were collected on 32 out of 44. Four patients were withdrawn because of angiographically normal coronary arteries; seven, because of unsuccessful IMA cannulation; and one, because of an anaphylaxis-like reaction to ioxaglate. No other serious adverse effects were seen with either agent. The major endpoints were patient and physician assessments of discomfort, rated independently on a 4-point scale. Ioxaglate caused significantly less discomfort (n = 17, median rating of "mild discomfort") than did diatrizoate (n = 15, median rating of "severe discomfort"; P less than 0.01); this effect was independent of patient sex, the number of injections, and the volume of dye injected. Radiographic quality was good with both agents. We conclude that ioxaglate is much better tolerated than diatrizoate during angiography of the IMA.