Increasing incidence and mortality from myocardial infarction in Stockholm county

Time trends in the incidence of myocardial infarction among professional drivers in Stockholm 1977-96

AIMS

To investigate time trends in the incidence of first myocardial infarction (MI) among bus, taxi, and lorry drivers in Stockholm.

METHODS

In this population based case-control study, all first events of acute MI among men aged 40-69 in Stockholm County 1977-96 were identified using registers of hospital discharges and deaths. Controls were selected randomly from the general population. National censuses were used for information on occupational titles. A total of 20,364 cases and 136,342 controls were included in the study. Among these, 1183 cases and 6072 controls had worked as drivers.

RESULTS

During 1977-84 the MI incidence was higher in all three driver groups than among other manual workers. There was a decline in MI incidence among drivers as well as in the general population during the study period. The decline was greater among drivers than among other manual workers. During 1985-96 the relative risk remained increased compared to other manual workers among taxi and lorry drivers, but not among bus drivers.

CONCLUSIONS

Despite a reduced MI incidence for professional drivers in recent years, preventive measures to reduce the risk of MI in these occupational groups, and in particular among taxi and lorry drivers, continue to be of importance.

Are geographical differences and time trends in myocardial infarction incidence in Sweden real? Validity of hospital discharge diagnoses

In Sweden, acute myocardial infarction (AMI) incidence has been found to differ considerably between the neighboring counties of Stockholm and Gävleborg, with an increase in Stockholm during the 1970s. We estimated the AMI incidence in Stockholm in 1973 and in both areas in 1981. To determine if there were differences in the validity of hospital discharge diagnoses, random samples of AMI patients were examined for diagnostic criteria for AMI. In both genders, AMI incidence was higher in Gävleborg than in Stockholm (relative risk (RR) 1.34 for men and 1.21 for women) and increased in Stockholm from 1973 to 1981 (RR 1.21 for men and 1.29 for women). The proportion of patients fulfilling the diagnostic criteria for AMI was similar in both areas in 1981 but 10% less in Stockholm in 1981 than in 1973. These results suggest that differences in the validity of hospital discharge diagnoses cannot explain the geographical differences in AMI incidence, but that this may have contributed to the increasing incidence seen in Stockholm county.

Epidemiology of diaphyseal femoral fracture

The incidence of diaphyseal femoral fracture in adults, aged 20 years and older, was determined in Stockholm County using hospital admission rates. The validity of the data was investigated by a study of the medical records of a sample of 277 cases and also by determining the incidence in a subpopulation of 139 cases using an alternative method. The incidence decreased from age 20 to middle age after which it increased into old age. The age-related increase was more pronounced in women and in fractures caused by moderate trauma. From 1972 to 1981, the incidence of diaphyseal femoral fracture caused by moderate trauma increased annually by 10 per cent in women aged 75 years and older.

Psychosocial aspects of coronary heart disease

Attention is drawn to studies which throw doubt upon the importance of nutrition and smoking in the etiology of coronary heart disease (CHD). The main part of the review deals with psychosocial research in the field of CHD. A number of studies show that there is a clearcut association between life style, life events, social class, economic cycles, culture and CHD. The modern coronary epidemic is related to the economic boom which the US experienced during the 1940-60s and which followed a decade later in Western Europe. The later decline of CHD is related to the economic stagnation that took place in the US at the end of the 1960s. Obviously, risk factors must be seen in a cultural perspective, and the moderating effects of social support should be taken into account.

Trends in ischemic heart disease mortality in Italy, 1968-78

In Italy during the period 1968-78, female heart disease mortality decreased in all age groups up to age 79, with an average annual rate of decline in the 35-74 age-standardized rate of over 0.7 per cent. In males, age-specific death rates in some age groups were stable or increased moderately, but in middle-aged (50 to 59) males there was a consistent increase so that the rise in the 35-74 age standardized male death rate was approximately 1 per cent per year.

Hip fracture incidence in Stockholm 1972-1981

We studied the incidence of cervical and trochanteric hip fractures in Stockholm, Sweden from 1972 through 1981. The material, selected from a computerized medical information register, consisted of 11 812 cervical fractures and 8094 trochanteric fractures. The incidence did not change in the age group 50-74 years. In males 75 years of age and older, the incidence of both fracture types caused by moderate trauma increased annually by 5-6 per cent. In females 75 years and older, the incidence of trochanteric fractures caused by moderate trauma increased annually by 6 per cent, whereas the incidence of cervical fractures increased only marginally.

Changes in incidence and prognosis of ischaemic heart disease in Finland: a record linkage study of data on death certificates and hospital records for 1972 and 1981

The components of the decline in mortality from ischaemic heart disease in Finland were studied by analysing the changes in incidence and prognosis between 1972 and 1981. Using personal identification numbers, hospital discharge records and death certificates were linked for all men and women aged 40-64. During this period mortality decreased 15.9% in men and 23.5% in women, incidence 14.2% in men and 19.3% in women, being greatest among 40-49 year olds living in urban areas, and case fatality 7.3% in men and 10.3% in women, owing primarily to a decrease in patients dying of ischaemic heart disease without being admitted to hospital; survival was also better among patients admitted to hospital. Factors explaining these changes remain unknown because data on risk factors and factors influencing prognosis are limited and largely ecological.

Epidemiology of acute cerebrovascular disease before the age of 55 in the Stockholm County 1973-77: I. Incidence and mortality rates

The incidence and mortality rates of cerebrovascular disease (CVD) before age 55 were estimated for the Stockholm county between 1973 and 1977 using community based diagnosis and death statistics registers. Annual validation procedures concluded that less than 5% of hospitalized patients may have escaped registration. During the study period a diagnosis of CVD (initial stroke or TIA) was reported in 2,103 individuals, giving annual average crude incidence rates for stroke and TIA of 34 and 4 respectively per 100,000 inhabitants under age 55. Hemorrhagic lesions were reported in 45.4% of the cases, ischemic lesions in 33.1% and unclassified lesions in 21.5%. For all diagnostic categories a strong correlation to age is found, and for most categories the male:female ratio is high. The mortality rates are high for hemorrhagic lesions and low for ischemic and unclassified lesions. Incidence rates are higher than in Uppsala and Gothenburg, Sweden, but lower than in North Karelia, Finland. Mortality rates are similar to those reported by most other investigators.

Decline in coronary heart disease mortality. Old questions and new facts

By 1979, mortality rates for coronary heart disease had declined for 14 consecutive years in the United States. Preliminary data indicate a continued decline. This review of reports published in the last five years documents the consistency of most data with the following hypotheses: (1) Reductions in population levels of hypertension and cigarette smoking have contributed to the decline in mortality from coronary heart disease. (2) Improved medical care for acute myocardial infarction has also contributed to the decline. Data are lacking to specify the contributions of changes in other risk factors, emergency medical services, medical care of chronic coronary heart disease, or other changes in the physical and social environment. Long-term, simultaneous surveillance of mortality, morbidity, medical care, and risk factors should be supported in five to 10 centers around the United States.