Trends in coronary heart disease mortality and morbidity in Auckland, New Zealand, 1974-1986

Impact of smoking reduction on coronary heart disease mortality trends during 1981-2000 in England and Wales

Objective

To explore how much of the coronary heart disease (CHD) mortality fall in England and Wales can be attributed to changes in smoking prevalence.

Methods

A previously validated cell-based IMPACT CHD mortality model was used to estimate the deaths prevented or postponed by changes in population smoking prevalence in England and Wales between 1981 and 2000. CHD mortality statistics and population trends in smoking were obtained from routine data sources.

Results

In England and Wales between 1981 and 2000, smoking prevalence in adults aged 25–84 decreased from 43% to 28% in men and from 35% to 24% in women. In men, most of the decrease occurred in those aged over 55. Smoking prevalence changed little in older women. An estimated 29,460 deaths were prevented or postponed (DPP) by this population reduction in smoking prevalence. Most of this benefit was seen in men (86% of the DPPs versus 14% in women).

Conclusion

Large declines in smoking prevalence accounted for 29,460 fewer CHD deaths in England and Wales in 2000 compared with 1981. This emphasises the importance of a national strategy with comprehensive tobacco control programmes to further reduce smoking.

Explanation for the decline in coronary heart disease mortality rates in Auckland, New Zealand, between 1982 and 1993

BACKGROUND

We sought to determine how much of the recent, substantial fall in coronary heart disease (CHD) mortality rates in New Zealand can be attributed to "evidence-based" medical and surgical treatments and how much can be attributed to cardiovascular risk factor reductions.

METHODS AND RESULTS

A cell-based mortality model was developed and refined. This model combined (1) the published effectiveness of cardiological treatments and risk factor reductions with (2) data on all medical and surgical treatments administered to all CHD patients and (3) trends in population cardiovascular risk factors (principally smoking, cholesterol, and hypertension) from 1982 to 1993 in Auckland, New Zealand (population 996 000). Between 1982 and 1993, CHD mortality rates fell by 23.6%, with 671 fewer CHD deaths than expected from baseline mortality rates in 1982. Forty-six percent of this fall was attributed to treatments (acute myocardial infarction 12%, secondary prevention 12%, hypertension 7%, heart failure 6%, and angina 9%), and 54% was attributed to risk factor reductions (smoking 30%, cholesterol 12%, population blood pressure 8%, and other, unidentified factors 4%). These proportions remained relatively consistent after a robust sensitivity analysis.

CONCLUSIONS

Approximately half the CHD mortality rate fall in Auckland, New Zealand, was attributed to medical therapies, and approximately half was attributed to reductions in major risk factors. These findings emphasize the importance of a comprehensive strategy that maximizes the population coverage of effective treatments and actively promotes a prevention program, particularly for smoking, diet, and blood pressure reduction.

Trends in coronary heart disease in two Belgian areas: results from the MONICA Ghent-Charleroi Study

SETTING

As part of the WHO-MONICA study, acute coronary events have been registered from 1983 until 1992 in the general population aged 25-69 years in two Belgian cities--Ghent in the northern Dutch speaking part of Belgium and Charleroi in the southern French speaking part. Registration of events was done according to an international standard protocol.

OBJECTIVE

To study trends in total, fatal and non-fatal event rates and trends in case fatality rates in these two cities.

MAIN RESULTS

Incidence of CHD was on average 50% higher in Charleroi compared with Ghent in both men and women (attack rate ratio Charleroi/Ghent was 1.5 in both sexes). In both men and women, diverging trends were observed between the two cities for total and non-fatal event rates, while parallel declining trends were observed in fatal event rates and in case fatality rates. In both sexes, total attack rates showed a significant decrease in Ghent and a significant increase in Charleroi. Also in the two sexes, attack rates of non-fatal events increased significantly in Charleroi and remained stable in Ghent. Attack rates of fatal events decreased significantly in men and women in Ghent and in men in Charleroi. Both "total" and "in hospital" case fatality rates declined significantly in both sexes in the two cities.

CONCLUSIONS

Important differences in coronary heart disease (CHD) incidence and CHD trends between Ghent and Charleroi were observed. These differences and trends are interpreted in the context of existing and still growing differences in the overall socioeconomic situation between the north and the south of the country. On the other hand, the efficacy of medical treatment of CHD is comparable in the two regions, as reflected by similar figures and trends for case fatality rates.

Inequalities in the transition of ischaemic heart disease mortality in New South Wales, Australia, 1969-1994

This paper examines changes in ischaemic heart disease mortality in New South Wales between 1969 and 1994, with particular reference to the 1969-1973, 1979-1983, 1985-1989 and 1990-1994 periods. Using death certificate data and unit list mortality files, and considering occupational differentials among males, and marital status and regional and intra-metropolitan variations among males and females, the question whether changes in differentials in mortality from heart disease occurred during this mortality transition is asked. Mortality from ischaemic heart disease declined in all marital status and occupational status groups, and in all geographical areas, but it declined more slowly among never married and divorced males, among manual workers, and in lower income areas. Whereas ischaemic heart disease mortality was lower in most rural areas than in metropolitan Sydney at the beginning of the period, in the 1990s it was significantly more elevated in inland small towns and rural areas than in the metropolis. Differentials increased over time, more especially with males.

[Gompertzian analysis of ischemic cardiopathy mortality in Spain, 1951-1992]

INTRODUCTION AND OBJECTIVES

In Spain ischemic heart disease mortality was increasing prior to 1975 and has decreased since 1975. This trend is common to both genders. The goal of this paper is to separate the genetic, environmental and competitive risk factors influencing this evolution.

METHODS

The Gompertz function was adjusted cross-sectionally to age-specific mortality due to ischemic heart disease for each year from 1951 to 1992. The Gompertzian longitudinal analysis was applied to the coefficients obtained to estimate the effect due to environmental and competitive factors.

RESULTS

Ischemic heart disease in Spain is a Gompertzian disease with an intersection point at 67 years for men and 40 years for women. Environmental factors were increasing before 1975 and have decreased since then. However, the competitive factors decreased in men since 1980 and in women since 1951 on.

CONCLUSION

The evolution of risk factors (smoking, hypercholesterolemia and hypertension) is responsible for the major proportion of ischemic disease mortality changes. Treatment of instaured ischemic disease has a low influence.

[Validation of "myocardial infarction" as cause of death on death certificates in Barquisimeto, Lara state, Venezuela]

Death rates due to Ischemic Heart Disease (IHD) are widely used to assess regional and national cardiovascular health status. However, their validity is questionable, essentially because they are based on death certificates (DCs). The present study was conducted in the Greater Metropolitan Area of Barquisimeto (Lara State, Venezuela), from June 1991 to July 1992. The purpose was to establish the validity of the diagnosis of myocardial infarction in DCs of intrahospital deaths. Efforts were made to locate all clinical charts and any other relevant information. To validate the diagnosis of MI in the DC we used the MONICA project criteria. During the study period a total of 247 eligible DCs were recorded. Sufficient clinical information was located for 136 cases (55%). The results were as follows: definite MI - 62 cases (45.6%); probable MI - 31 cases (22.8%); and non MI - 43 cases (31.6%). These results may indicate an overestimation of MI death rates of about 32% [95% Confidence Interval = 23.8% - 39.4%]. Since these data are from a region with an organized cardiovascular health system, it is expected that the overestimation for the rest of the country may be even higher. Thus, in order to enhance quality and accuracy of DCs, it is necessary to develop a system to improve adherence to existing norms for filling out and processing such forms.

Decline of coronary heart disease mortality in Finland during 1983 to 1992: roles of incidence, recurrence, and case-fatality. The FINMONICA MI Register Study

BACKGROUND

The rate of coronary heart disease (CHD) mortality in eastern Finland has been the highest in the world. The official mortality statistics suggest, however, that is has declined by 60% during the past 20 years. The aim of the present study was to examine the contributions of incidence, recurrence, and case fatality of coronary events to the trends in CHD mortality in three areas of Finland.

METHODS AND RESULTS

Population-based myocardial infarction registers have been operating in the provinces of North Karelia and Kuopio in eastern Finland and the Turku/Loimaa area in southwestern Finland from 1983 to 1992. During this 10-year period, each suspected coronary event in persons 35 to 64 years of age was evaluated for registration. Of these, 13,566 fulfilled the criteria of myocardial infarction or coronary death. Almost one fourth (22.4%) of the coronary events were sudden, out-of-hospital deaths. Among men, the average change in mortality was -7.1% per year (95% confidence interval, -8.4% to -5.8%) in North Karelia, -5.0% per year (-7.0% to -3.0%) in Kuopio, and -4.9% per year (-8.2% to -1.6%) in Turku/Loimaa. Among women, the corresponding changes were -5.6% (-11.1% to -0.1%), -4.4% (-8.1% to -0.7%), and -8.1% (-13.0% to -3.2%). In eastern Finland, the decline in CHD mortality was due to a decline in recurrent coronary events but also in the incidence of first coronary events, whereas in southwestern Finland, the decline in case-fatality rate had the major role.

CONCLUSIONS

The decline in CHD mortality rate in Finland appears to be the result of a successful combination of primary and secondary prevention measures and improvements in acute coronary care.

Sex differences in case fatality before and after admission to hospital after acute cardiac events: analysis of community based coronary heart disease register

OBJECTIVE

To determine whether the reported higher case fatality in hospital after an acute cardiac event in women can be explained by sex differences in mortality before admission and in baseline risk factors.

DESIGN

Analyses of data from a community based coronary heart disease register.

SETTING

Auckland region, New Zealand.

SUBJECTS

5106 patients aged 25-64 years with an acute cardiac event leading to coronary death or definite myocardial infarction within 28 days of onset, occurring between 1986 and 1992.

MAIN OUTCOME MEASURES

Case fatality before admission, 28 day case fatality for patients in hospital, and total case fatality after an acute cardiac event.

RESULTS

Despite a more unfavourable risk profile women tended to have lower case fatality before admission than men (crude odds ratio 0.88; 95% confidence interval 0.77 to 1.02). Adjustment for age, living arrangements, smoking, medical history, and treatment increased the effect of sex (0.72; 0.60 to 0.86). After admission to hospital, women had a higher case fatality than men (1.76; 1.43 to 2.17), but after adjustment for confounders this was reduced to 1.18 (0.89 to 1.58). Total case fatality 28 days after an acute cardiac event showed no significant difference between men and women (0.85; 0.70 to 1.02)

CONCLUSIONS

The higher case fatality after an acute cardiac event in women admitted to hospital is largely explained by differences in living status, history, and medical treatment and is balanced by a lower case fatality before admission.

Measuring outcomes: one month survival after acute myocardial infarction in Scotland

OBJECTIVE

To examine 30 day survival after acute myocardial infarction as an outcome indicator, and explore the effects of adjusting for available prognostic factors such as age, sex, co-morbidity, deprivation, and deaths outside hospital.

DESIGN

Cohort study.

SETTING

The Scottish Record Linkage System was analysed. This national data-base links inpatient data to death certificate information for a population of 5.1 million.

SUBJECTS

All 40,371 admissions to hospital with a principal diagnosis of acute myocardial infarction, plus all 18,452 deaths outside hospital with a principal cause of death registered as acute myocardial infarction (ICD9 code 410) during 1988-1991.

MAIN OUTCOME MEASURES

The outcome event was death from any cause, within hospital or elsewhere, within 30 days of admission.

RESULTS

During 1988-1991, 30 day survival after acute myocardial infarction was 77% in 40,371 hospital admissions, but only 53% when 18,452 acute myocardial infarction deaths in the community were included (a population-based outcome indicator with many advantages). Using logistic regression at an individual patient level, the odds of dying within 30 days effectively doubled for each decade of age (odds ratio compared with patients aged under 55: 2.3 aged 55-64, 4.4 aged 65-74, 8.2 aged 75-84, 12.0 aged 85 plus); were marginally higher in females than in males (odds ratio 1.07); were almost doubled in patients with a history of previous infarction, coronary heart disease, or other heart disease, and were also significantly increased in patients with circulatory disease, respiratory disease, neoplasm, or diabetes. Socioeconomic deprivation had no significant effect. Marked variations in survival between different hospitals and health board areas persisted, even after adjusting for the above prognostic factors.

CONCLUSION

One month survival after acute myocardial infarction could be a useful means of measuring outcome of hospital care. There was important geographical variation in one month survival. These differences could be accounted for by variations in referral, admission, diagnosis, definition, and coding. These variables merit further research and local clinical audit before one month survival after acute myocardial infarction can be reliably used for detecting differences in quality of care. In addition, it would be essential to take account of infarct severity.

A population-based assessment of the use and effectiveness of thrombolytic therapy. The Corpus Christi Heart Project

Little is known regarding the use and effectiveness of thrombolytic therapy in community settings, especially regarding the receipt of therapy by Mexican Americans. Thus, we examined the factors associated with receipt of thrombolysis and the survival experience of recipients and nonrecipients in the Corpus Christi Heart Project. The Corpus Christi Heart Project is a population-based surveillance program for hospitalized myocardial infarction among Mexican-American and non-Hispanic white women and men residing in Corpus Christi, Texas. Multivariate regression analyses were used to identify factors associated with receipt of thrombolytic therapy and to assess the association between receipt of thrombolytic therapy and mortality. During a 2-year period, 1199 patients hospitalized for myocardial infarction were identified; 159 (13.3%) received thrombolysis. Among "ideal" candidates for thrombolytic therapy, 74 (35.1%) of 211 received such therapy. Women were less likely to receive thrombolysis than men, and Mexican Americans were less likely to received thrombolysis than non-Hispanic whites. Patients for whom there was a delay of more than 4 hours between onset of symptoms and arrival at the hospital were also less likely to receive thrombolysis. Recipients of thrombolytic therapy experienced lower mortality over 56 months following myocardial infarction than did nonrecipients (20.5 versus 33.2%, P < 0.01). Use of thrombolytic therapy was less frequent among women and Mexican Americans than among men and non-Hispanic whites, and was limited by delay between onset of symptoms and arrival at the hospital.(ABSTRACT TRUNCATED AT 250 WORDS)

Trends in ischaemic heart disease in the Hunter Region of New South Wales 1985-1989

OBJECTIVE

To find out whether trends in rates of non-fatal myocardial infarction (MI) parallel trends in rates of coronary death.

DESIGN

A population-based observational study involving continuous surveillance of all suspected heart attacks or coronary deaths from 1985 to 1989.

STUDY POPULATION

Residents of the Hunter Region of New South Wales aged under 70 years.

MAIN OUTCOME MEASURES

Rates of non-fatal definite or possible MI or fatal MI or coronary death, as defined by the diagnostic criteria of the WHO MONICA Project.

RESULTS

For men, mortality rates declined by an average of 16.2 per 100,000 per year (95% confidence interval [CI]: -23.8, -8.7); rates of non-fatal definite MI declined by 16.2 per 100,000 (95% CI: -27.8, -4.6); rates of non-fatal possible MI increased initially and then stabilised. For women smaller changes occurred in the same directions.

CONCLUSION

In this population trends in rates for non-fatal definite MI paralleled the declines in mortality rates. Rates for less severe non-fatal possible MI did not follow this pattern, perhaps reflecting increased medical attention to chest pain.