Lynette Lim

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 (τ2= 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.

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.

An improved questionnaire for assessing quality of life after acute myocardial infarction

This paper reports our experience with the use of an improved self-administered questionnaire for assessing quality of life (QOL) after acute myocardial infarction. The modified questionnaire significantly increased the proportion of patients able to answer all questions from 84%–92%. The additional questions in the improved questionnaire increased the total variance explained by the Emotional, Physical and Social QOL factors from 65.8%–66.5%. Internal consistency and construct validity were assessed and found to be high. Overall, we have found that this improved questionnaire is easy to administer and that it possesses desirable properties of validity and reliability.

Work and health in a contemporary society: demands, control, and insecurity

Objective: To examine independent associations of job strain (high demands and low control) and job insecurity with mental and physical health outcomes. Design: Cross sectional general population study conducted in 2000 using a self completed questionnaire. Setting: Two adjoining cities in south east Australia. Subjects: 1188 employed professionals, aged 40–44 years, 55% (n = 655) male. Main outcome measures: Depression, anxiety, physical, and self rated health (SRH). Results: Adverse job conditions were relatively prevalent as 23% of the sample reported high job strain, while 7.3% and 23% reported high and moderate job insecurity respectively. Associations between job conditions and health persisted after adjustment for gender, education, marital status, employment status, major life events, and negative affectivity (personality). When adjusted for job strain, high job insecurity was independently associated with a greater than threefold increase in odds for poor SRH, depression and anxiety (OR (95% confidence intervals) poor SRH: 3.72 (1.97 to 7.04) depression: 3.49 (1.90 to 6.41), anxiety: 3.29 (1.71 to 6.33)), and a twofold increase for physical health 2.19 (1.21 to 3.95). High job strain also showed significant independent associations with depression: 2.54 (1.34 to.4.75) and anxiety: 3.15 (1.48 to 6.70). Conclusion: In this relatively privileged socioeconomic group, insecure employment and high job strain showed independent, consistent, and strong associations with physical and mental health. These adverse job conditions are on the increase, particularly insecure employment, and the influence of these two work conditions are an important focus for future public health research and their prevalence and impact should be examined in other occupations.

Low maternal exposure to ultraviolet radiation in pregnancy, month of birth, and risk of multiple sclerosis in offspring: longitudinal analysis

Objectives To investigate the distribution of month of birth in people with multiple sclerosis in Australia. To use the large regional and seasonal variation in ambient ultraviolet radiation in Australia to explore the association between exposure to ultraviolet radiation during pregnancy and subsequent risk of multiple sclerosis in offspring. Design Data were gathered on birth month and year (1920-1950), sex, and state of birth for all patients surveyed in 1981 in Queensland, Western Australia, New South Wales (including Australian Capital Territory), South Australia, and Hobart (Tasmania). Population denominators were derived from the 1981 census and supplementary birth registration data. A variable for exposure to ambient ultraviolet radiation “at birth” was generated from monthly averages of daily total ambient ultraviolet radiation for each region. Negative binomial regression models were used to investigate exposure to ambient ultraviolet radiation at birth and at various intervals before birth. Setting Patient data from multiple sclerosis prevalence surveys carried out in 1981; 1981 Australian census (giving the total number of people born in Australia and still alive and living in Australia in 1981 by year of birth 1920-50); supplementary Australian birth registration data covering the same birth years by month and state. Participants 1524 patients with multiple sclerosis born in Australia 1920-50 from total population of 2 468 779. Main outcome measure Cumulative incidence rate of multiple sclerosis. Results There was a pattern of risk of multiple sclerosis with month of birth (adjusted incidence rate ratio 1.32, 95% confidence interval 1.10 to 1.58, P<0.01, for those born in November-December compared with those born in May-June). This pattern mirrored that previously reported in the northern hemisphere. Region of birth was related to risk. After adjustment for region of birth and other factors, there was an inverse association between ambient ultraviolet radiation in the first trimester and risk of multiple sclerosis (with ≥25 erythemal (skin reddening) dose units as reference (that is, adjusted incidence rate ratio=1.00), the rates were 1.54 (1.10 to 2.16) for 20-<25 units; 1.58 (1.12 to 2.22) for 15-<20 units; 1.65 (1.17 to 2.33) for 10-<15 units; 1.65 (1.18 to 2.29) for 5-<10 units; and 1.67 (1.18 to 2.37) for <5 units). After adjustment for this exposure during early pregnancy, there was no residual association between month of birth and multiple sclerosis. Conclusion Region of birth and low maternal exposure to ultraviolet radiation in the first trimester are independently associated with subsequent risk of multiple sclerosis in offspring in Australia.

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 incompletion rate.

The MacNew heart disease health-related quality of life instrument: Reference data for users

Objective: To report reference data for the heart-specific MacNew Heart Disease Health-Related Quality of Life instrument. Methods: One thousand five hundred and six patients with myocardial infarction (n = 346), heart failure (n = 201), and ischaemic heart disease (IHD, n = 959) were surveyed 4 months after hospital discharge. Quality of life scores were determined, stratified by diagnostic category, age and sex. Changes in scores from 4 to 8 months post-discharge were calculated for a subset of 830 patients, stratified by age and sex. Results: At 4 months there were no significant differences in scores between myocardial infarction and electively admitted IHD patients, however the scores of heart failure patients were significantly lower (indicating poorer quality of life) than those of patients with other diagnoses. There were few significant differences between age groups or sexes when comparing within diagnostic groups. Change from 4 to 8 months was not associated with diagnosis, age, or sex but was associated with events within the period (readmission or revascularisation). The change data suggest that a value of 0.5 may be a useful indicator of the minimal clinically important difference. Conclusions: These reference data will assist in sample size calculations and with comparison of results in other studies, and will be of use to researchers who are using or intending to use the MacNew instrument.

Job Strain, Job Insecurity, and Health: Rethinking the Relationship

Job strain (high demands and low control) is a widely used measure of work stress. The authors introduce a new way of looking at work stress by combining job strain with job insecurity, a combination increasingly prevalent in contemporary economies, using data from a cross-sectional survey (N = 1,188) of mid-aged Australian managers and professionals. Those reporting both strain and insecurity showed markedly higher odds for mental and physical health problems (depression: odds ratio [OR] 13.88, 95% confidence interval [CI] 5.67-34.01; anxiety: OR 12.88, CI 5.12-32.39; physical health problems: OR 3.97, CI 1.72-9.16; and poor self-rated health: OR 7.12, CI 2.81-18.01). Job strain and insecurity showed synergistic associations with health, and employees experiencing both could be at heightened health risk.

Thai SF-36 health survey: tests of data quality, scaling assumptions, reliability and validity in healthy men and women

BackgroundSince its translation to Thai in 2000, the SF-36 Health Survey has been used extensively in many different clinical settings in Thailand. Its popularity has increased despite the absence of published evidence that the translated instrument satisfies scoring assumptions, the psychometric properties required for valid interpretation of the SF-36 summated ratings scales. The purpose of this paper was to examine these properties and to report on the reliability and validity of the Thai SF-36 in a non-clinical general population.Methods1345 distance-education university students who live in all areas of Thailand completed a questionnaire comprising the Thai SF-36 (Version 1). Median age was 31 years. Psychometric tests recommended by the International Quality of Life Assessment Project were used.ResultsData quality was satisfactory: questionnaire completion rate was high (97.5%) and missing data rates were low (< 1.5% for all items). The ordering of item means within scales generally were clustered as hypothesized and scaling assumptions were satisfied. Known groups analysis showed good discriminant validity between subgroups of healthy persons with differing health states. However, some areas of concern were revealed. Possible translation problems of the Physical Functioning (PF) items were indicated by the comparatively low ceiling effects. High ceiling and floor effects were seen in both role functioning scales, possibly due to the dichotomous format of their response choices. The Social Functioning scale had a low reliability of 0.55, which may be due to cultural differences in the concept of social functioning. The Vitality scale correlated better with the Mental Health scale than with itself, possibly because a healthy mental state is central to the concept of vitality in Thailand.ConclusionThe summated ratings method can be used for scoring the Thai SF-36. The instrument was found to be reliable and valid for use in a general non-clinical population. Version 2 of the SF-36 could improve ceiling and floor effects in the role functioning scales. Further work is warranted to refine items that measure the concepts of social functioning, vitality and mental health to improve the reliability and discriminant validity of these scales.

The association between overall health, psychological distress, and occupational heat stress among a large national cohort of 40,913 Thai workers.

Background: Occupational heat stress is a well-known problem, particularly in tropical countries, affecting workers, health and well-being. There are very few recent studies that have reported on the effect of heat stress on mental health, or overall health in workers, although socioeconomic development and rapid urbanization in tropical developing countries like Thailand create working conditions in which heat stress is likely. Objective: This study is aimed at identifying the relationship between self-reported heat stress and psychological distress, and overall health status in Thai workers. Results: Show that 18% of our large national cohort (>40,000 subjects) often works under heat stress conditions and males are exposed to heat stress more often than females. Furthermore, working under heat stress conditions is associated with both worse overall health and psychological distress (adjusted odds ratios ranging from 1.49 to 1.84). Conclusions: This association between occupational heat stress and worse health needs more public health attention and further development on occupational health interventions as climate change increases Thailands temperatures.