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Biomedical subjects

K D Jamrozik

Publications and source records attributed to K D Jamrozik.

26 records · Page 2Linked to original sources

Mortality from coronary heart disease and incidence of acute myocardial infarction in Auckland, Newcastle and Perth.

OBJECTIVE: To confirm the existence of regional differences in coronary death rates in Australia and New Zealand and to determine whether or not these are associated with parallel differences in the incidence of acute myocardial infarction. DESIGN: Descriptive epidemiological study. SETTING: Community based study. SUBJECTS: Residents of Auckland, Newcastle and Perth aged 25-64 years admitted to hospital for acute myocardial infarction or dying from coronary heart disease between 1983 and 1987. MAIN OUTCOME MEASURES: Definite acute myocardial infarction or coronary death classified according to the criteria of the World Health Organization MONICA project. RESULTS: This study confirms the marked variation, evident from official statistics, in mortality rates from ischaemic heart disease between Newcastle (high), Auckland and Perth (low). A different pattern is observed for the incidence of acute myocardial infarction and there are also obvious differences between centres in the case fatality ratios for all acute coronary events combined. Newcastle has the highest rate for all coronary events, particularly in women. Auckland is characterised by substantially higher case fatality ratios compared with the two Australian cities. This is due especially to higher rates of coronary death outside hospital. Perth, which has the lowest mortality rates and case fatality ratios in both men and women, has rates for admission to hospital for acute myocardial infarction and all cases of ischaemic heart disease that are disproportionately high in relation to the corresponding mortality rates. CONCLUSION: The differences in case fatality ratios between these three centres are not readily explained by artefacts related to enumeration or classification. Rather, they are most likely related to differences in the natural history of ischaemic heart disease in the three populations. Differences in medical management may also contribute to the substantial variation in mortality rates.

Adult↗

Principles behind practice. 7. Case-control studies.

The case-control study is often a very simple, cheap and quick way to test the hypothesis that a particular factor causes a disease or that a particular treatment is helping patients who receive it. There also seems to be an inherent logic in comparing patients and well people to see how they differed in the past, or in comparing those who did and did not survive a certain illness to see how their treatment differed. Despite these appealing features, the case-control approach is subject to a number of pitfalls. These can usually be avoided by an appropriately designed study, and by careful collection and analysis of the data. Even so, the results of a case-control study are a lower order of evidence than those produced from a properly conducted randomised controlled trial.

Bias↗

The benefits of beta-blockade at the time of myocardial infarction.

Data from the World Health Organization Monitoring Trends and Determinants in Cardiovascular Disease (WHO MONICA) project, collected in Perth, are described. Patients taking a beta-blocker at the time of onset of myocardial infarction are a high-risk group, but univariate analysis of the data showed that the overall survival of patients on beta-blockers at 28 days was the same as for those not taking beta-blockers. A multiple logistic regression model analysis showed that the patients treated with beta-blockers had a survival advantage at 28 days, with a relative risk of death of 0.5. The mechanism of benefit is unclear. It does not appear to be an anti-arrhythmic effect, because beta-blockers did not affect survival in the first 24 h following a myocardial infarction, nor did they affect ventricular fibrillation. The effect may be due to a reduction in myocardial necrosis. Furthermore, an analysis of the incidence of coronary disease and type of drugs prescribed in Perth has indicated that beta-blockers may be contributing to a decrease in mortality due to coronary events.

Adrenergic beta-Antagonists↗

Reduced risk of death at 28 days in patients taking a beta blocker before admission to hospital with myocardial infarction.

OBJECTIVE: To see whether patients taking an oral beta blocker at the time of admission to hospital with myocardial infarction have a reduced risk of death at 28 days. DESIGN: Retrospective analysis of data collected on patients admitted over four years. SETTING: Community based study. PATIENTS: 2430 Consecutive patients living in the Perth statistical division admitted to hospital with myocardial infarction during 1984-7. MAIN OUTCOME MEASURE: Survival at 28 days among patients taking a beta blocker at onset of myocardial infarction. RESULTS: Patients were grouped into those who were and were not taking a beta blocker at the time of admission. Though patients taking a beta blocker were older and more likely to have a history of myocardial infarction, angina, or hypertension, the overall mortality at 28 days was similar in the two groups. A logistic regression model used to adjust for factors predictive of cardiac death at 28 days confirmed that patients taking a beta blocker at the time of admission had a significantly reduced risk of death (relative risk 0.50; 95% confidence interval 0.34 to 0.76). Though the incidence of fatal ventricular fibrillation was similar in the two groups, mean peak creatine kinase activity was significantly lower in the beta blocker group. CONCLUSIONS: These data support the value of long term use of beta blockers in patients at risk of myocardial infarction. They suggest that patients taking these agents before admission to hospital with myocardial infarction have a significant survival advantage at 28 days, which may be due to a reduction in infarct size.

Adrenergic beta-Antagonists↗

Underuse of beta-blockers following myocardial infarction: a tale of two cities.

AIMS: To measure factors associated with underuse of beta-blocker therapy after myocardial infarction (MI). METHODS: The Newcastle and Perth collaborating centres of the World Health Organization (WHO) MONICA project (to MONItor trends and determinants of Cardiovascular disease) systematically evaluated all patients admitted to hospital in their respective regions with possible MI. A total of 1766 patients in Newcastle and 4,503 patients in Perth, discharged from hospital after confirmed MI from 1985 to 1993, were studied. Rates of beta-blocker use before and after hospital discharge were evaluated and correlates of beta-blocker use determined. RESULTS: Beta-blocker use was similar in Newcastle and Perth before MI (21% of patients in each centre). During hospital admission, beta-blocker therapy was initiated nearly twice as frequently in Perth compared with Newcastle (66 vs 36%, respectively) and more patients were discharged from hospital on beta-blockers in Perth (68%) than in Newcastle (45%). The main factors associated with underuse of beta-blockers in multivariate analysis were geographical centre (odds ratio (OR) for Newcastle compared with Perth 0.3; 95% confidence interval (CI) 0.3-0.3), a history of previous MI (OR 0.6, 95% CI 0.5-0.7), admission to hospital in earlier years (OR 0.4, 95% CI 0.3-0.4 for years 1985-87 compared with years 1991-93), diabetes (OR 0.6, 95% CI 0.5-0.8) and the concomitant use of diuretics (OR 0.5, 95% CI 0.4-0.6) and calcium antagonists (OR 0.6, 95% CI 0.5-0.8). CONCLUSIONS: Underuse of beta-blockers after MI was strongly related to hospital prescribing patterns and not to community use of beta-blockers. Underuse occurred in patients with diabetes and in patients with left ventricular dysfunction, patients who stand to benefit most from beta-blocker use following MI.

Adrenergic beta-Antagonists↗

Eye injuries among pennant squash players and their attitudes towards protective eyewear.

A questionnaire survey on eye injuries and attitudes towards protective eyewear was conducted among 165 metropolitan pennant squash players; 163 (99%) valid responses were received. The incidence of eye injuries in the survey sample was found to be 17.5 per 100,000 playing hours with a significant proportion (26%) indicating that they had suffered at least one eye injury. Racquets were more common as the source of injury (61%) than squash balls. A large proportion of those injured consulted a doctor (63%) with approximately one-third (or 5% of the total survey sample) having been admitted to hospital for the injury. Only 8% of the sample used appropriate protective eyewear with an additional 2% believing their prescription lenses were a form of protection. The main reason given for using protective eyewear was previous injury to self or others (65% of cases). Doctors and media promotion rated poorly in causing players to use eyewear (6% for each). Most respondents believed eyewear to be of benefit, but fewer than half felt that eyewear should be made compulsory for all players. Only 6% of players said that they would give up the game if use of eyewear was made compulsory.

Attitude to Health↗