Estimation of contribution of changes in classic risk factors to trends in coronary-event rates across the WHO MONICA Project populations

Background From the mid-1980s to mid-1990s, the WHO MONICA Project monitored coronary events and classic risk factors for coronary heart disease (CHD) in 38 populations from 21 countries. We assessed the extent to which changes in these risk factors explain the variation in the trends in coronary-event rates across the populations. Methods In men and women aged 35-64 years, non-fatal myocardial infarction and coronary deaths were registered continuously to assess trends in rates of coronary events. We carried out population surveys to estimate trends in risk factors. Trends in event rates were regressed on trends in risk score and in individual risk factors. Findings Smoking rates decreased in most male populations but trends were mixed in women; mean blood pressures and cholesterol concentrations decreased, body-mass index increased, and overall risk scores and coronary-event rates decreased. The model of trends in 10-year coronary-event rates against risk scores and single risk factors showed a poor fit, but this was improved with a 4-year time lag for coronary events. The explanatory power of the analyses was limited by imprecision of the estimates and homogeneity of trends in the study populations. Interpretation Changes in the classic risk factors seem to partly explain the variation in population trends in CHD. Residual variance is attributable to difficulties in measurement and analysis, including time lag, and to factors that were not included, such as medical interventions. The results support prevention policies based on the classic risk factors but suggest potential for prevention beyond these.

Predictors of death and vascular events in the elderly - The Perth Community Stroke Study

Background and Purpose-The goal of the present study was to identify risk factors for vascular disease in the elderly. Methods-We conducted a prospective study of control subjects from a population-based study of stroke in Perth, Western Australia, that was completed in 1989 to 1990 and used record linkage and a survey of survivors to identify deaths and nonfatal vascular events. Data validated through reference to medical records were analyzed with the use of Cox proportional hazards models. Results-Follow-up for the 931 subjects was 88% complete. By June 24, 1994, 198 (24%) of the subjects had died (96 from vascular disease), and there had been 45 nonfatal strokes or myocardial infarctions. The hazard ratio for diabetes exceeded 2.0 for all end points, whereas the consumption of meat >4 times weekly was associated with a reduction in risk of less than or equal to 30%. In most models, female sex and consumption of alcohol were associated with reduced risks, whereas previous myocardial infarction was linked to an increase in risk. Conclusions-There are only limited associations between lifestyle and major vascular illness in old age. Effective health promotion activities in early and middle life may be the key to a longer and healthier old age.

Public health implications of new guidelines for lead in drinking water: a case study in an area with historically high water lead levels

Concern about the neurotoxicity of lead, particularly in infants and young children, has led to a revision of blood lead levels which are considered to involve an acceptable level of human exposure. Drinking water guidelines have also been reviewed in order to reduce this source of population exposure to lead. In the last 20 years, guidelines have been reduced from 100 to 50 to 10 mu g/litre. Lead in tap water used to be a major public health problem in Glasgow because of the high prevalence of houses with lead service pipes, the low pH of the public water supply and the resulting high levels of lead in water used for public consumption. Following two separate programmes of water treatment, involving the addition of lime and, a decade later, lime supplemented with orthophosphate, it is considered that maximal measures have been taken to reduce lead exposure by chemical treatment of the water supply. Any residual problem of public exposure would require large scale replacement of lead service pipes. In anticipation of the more stringent limits for lead in drinking water, we set out to measure current lead exposure From tap water in the population of Glasgow served by the Loch Katrine water supply. to compare the current situation with 12 years previously and to assess the public health implications of different limits. The study was based on mothers of young children since maternal blood lead concentrations and the domestic water that mothers use to prepare bottle feeds are the principal sources of foetal and infant lead exposure. An estimated 17% of mothers lived in households with tap water lead concentrations of 10 mu g/litre (the WHO guideline) or above in 1993 compared with 49% in 1981. Mean maternal blood lead concentrations fell by 69% in 12 years. For a given water lead concentration, maternal blood lead concentrations were 67% lower. The mean maternal blood lead concentration was 3.7 mu g/litre in the population at large, compared with 3.3 mu g/litre in households with negligible or absent tap water lead. Nevertheless, between 63% and 76% of cases of mothers with blood lead concentrations of 10 mu g/dl or above were attributable to tap water lead. The study found that maternal blood lead concentrations were well within limits currently considered safe for human health. About 15% of infants may be exposed via bottle feeds to tap water lead concentrations that exceed the WHO guideline of 10 mu g/litre. In the context of the health and social problems which affect the well-being and development of infants and children in Glasgow, however, current levels of lend exposure are considered to present a relatively minor health problem. (C) 2000 Elsevier Science Ltd. All rights reserved.

MDMA (Ecstasy) neurotoxicity: assessing and communicating the risks

MDMA (3,4-methylenedioxymethamphetamine) is an amphetamine analogue that produces euphoric and stimulant effects and a feeling of closeness towards others.1 and 2 For more than a decade, MDMA (colloquially known as “Ecstasy” or “E”) has been widely used by young adults as a dance-party drug. The usual recreational oral dose is 1-2 tablets (each containing about 60-120 mg of MDMA) a standard oral dose of 0·75–4·00 mg per kg in 60–80 kg people. MDMA is typically used once fortnightly or less because tolerance to the effects of MDMA develops rapidly. More frequent use requires larger doses to achieve the desired effects, but this increases the prevalence of unpleasant side-effects.3 A number of deaths have occurred as a result of malignant hyperthermia or idiosyncractic reactions to the drug, but these have been rare.4 MDMA is perceived by many users to be a safe drug.1 Few report the craving associated with opiates or cocaine3 and most MDMA users are aware of only mild and transient disruptions of functioning.3 and 5 AC Parrott and J Lasky, Ecstasy (MDMA) effects upon mood and cognition: before, during and after a Saturday night dance, Psychopharmacology 139 (1998), pp. 261–268. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (174)5 The perceived safety of MDMA is at odds with animal evidence of MDMA neurotoxicity, an increasing prevalence of hazardous patterns of use among recreational MDMA users, and emerging evidence of neurotoxicity among heavier MDMA users.

Risk management for scuba diving operators on Australia's Great Barrier Reef

Australia's Great Barrier Reef is one of the world's most popular scuba diving destinations. Unfortunately, a series of recent diving injuries and deaths has tarnished the region's safety record. In particular, media attention surrounding the disappearance of American divers Thomas and Eileen Lonergan has focused attention on dive operators' legal responsibilities and the consequences of failing to discharge their duty of care to customers. This paper briefly examines the relevant Australian law for recreational diving operations, and reviews risk management strategies that may reduce or prevent the occurrence of future problems. (C) 2000 Elsevier Science Ltd. All rights reserved.

Cohort trends in youth suicide in Australia 1964-1997

Objective: This paper examines trends in the rate of suicide among young Australians aged 15-24 years from 1964 to 1997 and presents an age-period-cohort analysis of these trends. Method: Study design consisted of an age-period-cohort analysis of suicide mortality in Australian youth aged between 15 and 24 for the years 1964-1997 inclusive. Data sources were Australian Bureau of Statistics data on: numbers of deaths due to suicide by gender and age at death; and population at risk in each of eight birth cohorts (1940-1944, 1945-1949, 1950-1954, 1955-1959, 1960-1964, 1965-1969, 1970-1974, and 1975-1979). Main outcome measures were population rates of deaths among males and females in each birth cohort attributed to suicide in each year 1964-1997. Results: The rate of suicide deaths among Australian males aged 15-24 years increased from 8.7 per 100 000 in 1964 to 30.9 per 100 000 in 1997, with the rate among females changing little over the period, from 5.2 per 100 000 in 1964 to 7.1 per 100 000 in 1997. While the rate of deaths attributed to suicide increased over the birth cohorts, analyses revealed that these increases were largely due to period effects, with suicide twice as likely among those aged 15-24 years in 1985-1997 than between 1964 and 1969. Conclusions: The rate of youth suicide in Australia has increased since 1964, particularly among males. This increase can largely be attributed to period effects rather than to a cohort effect and has been paralleled by an increased rate of youth suicides internationally and by an increase in other psychosocial problems including psychiatric illness, criminal offending and substance use disorders.

Both beta(2)- and beta(1)-adrenergic receptors mediate hastened relaxation and phosphorylation of phospholamban and troponin I in ventricular myocardium of fallot infants, consistent with selective coupling of beta(2)-adrenergic receptors to G(s)-protein

Background-In adult human heart, both beta(1)- and beta(2)-adrenergic receptors mediate hastening of relaxation; however, it is unknown whether this also occurs in infant heart. We compared the effects of stimulation of beta(1)- and beta(2)-adrenergic receptors on relaxation and phosphorylation of phospholamban and troponin I in ventricle obtained from infants with tetralogy of Fallot. Methods and Results-Myocardium dissected from the right ventricular outflow tract of 27 infants (age range 2-1/2 to 35 months) with tetralogy of Fallot was set up to contract 60 times per minute. Selective stimulation of beta(1)-adrenergic receptors with (-)-norepinephrine (NE) and beta(2)-adrenergic receptors with (-)-epinephrine (EPI) evoked phosphorylation of phospholamban (at serine-16 and threonine-17) and troponin I and caused concentration-dependent increases in contractile force (-log EC50 [mol/L] NE 5.5+/-0.1, n=12; -EPI 5.6+/-0.1, n=13 patients), hastening of the time to reach peak force (-log EC50 [mol/L] NE 5.8+/--0.2; EPI 5.8+/-0.2) and 50% relaxation (-log EC50 [mol/L] NE 5.7+/-0.2: EPI 5.8+/-0.1), Ventricular membranes from Fallot infants, labeled with (-)-[I-125]-cyanopindolol, revealed a greater percentage of beta(1)- (71%) than beta(2)-adrenergic receptors (29%). Binding of (-)-epinephrine to beta(2)-receptors underwent greater GTP shifts than binding of (-)-norepinephrine to beta(1)-receptors. Conclusions-Despite their low density, beta(2)-adrenergic receptors are nearly as effective as beta(1)-adrenergic receptors of infant Fallot ventricle in enhancing contraction, relaxation, and phosphorylation of phospholamban and troponin I, consistent with selective coupling to G(s)-protein.

Impact on perinatal mortality of missed opportunities to treat maternal syphilis in rural South Africa: baseline results from a clinic randomized controlled trial

OBJECTIVE To demonstrate the impact on perinatal mortality of inadequate treatment for maternal syphilis despite adequate screening. METHOD In 12 clinics providing antenatal care in Hlabisa, South Africa 1783 pregnant women were screened for syphilis at their first antenatal visit between June and October 1998. Pregnancy outcome was determined among those with syphilis. RESULTS A total of 158 women were diagnosed with syphilis: prevalence 9% (95% CI 8-10%). Mean gestation at first antenatal visit was 24 weeks. Thirty women (19%) received no treatment and 96 (61%) received all three recommended doses of penicillin. Among those receiving at least one dose, mean delay to the first dose was 20 days. Among those fully treated mean delay to treatment completion was 34 days. Pregnancy outcome was known for 142 women (90%) and there were 17 perinatal deaths among 15 women (11%). Eleven of 43 women (26%) who received one or fewer doses of penicillin experienced ii perinatal death whilst only four of 99 women (4%) who received two or more doses of penicillin did so (P = 0.0001). Protection from perinatal death increased with the number of doses of penicillin: linear modelling suggests that one dose reduced the risk by 41%, two doses by 65% and three doses by 79%, compared with no doses. A dose-specific, categorical model confirmed reduction in risk by 79% for all three doses. CONCLUSION Despite effective screening, many pregnant women with syphilis remain inadequately treated, resulting in avoidable perinatal mortality. Delays in starting and finishing treatment, as well as incomplete treatment occur. Near-patient syphilis testing in the antenatal clinic with early treatment could improve treatment of syphilis and reduce perinatal mortality, and a randomized trial to test this is underway.

Lessons from a comprehensive clinical audit of users of psychiatric services who committed suicide

Objective: Characteristics of patients who committed suicide were examined to provide a picture of the treatment they received before death and to determine whether and how the suicides could have been pre vented by the service system. Methods: The unnatural-deaths register was matched to the psychiatric case register in the state of Victoria in Australia to identify suicides by people with a history of public-sector psychiatric service use who committed suicide between July 1, 1989, and June 30, 1994. Data on patient and treatment characteristics were examined by three experienced clinicians, who made judgments about whether the suicide could have been prevented had the service system responded differently. Quantitative and qualitative data were descriptively analyzed. Results: A total of 629 psychiatric patients who had committed suicide were identified. Seventy-two percent of the patients were male, 62 percent were under 40 years old, and 51 percent were unmarried. They had a range of disorders, with the most common being schizophrenia or schizoaffective disorder (36 percent). Sixty-seven percent had previously attempted suicide. A total of 311 patients (49 percent) received care within four weeks of death. Twenty percent of the suicides were considered preventable. Key factors associated with preventability were poor staff-patient relationships, incomplete assessments, poor assessment and treatment of depression and psychological problems, and poor continuity of care. Conclusions: Opportunities exist for the psychiatric service system to alter practices at several levels and thereby reduce patient suicides.

A model for predicting the future incidence of coronary heart disease within percentiles of coronary heart disease risk

Background We present a method (The CHD Prevention Model) for modelling the incidence of fatal and nonfatal coronary heart disease (CHD) within various CHD risk percentiles of an adult population. The model provides a relatively simple tool for lifetime risk prediction for subgroups within a population. It allows an estimation of the absolute primary CHD risk in different populations and will help identify subgroups of the adult population where primary CHD prevention is most appropriate and cost-effective. Methods The CHD risk distribution within the Australian population was modelled, based on the prevalence of CHD risk, individual estimates of integrated CHD risk, and current CHD mortality rates. Predicted incidence of first fatal and nonfatal myocardial infarction within CHD risk strata of the Australian population was determined. Results Approximately 25% of CHD deaths were predicted to occur amongst those in the top 10 percentiles of integrated CHD risk, regardless of age group or gender. It was found that while all causes survival did not differ markedly between percentiles of CHD risk before the ages of around 50-60, event-free survival began visibly to differ about 5 years earlier. Conclusions The CHD Prevention Model provides a means of predicting future CHD incidence amongst various strata of integrated CHD risk within an adult population. It has significant application both in individual risk counselling and in the identification of subgroups of the population where drug therapy to reduce CHD risk is most cost-effective. J Cardiovasc Risk 8:31-37 (C) 2001 Lippincott Williams & Wilkins.

Hair morphine concentrations of fatal heroin overdose cases and living heroin users

Aims To compare heroin and other opiate use of heroin overdose fatalities, current street heroin users and drug-free therapeutic community clients. Design Hair morphine concentrations that assess heroin use and other opiate use in the 2 months preceding interview or death were compared between heroin overdose fatalities diagnosed by forensic pathologists (fOD) (n = 42), current street heroin users (CU) (n = 100) and presumably abstinent heroin users in a drug-free therapeutic community (TC) (n = 50). Setting Sydney, Australia. Findings The mean age and gender breakdown of the three samples were 32.3 years, 83% male (FOD), 28.7 years, 58% male (CU) and 28.6 years, 60% male (TC). The median blood morphine concentration among the FOD cases was 0.35 mg/l, and 82% also had other drugs detected. There were large differences between the three groups in hair morphine concentrations, with the CU group (2.10 ng/mg) having concentration approximately four times that of the FOD group (0.53 ng/mg), which in turn had a concentration approximately six times that of the TC group (0.09 ng/mg). There were no significant differences between males and females in hair concentrations within any of the groups. Hair morphine concentrations were correlated significantly with blood morphine concentrations among FOD cases (r = 0.54), and self-reported heroin use among living participants (r = 0.57). Conclusions The results indicate that fatal cases had a lower degree of chronic opiate intake than the active street users, but they were not abstinent during this period.

How to do safe sternal reentry and the risk factors of redo cardiac surgery: A 21-year review with zero major cardiac injury

Objectives: Resternotomy is a common part of cardiac surgical practice. Associated with resternotomy are the risks of cardiac injury and catastrophic hemorrhage and the subsequent elevated morbidity and mortality in the operating room or during the postoperative period. The technique of direct vision resternotomy is safe and has fewer, if any, serious cardiac injuries. The technique, the reduced need for groin cannulation and the overall low operative mortality and morbidity are the focus of this restrospective analysis. Methods: The records of 495 patients undergoing 546 resternotomies over a 21-year period to January 2000 were reviewed. All consecutive reoperations by the one surgeon comprised patients over the age of 20 at first resternotomy: M:F 343:203, mean age 57 years (range 20 to 85, median age 60). The mean NYHA grade was 2.3 [with 67 patients (1), 273 (11),159 (111), 43 (IV), and 4 (V classification)] with elective reoperation in 94.6%. Cardiac injury was graded into five groups and the incidence and reasons for groin cannulation estimated. The morbidity and mortality as a result of the reoperation and resternotomy were assessed. Results: The hospital/30 day mortality was 2.9% (95% Cl: 1.6%-4.4%) (16 deaths) over the 21 years. First (481), second (53), and third (12) resternotomies produced 307 uncomplicated technical reopenings, 203 slower but uncomplicated procedures, 9 minor superficial cardiac lacerations, and no moderate or severe cardiac injuries. Direct vision resternotomy is crystalized into the principle that only adhesions that are visualized from below are divided and only sternal bone that is freed of adhesions is sewn. Groin exposure was never performed prophylactically for resternotomy. Fourteen patients (2.6%) had such cannulation for aortic dissection/aneurysm (9 patients), excessive sternal adherence of cardiac structures (3 patients), presurgery cardiac arrest (1 patient), and high aortic cannulation desired and not possible (1 patient). The average postop blood loss was 594 mL (95% CI:558-631) in the first 12 hours. The need to return to the operating room for control of excessive bleeding was 2% (11 patients). Blood transfusion was given in 65% of the resternotomy procedures over the 21 years (mean 854 mL 95% Cl 765-945 mL) and 41% over the last 5 years. Conclusions: The technique of direct vision resternotomy has been associated with zero moderate or major cardiac injury/catastrophic hemorrhage at reoperation. Few patients have required groin cannulation. In the postoperative period, there was acceptable blood loss, transfusion rates, reduced morbidity, and moderate low mortality for this potentially high risk group.

Mortality and recurrent cardiac events after coronary artery bypass graft: long term outcomes in a population study

Objective: To determine 30 day mortality, long term survival, and recurrent cardiac events after coronary artery bypass graft (CABG) in a population. Design: Follow up study of patients prospectively entered on to a cardiothoracic surgical database. Record linkages were used to obtain data on readmissions and deaths. Patients: 8910 patients undergoing isolated first CABG between 1980 and 1993 in Western Australia. Main outcome measures: 30 day and long term survival, readmission for cardiac event (acute myocardial infarction, unstable angina, percutaneous transluminal coronary angioplasty or reoperative CABG). Results: There were 3072 deaths to mid 1999. 30 day and long term survival were significantly better in patients treated in the first five years than during the following decade. The age of the patients, proportion of female patients, and number of grafts increased over time. An urgent procedure (odds ratio 3.3), older age (9% per year) and female sex (odds ratio 1.5) were associated with increased risk for 30 day mortality, while age (7% per year) and a recent myocardial infarction (odds ratio 1.16) influenced long term survival. Internal mammary artery grafts were followed by better short and long term survival, though there was an obvious selection bias in favour of younger male patients. Conclusions: This study shows worsening crude mortality at 30 days after CABG from the mid 1980s, associated with the inclusion of higher risk patients. Older age, an acute myocardial infarction in the year before surgery, and the use of sephenous vein grafts only were associated with poorer long term survival and greater risk of a recurrent cardiac event. Female sex predicted recurrent events but not long term survival.