PubMed Health⌕ Search

Biomedical subjects

L L Lim

Publications and source records attributed to L L Lim.

At least 37 records · Page 2Linked to original sources
PubMed2000

Influence of admission body temperature on stroke mortality.

BACKGROUND AND PURPOSE: The influence of body temperature on stroke outcome remains uncertain. The aim of this study was to investigate the prognostic role of admission body temperature on short-term and long-term mortality in a retrospective cohort study of patients with acute stroke. METHODS: A retrospective cohort of 509 patients with acute stroke, admitted to a tertiary hospital between July 1, 1995, and June 30, 1997, was studied. The relationship between admission body temperature and mortality both in-hospital and at 1-year mortality was evaluated. Body temperature on admission was classified as hypothermia (</=36.5 degrees C), normothermia (>36.5 degrees C and </=37.5 degrees C), and hyperthermia (>37.5 degrees C). Logistic regression and proportional hazards function analysis were performed after adjustment for clinical predictors of stroke outcome. RESULTS: In ischemic stoke, mortality was lower among patients with hypothermia and higher among patients with hyperthermia. The odds ratio for in-hospital mortality in hypothermic versus normothermic patients was 0.1 (95% CI, 0.02 to 0.5). The relative risk for 1-year mortality of hyperthermic versus normothermic patients was 3.4 (95% CI, 1.6 to 7.3). A similar but nonsignificant trend for in-hospital mortality was seen among patients with hemorrhagic stroke. CONCLUSIONS: An association between admission body temperature and stroke mortality was noted independent of clinical variables of stroke severity. Hyperthermia was associated with an increase in 1-year mortality. Hypothermia was associated with a reduction in in-hospital mortality.

Aged↗
PubMed2000

Utility of the Charlson comorbidity index computed from routinely collected hospital discharge diagnosis codes.

This study aims to determine whether the Charlson comorbidity index computed from ICD-9-CM discharge diagnosis codes adds additional information to a model containing adjustment for more informed patient details (e.g., disease severity and history), besides solely age and sex, when predicting long-term survival. We conducted a retrospective cohort study of patients admitted to hospital for suspected acute myocardial infarction. Index scores were calculated by applying the D'Hoore et al. algorithm (1993). The index significantly improved the model fit (likelihood ratio test: p < 0.001). The D'Hoore-adapted Charlson index is a useful comorbidity risk adjustment tool when applied to AMI and angina patients.

Adult↗
PubMed1999

Variation in stated management of acute myocardial infarction in five countries.

We examined the variation in stated practice in the management of acute myocardial infarction (AMI) among doctors in Australia, Brazil, Chile, India and Thailand. Hospitals were identified as primary, secondary or tertiary by investigators from around their own region. All doctors within each hospital who would be expected to treat patients with AMI were asked to indicate which investigations and treatments they would offer to a patient with an AMI who develops angina on Day 3 after admission. The numbers of hospitals ranged from 5 to 26 per country, and doctor response rates varied from 70 to 100%. Within-country variation was large, and statistically significant variations were seen between countries in the use of most interventions. The large variation both between and within a range of countries across the economic spectrum suggests a widespread need for agreement about what constitutes appropriate management after AMI.

Australia↗
PubMed1999

Use of the 12-item short-form (SF-12) Health Survey in an Australian heart and stroke population.

The objective of this study was to validate the SF-12 Health Survey in heart and stroke patients using a community-based study. Between November 1995 and August 1996, 3,362 patients were invited to join the Hunter Heart and Stroke Register in New South Wales, Australia and to complete the SF-12 Health Survey. Of the 3,362 patients, 2,341 (70%) returned the SF-12. Of those 2,341 patients, 78% completed all 12 items. Those who did not complete the questionnaire were significantly more likely to be females, older, less educated, have stayed longer in hospital and been admitted on emergency. The SF-12 demonstrated construct validity in an analysis restricted to the 1,831 patients who completed the questionnaire: scores measuring physical and mental health status were statistically significantly higher in men than women, in younger than older, in those who had shorter than longer lengths of stay in hospital, in patients whose hospital admissions were planned than emergencies and in heart than stroke patients. Construct validity of the SF-12 among patients able to complete the SF-12 suggests considerable potential for its use in assessing health status in large-scale surveys. However, caution should be taken with the heart and stroke population because of a relatively high in completion rate.

Age Distribution↗
PubMed1999

Differences in management of heart attack patients between metropolitan and regional hospitals in the Hunter Region of Australia.

OBJECTIVES: To test the hypothesis that among patients with acute myocardial infarction (AMI) length of hospital stay, drug use in hospital and on discharge were different between metropolitan and regional hospitals after adjusting for differences in patient baseline risk. METHODS: A retrospective cohort study using a community-based register of heart attack patients assessed 1,406 patients admitted for definite AMI to three metropolitan and five regional hospitals in the Lower Hunter Region of NSW, between January 1, 1990, and March 31, 1994. RESULTS: Patients in metropolitan hospitals were significantly less likely to stay in hospital for more than seven days (adjusted odds ratio = 0.50; 95% CI 0.34-0.73), significantly more likely to receive ACE inhibitors (adj. OR = 1.47; 1.27-1.71) and less likely to receive calcium channel blocker (adj. OR = 0.70; 0.54-0.98). Regardless of disease severity, metropolitan hospitals had a higher percentage of patients for whom drugs shown to decrease mortality after AMI were used (streptokinase, aspirin, ACE inhibitor); a lower percentage of patients received drugs shown to have no benefit or even a detrimental effect (calcium channel blocker). Both groups had relatively low use of beta blocker, also shown to be of benefit. CONCLUSIONS: Regional hospitals had longer hospital stays than metropolitan hospitals and less use of drugs of proven benefit.

Adult↗
PubMed1999

Association of Helicobacter pylori infection with gastric carcinoma: a meta-analysis.

OBJECTIVE: As conflicting studies have recently been published, we aimed to determine if Helicobacter pylori (H. pylori) infection is associated with gastric adenocarcinoma. METHODS: This was a meta-analysis of observational epidemiological studies. RESULTS: A total of 42 studies met the selection criteria and were categorized by the type of study design: eight cohort and 34 case-control studies. The pooled odds ratio for H. pylori in relation to gastric carcinoma was 2.04 (95% CI: 1.69-2.45). Both patient age (OR 0.77, 95% CI: 0.68-0.89) and intestinal type cancers (OR 1.14, 95% CI: 1.05-1.25) were independent effect modifiers. Analysis of other effect modifiers showed no relationship with female gender (OR 0.76, 95% CI: 0.64-0.89), stage of cancer (advanced %) (OR 1.12, 95% CI: 0.88-1.43), anatomical location (cardia %) (OR 1.54, 95% CI: 0.32-7.39) or cohort (nested case-control) studies (OR 1.72, 95% CI: 0.32-9.17). There was significant heterogeneity among the studies (tau2 = 149; p < 0.001). The quality of the studies varied considerably, with the majority of excellent studies producing positive results and the very poor to moderate studies producing mixed results. CONCLUSIONS: H. pylori infection is associated with a 2-fold increased risk of developing gastric adenocarcinoma.

Adenocarcinoma↗
PubMed1998

Management of patients with diabetes after heart attack: a population-based study of 1982 patients from a heart disease register.

BACKGROUND: Previous studies examining the management of patients with diabetes after acute myocardial infarction (AMI) have been based on clinical studies under experimental conditions. We used data from a population-based heart disease register to document differences in the management after AMI between patients with and without diabetes. HYPOTHESIS: There were no differences in the prescription rates of aspirin, beta blockers, streptokinase, ACE inhibitors and calcium channel blockers between patients with and without diabetes admitted to hospital with AMI. METHODS: A retrospective study of 268 patients with, and 1714 patients without, diabetes discharged from hospital with 'definite' AMI between August 1988 and March 1994. RESULTS: The prescription rates of all five drug classes increased between 1988 and 1994 both for patients with and without diabetes. Patients with diabetes were significantly less likely to have been prescribed aspirin (76% vs 85%), beta blockers (41% vs 53%) and streptokinase (25% vs 43%) but more likely to have been prescribed ACE inhibitors (47% vs 29%) and calcium channel blockers (50% vs 40%). The differences in prescription rates were statistically significant after controlling for age, sex, history of ischaemic heart disease, smoking status, educational level and disease severity. CONCLUSION: Patients with diabetes were less likely to have been prescribed three of the five drug classes where evidence points to a beneficial effect after AMI. Further work is needed to identify the reasons for the disparity between management of patients with and without diabetes, and to develop effective strategies to increase the implementation of best practice guidelines in the management of patients with diabetes after AMI.

Adrenergic beta-Antagonists↗
PubMed1998

Quality of life and later adverse health outcomes in patients with suspected heart attack.

We tested the hypothesis that low quality of life (QOL) after discharge from hospital with ischaemic heart disease (IHD) is associated with higher rates of later adverse outcomes (death and subsequent hospital admission for acute myocardial infarction or congestive cardiac failure). Three hundred and seventy-five patients previously enrolled in an intervention study which assessed QOL six months after hospitalisation were followed up for an additional 18 months. The rates of adverse outcomes increased as QOL decreased (high QOL 9%; moderate 18%; low 28%). After adjustment for known prognostic factors, the risk of an adverse outcome was still higher in 'low' and 'moderate' compared to 'high' QOL subjects (low QOL adjusted OR = 2.6, 95% CI = 1.2-5.8; moderate 1.9, 0.8-4.2). In conclusion, QOL after discharge from hospital appears to be an independent predictor of later morbidity and mortality.

Adult↗
PubMed1996

Variability in risk of gastrointestinal complications with individual non-steroidal anti-inflammatory drugs: results of a collaborative meta-analysis.

OBJECTIVE: To compare the relative risks of serious gastrointestinal complications reported with individual non-steroidal anti-inflammatory drugs. DESIGN: Systematic review of controlled epidemiological studies that found a relation between use of the drugs and admission to hospital for haemorrhage or perforation. SETTING: Hospital and community based case-control and cohort studies. MAIN OUTCOME MEASURES: (a) Estimated relative risks of gastrointestinal complications with use of individual drugs, exposure to ibuprofen being used as reference; (b) a ranking that best summarised the sequence of relative risks observed in the studies. RESULTS: 12 studies met the inclusion criteria. 11 provided comparative data on ibuprofen and other drugs. Ibuprofen ranked lowest or equal lowest for risk in 10 of the 11 studies. Pooled relative risks calculated with exposure to ibuprofen used as reference were all significantly greater than 1.0 (interval of point estimates 1.6 to 9.2). Overall, ibuprofen was associated with the lowest relative risk, followed by diclofenac. Azapropazone, tolmetin, ketoprofen, and piroxicam ranked highest for risk and indomethacin, naproxen, sulindac, and aspirin occupied intermediate positions. Higher doses of ibuprofen were associated with relative risks similar to those with naproxen and indomethacin. CONCLUSIONS: The low risk of serious gastrointestinal complications with ibuprofen seems to be attributable mainly to the low doses of the drug used in clinical practice. In higher doses ibuprofen is associated with a similar risk to other non-steroidal anti-inflammatory drugs. Use of low risk drugs in low dosage as first line treatment would substantially reduce the morbidity and mortality due to serious gastrointestinal toxicity from these drugs.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1996

Reproducibility of data collected by patient interview.

This study examined the reproducibility of data, not generally considered at risk for poor patient recall, obtained on two separate occasions. Our study used data collected for a register of heart attacks in the Lower Hunter Region of New South Wales, and included 1675 patients who were registered at least twice. Reporting inconsistencies between occasions were assessed for eight data items. We found that the sex of five patients had been recorded differently on the two occasions. Among patients interviewed on both occasions, between 0.5 per cent and 2.0 per cent of patients had inconsistent reports for marital status, country of birth, smoking status and height, 2.7 per cent for date of birth, 13 per cent for education level and between 1.6 per cent and 9.6 per cent for the history of various medical conditions. Patients not from an English-speaking background, over 60 years of age or without tertiary education tended to have higher rates of inconsistent reporting. Time between occasions, marital status and sex were not associated with increased rates of inconsistent reporting. We concluded that apparently straightforward data items, such as date of birth and education level, were not perfectly reproducible when obtained by patient interview on separate occasions. Our results provide a starting point for sensitivity analysis in other studies if the potential inaccuracies in reporting of such data should be of concern.

Data Collection↗
PubMed1996

International labor migration of Asian women: distinctive characteristics and policy concerns.

"The feminization of women in international labor migration has been most pronounced in the case of Asia, with women moving in their own right as economic migrants and faced with regulatory and social constraints, gender discrimination and exploitation in countries of origin and destination. Asian countries, both sending and receiving, have been experimenting with gender-sensitive migration policies and programs. This paper describes the characteristics of Asian female labor migration, examines policy dimensions and suggests action to bridge the gaps between policy dimensions and implementation."

Asia↗
PubMed1996

The migration transition in Malaysia.

"Exploring the unique experience of migration transition in Malaysia, this paper identifies the turning points in relation to the level and nature of economic and labor market developments in Malaysia. Examining the development dynamics that mark the passage from exporting labor to depending on foreign labor, the paper concludes that such dynamics are influenced not only by economic but also sociocultural, demographic and policy factors. Several lessons from the Malaysian experience are drawn at the end to be utilized by other countries that still have to reach the turning points of the migration transition."

Asia↗
PubMed1994

The movement of people in Asia: internal, intra-regional and international migration.

"The comprehensive overview of Asian-Pacific migration summarizes early population movements during the colonial period and describes the major types of contemporary Asian population movements: (1) environmental refugees, (2) political refugees, (3) internal population movements, (4) contract labor migration, (5) migration of permanent settlers, (6) business related movements and tourism. Projections of net international migration are given. Population growth, employment absorption and emigration pressures are likely to contribute to a large mobility potential for Asia, with significant implications for Australia."

Asia↗
PubMed1993

A self-administered quality-of-life questionnaire after acute myocardial infarction.

A slightly modified version of the Quality-of-Life after Myocardial Infarction (QLMI) questionnaire developed by Oldridge and colleagues was applied in a self-administered mode to patients with suspected acute myocardial infarction (AMI) in a randomized controlled trial of secondary prevention. Acceptability of the questionnaire was good, with 93% of responders answering all items. Factor analysis suggested three quality-of-life (QL) dimensions which we called "emotional", "physical" and "social". These differed somewhat from the dimensions proposed by Oldridge and colleagues. However, a sensitivity analysis showed relative invariance of results to weighting schemes. Scores on our three dimensions were responsive to differences between the treatment groups, and demonstrated construct validity based on associations between the measured QL and variables expected to affect QL. We conclude that the QLMI questionnaire has good potential as an instrument for assessing QL in post-AMI patients and that it can be successfully self-administered.

Factor Analysis, Statistical↗
PubMed1992

Estimating the ventilation-perfusion distribution: an ill-posed integral equation problem.

The distribution of ventilation-perfusion ratio over the lung is a useful indicator of the efficiency of lung function. Information about this distribution can be obtained by observing the retention in blood of inert gases passed through the lung. These retentions are related to the ventilation-perfusion distribution through an ill-posed integral equation. An unusual feature of this problem of estimating the ventilation-perfusion distribution is the small amount of data available; typically there are just six data points, as only six gases are used in the experiment. A nonparametric smoothing method is compared to a simpler method that models the distribution as a histogram with five classes. Results from the smoothing method are found to be very unstable. In contrast, the simpler method gives stable solutions with parameters that are physiologically meaningful. It is concluded that while such smoothing methods may be useful for solving some ill-posed integral equation problems, the simpler method is preferable when data are scarce.

Animals↗
PubMed1992

Estimating compliance to study medication from serum drug levels: application to an AIDS clinical trial of zidovudine.

This paper examines the use of serum drug levels to assess compliance to study medication in a clinical trial. We discuss problems of false-positivity, false-negativity, and bias that arise because of experimental errors in the drug assays, pharmacokinetic variations of the drug, and differential dosing levels. Basic concepts in probability are applied to derive a simple model that quantifies these problems. This model is used to obtain an estimate of compliance rate that corrects for these problems. However, derivation of this estimate requires additional information about false-positive and false-negative rates of the assay as well as some knowledge of the pharmacokinetic properties of the drug. We illustrate the evaluation of such a compliance estimate in the setting of an AIDS clinical trial of zidovudine (ZDV), in which some accessory data are available on the properties of ZDV serum assays and on the pharmacokinetic behavior of ZDV. We also describe a method that uses the accessory data to provide the additional information needed for computing the compliance estimate.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Drug level monitoring in a double-blind multicenter trial: false-positive zidovudine measurements in AIDS clinical trials group protocol 019.

Twenty-three different laboratories using four different assay methods reported zidovudine (ZDV; azidothymidine) measurements in a double-blind trial of ZDV for asymptomatic human immunodeficiency virus-infected patients (AIDS Clinical Trials Group Protocol 019). The risk of false-positive ZDV measurements was defined with coded specimens containing no ZDV in a quality control testing program. This testing identified six problem laboratories which reported ZDV levels of greater than or equal to 100 ng/ml for specimens with no ZDV; all of these laboratories used high-performance liquid chromatography. These six laboratories reported a disproportionately high fraction of positive assays for subjects randomized to the placebo group (31% for these 6 laboratories versus 4% for the other 17 laboratories; P less than 0.0001). The high number of false-positive ZDV results reported by these six laboratories suggested that many of the positive results that they reported for patient specimens were also false-positive results. This hypothesis was examined by retesting specimens from patients in the placebo group that had been reported as positive by these laboratories. Ninety percent (19 of 21) of these specimens were negative on retesting at the reference laboratory. These results confirm the hypothesis; they demonstrate the need for quality control testing to avoid the misinterpretation of multicenter trials because of incorrect laboratory data.

Acquired Immunodeficiency Syndrome↗