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C L Soskolne

Publications and source records attributed to C L Soskolne.

At least 19 recordsLinked to original sources
PubMed2003

Lack of associations between air emissions from sour-gas processing plants and beef cow-calf herd health and productivity in Alberta, Canada.

This paper describes a large-scale investigation into the effects of licensed air emissions from sour-gas processing plants on the health and productivity of beef cow-calf herds in the province of Alberta, Canada. In conjunction with a geographical information system, two atmospheric-dispersion models were used to assess historical exposures at 5726 beef cow-calf farm-sites from 1987 to 1990. We did secondary analyses of health, productivity, and management data, from a government-extension survey previously administered to beef cow-calf producers across the province. Statistical models (adjusted for potential confounding and clustering within herd and over time) were used to determine associations with estimates of sour-gas emission exposure. All analyses were conducted at the herd-level. There were no significant (P>0.05) detrimental associations of exposure and the annual herd risk for culling, calf-crop delivered, calf-crop season profile, stillbirth and twinning, calfhood mortality, or calf-crop weaned.

Air Pollutants↗
PubMed2003

Air emissions from sour-gas processing plants and dairy-cattle reproduction in Alberta, Canada.

The dispersion of air pollutants from all 231 licensed sour-gas processing plants in Alberta, Canada, was modeled on a monthly basis over a 10-year period (1985-1994). Exposure estimates for sulfur dioxide (SO(2)-used as a surrogate for exposure to combusted emissions) then were assigned to 1382 provincial dairy farms using a geographical-information system. Individual average and peak exposure for periods prior to each of 15 months of age and conception (four exposure-averaging periods for each of two dispersion models) were estimated for 163,988 primiparous female dairy-cattle between 1986 and 1994. Monthly or annual average farm-site exposure estimates likewise were assigned to associated herd-level data sets for the biologically relevant period of interest for each of three additional reproductive outcomes: monthly herd-average calving interval, stillbirth risk, and twinning risk. In one of the main-effects models, the maximum (i.e., peak) monthly sour-gas exposure experienced by individual-animals from birth to conception was associated with an increased time to first-calving in the very-highest exposure category (hazard ratio=0.86, 95% CI=0.80, 0.92). This equates to a decreased hazard (lambda) of calving (in each month subsequent to 22 months of age) for the highest-exposure animals (lambda=0.170) versus the zero-exposure animals (lambda=0.198) in a model with referent values for agro-ecological region and season of birth. The dose-response was not consistent across the full range of exposure categories. There was significant (P=0.003) interaction of emissions with agro-ecological region. After accounting for the interaction, a more-consistent dose-response was evident for some (but not all) agro-ecological regions. This suggests that any effect of emissions on dairy-heifer reproduction is subject to modification by features of soil type, vegetative cover, and/or climate. The increase in monthly herd-average calving interval on farms exposed to the very-highest levels of emissions appeared quite small and of limited practical importance within the range of expected exposures. There was no association between exposure and the risk for twinning. Herds exposed to higher emissions exhibited a slight decrease in risk for stillbirth.

Aging↗
PubMed2001

Modeling changes in health perception following hip fracture.

BACKGROUND AND OBJECTIVE: Health perception is an important outcome associated with health-related quality of life. Various correlates of perceived health have been identified, but attempts at multivariate modeling have often failed to mirror the complex system of causal pathways surrounding this concept. The objective of this study was to develop a multivariate model to improve our understanding of how physical, social, and psychological factors interact to influence health perception following a hip fracture. METHODS: Patients were interviewed in-hospital during the week following the fracture to obtain information on in-hospital mental status and pre-fracture function, pre-fracture health perception, and pre-fracture social support. A follow-up interview was conducted by telephone to assess function, health perception, and social support 3 months post-fracture. Comorbidities and demographic information were obtained from medical records. RESULTS: This study included 222 hip fracture patients aged 65 + and fracturing a hip between 10 July 1996 and 30 August 1997. Our estimated model was theory-based, developed from existing research identifying the following correlates of health perception: physical function, comorbidities, socioeconomic status, social support, age, and prior health perception. In addition to these correlates, our model was unique in incorporating a variable to assess whether the gap between pre- and post-fracture functioning acted as a separate cause on post-fracture health perception. Initially, the fit between the data and the model was poor, however minor modifications to the model corrected this. While there was a good fit between the data and the estimated model, only about 25% of the variation in both pre- and post-fracture health perceptions were explained. The number of comorbidities and physical function were found to have the strongest influence on health perception. Post-fracture health perceptions were also improved by increased post-fracture social support, higher income/status, and higher pre-fracture health perception. The network of effects indicates that the causal sources of health perception may differ in the pre- and post-fracture periods. This suggests that the causal sources of health perception following major health changes may differ substantially from the causal sources of health perception operating during normal times. CONCLUSIONS: The findings suggest that interventions aimed at improving pre-fracture function and post-fracture social support could increase health perception following hip fracture. In interpreting our results, it is important to remember that while we attempted to adjust for measurement error in the analysis, the study may be limited due to the retrospective nature of the questions. Future research should focus on improving the model by including other components of the patient's emotional health.

Aged↗
PubMed2001

Prevalence and determinants of tuberculin reactivity among physicians in Edmonton, Canada: 1996-1997.

BACKGROUND: Health care workers (HCW) have historically borne a heavy burden of tuberculosis (TB) infection and disease. Unfortunately, physicians are rarely included in HCW surveys of tuberculin exposure and infection. METHODS: The prevalence and risk factors for tuberculin reactivity were determined for a sample of the 1732 licensed physicians in Edmonton. Stratified random sampling was used to select 554 specialists and 219 general practitioners. These physicians were contacted by means of an introductory letter and a follow-up telephone call to solicit participation. All eligible physicians were asked to complete a questionnaire and those with either no recorded positive tuberculin test or a previously negative result were two-step tuberculin skin tested. RESULTS: In total, 560 physicians (72.4 %) participated in the study. The overall tuberculin reactivity for this population was 45.9%. Using logistic regression analysis, we determined that risk factors for reactivity were aged over 45 years, of foreign-birth, previous Bacillus Calmette-Guérin (BCG) vaccination, foreign practice experience, and being a respiratory medicine specialist. CONCLUSION: The prevalence of tuberculin reactivity among physicians is considerably higher than estimates for the general Canadian population. This observed excess risk may be associated with factors linked to their medical practice. The high participation rate suggests physician willingness to participate in this type of research, and emphasizes the need to include them in routine HCW surveillance.

Alberta↗
PubMed2001

Toward measuring the impact of ecological disintegrity on human health.

Ecological integrity refers to the ability of environmental life-support systems to sustain themselves in the face of human-induced impacts. We used a correlational, aggregate-data study design to explore whether life expectancy, as a general measure of population health, is linked to large-scale declines in ecological integrity. Most of the data were obtained from World Resources Institute publications. Selected surrogate measures of ecological integrity and gross domestic product (GDP) per capita (as a socioeconomic confounder) were modeled, for the first time, using linear regression techniques with life expectancy as the health outcome. We found a modest relation between ecological integrity and life expectancy, but the direction of the association was inconsistent. When GDP per capita was controlled, the relation between ecological integrity and life expectancy was lost. GDP per capita was the overwhelming predictor of health. Any relation between ecological integrity and health may be mediated by socioeconomic factors. The effect of declines in ecological integrity may be cushioned by the exploitation of ecological capital, preventing a direct association between measures of exposure and outcome. In addition, life expectancy may be too insensitive a measure of health impacts related to ecological decline, and more sensitive measures may need to be developed.

Cross-Sectional Studies↗
PubMed2001

Functional dependence after hip fracture.

OBJECTIVES: To identify patients at high risk of functional dependence and examine the progression of disability after a hip fracture. DESIGN: This was a population-based prospective inception cohort study of all patients aged 65+ yr who fractured a hip between July 1996 and August 1997. Demographic, socioeconomic, social support, and health status information was assessed in the hospital and 3 mo postfracture. RESULTS: The analysis included 367 patients. Almost all patients with cognitive impairment were functionally dependent postfracture, with new disabilities frequently occurring in transferring. Among patients of high mental status, increased risk of functional dependence was associated with advanced age, more co-morbidities, hip pain, poor self-rated health, and previous employment in a prestigeous occupation. Bathing disability was most likely in those who functioned independently prefracture; a disability in dressing was most common otherwise. CONCLUSION: Hip pain is amenable to treatment and may improve chances of functional recovery. Patients can be assisted in regaining prefracture function if they are targeted for rehabilitation on the basis of mental status. The focus should be on bathing and dressing among patients of high cognition and transferring among those patients with mental impairment.

Activities of Daily Living↗
PubMed2000

Mortality and institutionalization following hip fracture.

OBJECTIVES: To identify determinants of mortality and institutionalization after hip fracture and to identify those older hip fracture patients at high risk of death or institutionalization after hip fracture. DESIGN: Population-based prospective inception cohort study of hip fracture patients; patients were assessed in the hospital and at 3 months following the hip fracture. SETTING: Edmonton area hip fracture patients admitted to one of two Edmonton, Alberta, Canada, acute care centers between July 10, 1996, and August 31, 1997. PARTICIPANTS: Patients were residents of the Edmonton area and over the age of 64. Those who had previously fractured the same hip within the past 5 years or had some pathological condition underlying the hip fracture were excluded. Of 610 eligible patients, 558 contributed some baseline information and were included in the mortality analysis; the institutionalization analysis was restricted to the 338 patients who lived in the community before fracture, survived the 3-month period postfracture, and had completed a 3-month follow-up interview. MEASUREMENTS: The baseline interview was done in the hospital to assess mental status, prefracture physical function, prefracture health perception, and prefracture social support. The 3-month follow-up interview was done by phone to assess physical function, health perception, and social support 3 months postfracture. Demographic and comorbidity information was collected from medical records. RESULTS: Low mental status in hospital was found to increase the chances of mortality and institutionalization, and male gender was found to increase mortality risk fourfold. Each additional 10 years of age increased the risk of institutionalization approximately 2.5 times. Patients with lower postfracture physical function had at least five times the risk of institutionalization compared to patients with high postfracture physical function. CONCLUSIONS: Cognitive impairment, older age, and gender were associated with increased risk of poor outcome following hip fracture. The socioeconomic variables--social support and health perception--did not contribute significant additional information in explaining mortality or institutionalization risk. While demographic factors cannot be modified, physical function 3 months postfracture may be amenable to intervention and may reduce the risk of institutionalization. Intervening to increase postfracture physical function may be particularly beneficial to older patients, or to those who are cognitively impaired.

Aged↗
PubMed1998

Findings from the American College of Epidemiology's survey on Ethics guidelines. The American College of Epidemiology Ethics and Standards of Practice Committee.

PURPOSE: A survey to establish both the need and subject areas for a possible new set of ethics guidelines for epidemiologists was conducted among a random sample of 300 North American (Canada, Mexico, and United States) members of three major United States-based professional epidemiology organizations. METHODS: An 88% response rate revealed wide agreement on topics to be included in any new set of guidelines, but uncertainty prevailed about the need for new guidelines; 41% agreed that there was a need to develop a new set, 43% had no opinion, and 16% disagreed. RESULTS: There was almost no difference in preferences between men and women for topics to be included in a new set of guidelines, or between those aware or unaware of extant ethics guidelines in epidemiology. Fifty-four percent were aware of such guidelines and only 29% of these said they could describe the content of the guidelines. CONCLUSION: More needs to be done to evaluate the utility of ethics codes in epidemiology.

Data Collection↗
PubMed1998

Surgeon-related factors and outcome in rectal cancer.

OBJECTIVE: To determine whether surgical subspecialty training in colorectal surgery or frequency of rectal cancer resection by the surgeon are independent prognostic factors for local recurrence (LR) and survival. SUMMARY BACKGROUND DATA: Variation in patient outcome in rectal cancer has been shown among centers and among individual surgeons. However, the prognostic importance of surgeon-related factors is largely unknown. METHODS: All patients undergoing potentially curative low anterior resection or abdominoperineal resection for primary adenocarcinoma of the rectum between 1983 and 1990 at the five Edmonton general hospitals were reviewed in a historic-prospective study design. Preoperative, intraoperative, pathologic, adjuvant therapy, and outcome variables were obtained. Outcomes of interest included LR and disease-specific survival (DSS). To determine survival rates and to control both confounding and interaction, multivariate analysis was performed using Cox proportional hazards regression. RESULTS: The study included 683 patients involving 52 surgeons, with > 5-year follow-up obtained on 663 (97%) patients. There were five colorectal-trained surgeons who performed 109 (16%) of the operations. Independent of surgeon training, 323 operations (47%) were done by surgeons performing < 21 rectal cancer resections over the study period. Multivariate analysis showed that the risk of LR was increased in patients of both noncolorectal trained surgeons (hazard ratio (HR) = 2.5, p = 0.001) and those of surgeons performing < 21 resections (HR = 1.8, p < 0.001). Stage (p < 0.001), use of adjuvant therapy (p = 0.002), rectal perforation or tumor spill (p < 0.001), and vascular/neural invasion (p = 0.002) also were significant prognostic factors for LR. Similarly, decreased disease-specific survival was found to be independently associated with noncolorectal-trained surgeons (HR = 1.5, p = 0.03) and surgeons performing < 21 resections (HR = 1.4, p = 0.005). Stage (p < 0.001), grade (p = 0.02), age (p = 0.02), rectal perforation or tumor spill (p < 0.001), and vascular or neural invasion (p < 0.001) were other significant prognostic factors for DSS. CONCLUSION: Outcome is improved with both colorectal surgical subspecialty training and a higher frequency of rectal cancer surgery. Therefore, the surgical treatment of rectal cancer patients should rely exclusively on surgeons with such training or surgeons with more experience.

Adenocarcinoma↗
PubMed1997

Equal treatment: bestowed or earned?

PURPOSE: While the complaint against non-industry employed epidemiologists for holding their industry-based colleagues to a higher level of scrutiny is accurate, this paper shows that there is a sound basis for such treatment. It also shows, however, that a shift towards ongoing vigilance is needed on the part of all epidemiologists to guard against such bias. METHODS: The proposed shift is made possible through the recent incorporation in ethics guidelines of principles that indeed identify the impropriety of any such bias. RESULTS: In the same guidelines, there are principles that require scientific impartiality. Industry-based epidemiologists, by the condition of their employment, may find the avoidance of partiality to the corporate interest more problematic than do non-industry based epidemiologists to their respective sponsors. It is in light of past examples of partiality among industry-based epidemiologists that other epidemiologists may be biased against them. CONCLUSIONS: This paper concludes with the realization that both groups of epidemiologists have the challenge of correcting the biases inculcated over many years. Trust needs to be established between industry and non-industry-based epidemiologists through greater acceptance on the part of the latter and exemplary conduct on the part of the former to overcome past practice records.

Bias↗
PubMed1997

Ethical, social, and legal issues surrounding studies of susceptible populations and individuals.

Calls for professional accountability have resulted in the development of ethics guidelines by numerous specialty and subspecialty groups of scientists. Indeed, guidelines among some health professions now address vulnerable and dependent groups: but these are silent on issues related to biomarkers. In parallel, attention has been drawn to human rights concerns associated with attempts to detect hypersusceptible workers, especially in democratic countries. Despite this, concern for vulnerable populations grows as advances in biomarker technology make the identification of genetic predisposition and susceptibility markers of both exposure and outcome more attainable. In this article, the principles derived from the ethical theory of utilitarianism provide the basis for principle-based ethical analysis. In addition, the four principles of biomedical ethics--respect for autonomy, beneficence, nonmaleficence, and social justice--are considered for biomarker studies. The need for a context in which ethical analysis is conducted and from which prevailing social values are shown to drive decisions of an ethical nature is emphasized; these include statutory regulation and law. Because biomarker studies can result in more harm than good, special precautions to inform research participants prior to any involvement in the use of biomarkers are needed. In addition, safeguards to maintain the privacy of data derived from biomarker studies must be developed and implemented prior to the application of these new technologies. Guidelines must be expanded to incorporate ethical, social, and legal considerations surrounding the introduction of new technologies for studying susceptible populations and individuals who may be vulnerable to environmental exposures.

Biomarkers↗
PubMed1995

Use of second line drugs for the treatment of rheumatoid arthritis in Edmonton, Alberta. Patterns of prescription and longterm effectiveness.

OBJECTIVE: Our purpose was to compare the patterns of prescription of 2nd line drugs for the treatment of rheumatoid arthritis (RA) among rheumatologists in Edmonton, Alberta, and to examine the longterm effectiveness of these drugs. METHODS: A 1985 inception cohort of 128 patients with RA was assessed between 1991 and 1992, using measures of disease activity, radiological scores and physical functional status. Use of different therapies was retrieved from the medical charts. RESULTS: All patients had seen a rheumatologist at any time between January, 1985 and December, 1991, 88% within the first 3 years of disease. Most (85%) had received at least one 2nd line drug, the majority within the first 2 years. Overall, gold salts were the most frequently prescribed drugs. Patterns of prescription varied among different rheumatologists; some drugs were never prescribed by some and very often by others (e.g., auranofin). Terminations because of toxicity and lack of efficacy were high. Methotrexate (MTX) had the lowest termination rate and sulfasalazine the highest, mostly due to lack of efficacy. CONCLUSION: In this cohort, patients were treated early in the course of RA. Patterns of prescription of 2nd line drugs varied among rheumatologists. Termination rates were highest for sulfasalazine and lowest for MTX.

Adrenal Cortex Hormones↗
PubMed1994

Outcome in rheumatoid arthritis. A 1985 inception cohort study.

OBJECTIVE: Our purpose was to describe the clinical status and outcome of a 1985 inception cohort of patients with rheumatoid arthritis (RA), retrospectively established. METHODS: All patients with RA in Edmonton, with a possible onset of disease in 1985, and who consulted a rheumatologist at any time from January, 1985 through June, 1991 were considered for inclusion in the cohort. Patients were contacted and assessed between August, 1991 and June, 1992. The following indices were used as outcome measures: joint counts, radiological scores of hand radiographs and the modified Health Assessment Questionnaire for activities of daily living (MHAQ). RESULTS: One hundred and twenty eight patients were included in the cohort (70% were women; age at onset was 52 +/- 13 years). At the time of the assessment, 41 patients (32%) had no articular swelling. Twenty-nine patients (23%) had a radiological score of 0, and 39 (31%) had no erosions. The mean MHAQ score was 0.49 +/- 0.47; 39 patients (31%) had a score of 0 (normal function). Rheumatoid factors and nodules were related to more severe outcomes. Sex, age at onset and mode of onset were not related to prognosis. Most patients had received 2nd line therapy within the first 3 years of RA. CONCLUSION: Our results suggest that the prognosis of RA after 6-7 years of disease is not as ominous as has been suggested by others. Since most of the previous studies have been conducted in prevalent cases attending tertiary centers, a selection bias may be responsible for some of these results. Since these patients were treated early in the course of the disease, the beneficial effects of prompt 2nd line therapy cannot be excluded.

Adult↗
PubMed1993

Cancer risk assessment and management. An ethical perspective.

We explored ethical issues in cancer risk assessment and management. Although literature about risk assessment and management is increasing, few attempts have been made to address directly either their ethical aspects or implications. We have compared ethical considerations raised at the community level with those classically considered in the physician-patient setting. Established principles of autonomy, beneficence, nonmaleficence, and distributive justice are shown not to be easily applicable at the societal level. Available information about the safety of exposures often is too scanty to allow decisional autonomy; beneficence is considered from the societal viewpoint rather than from that of the individual; and equity is frequently violated. Ethics require careful consideration when defining what is acceptable to society; the simple mathematical formulations used for risk-benefit evaluations cannot be applied directly to individuals. Further development and integration of these ideas are necessary.

Cost-Benefit Analysis↗
PubMed1993

The fluoridation of drinking water and hip fracture hospitalization rates in two Canadian communities.

OBJECTIVES: The purpose of this study was to compare hip fracture hospitalization rates between a fluoridated and a non-fluoridated community in Alberta, Canada: Edmonton, which has had fluoridated drinking water since 1967, and Calgary, which considered fluoridation in 1991 but is currently revising this decision. METHODS: Case subjects were all individuals aged 45 years or older residing in Edmonton or Calgary who were admitted to hospitals in Alberta between January 1, 1981, and December 31, 1987, and who had a discharge diagnosis of hip fracture. Edmonton rates were compared with Calgary rates, with adjustment for age and sex using the Edmonton population as a standard. RESULTS: The hip fracture hospitalization rate for Edmonton from 1981 through 1987 was 2.77 per 1000 person-years. The age-sex standardized rate for Calgary was 2.78 per 1000 person-years. No statistically significant difference was observed in the overall rate, and only minor differences were observed within age and sex subgroups, with the Edmonton rates being higher in males. CONCLUSIONS: These findings suggest that fluoridation of drinking water has no impact, neither beneficial nor deleterious, on the risk of hip fracture.

Aged↗