Recent morbidity trends in myocardial infarction in Japan: investigation of death certificates and the survival rates at coronary care units

Alkaline phosphatase and risk of stroke among Japanese: the Circulatory Risk in Communities Study (CIRCS)

Although serum alkaline phosphatase (ALP) levels have been associated with mortality from all-cause and from either ischemic or hemorrhagic stroke, no study has been published of the associations between ALP and the incidence of stroke. We therefore examined the associations of ALP with risk of stroke among Japanese, stratified by drinking status because ALP is known as an enzyme affected by alcohol consumption. We conducted a prospective cohort study of 10,754 Japanese subjects (4098 men and 6656 women) aged 40-69 years and living in 4 communities under systematic surveillance for stroke incidence. During the 16-year follow-up, we documented 264 strokes (164 ischemic strokes and 69 hemorrhagic strokes) for men and 225 strokes (118 ischemic strokes and 89 hemorrhagic strokes) for women. There was a U-shaped association between ALP level and stroke incidence in both men and women, which was confined primarily to nondrinkers. For nondrinkers, higher ALP levels were associated with an elevated risk of ischemic stroke for men and of hemorrhagic stroke for women, whereas lower ALP levels were associated with elevated risks of ischemic and hemorrhagic strokes in both men and women. Our data indicate that not only higher, but also lower, serum ALP level may be a predictor for the risk of stroke in nondrinking men and women.

Chronic kidney disease and drinking status in relation to risks of stroke and its subtypes: the Circulatory Risk in Communities Study (CIRCS)

BACKGROUND AND PURPOSE

Several epidemiological studies have established an association between chronic kidney disease (CKD), based on estimated glomerular filtration rate (GFR), and risk of stroke. However, sex-specific evidence for the relationship between CKD and risk of stroke and its subtypes is still limited.

METHODS

We conducted a prospective cohort study of 12 222 Japanese men and women age 40 to 69 years living in 4 communities under systematic surveillance of stroke incidence to determine the relationship between CKD and risk of stroke and its subtypes.

RESULTS

During the 17-year follow-up, there were 566 strokes (327 ischemic and 186 hemorrhagic strokes). GFR was inversely associated with age- and community-adjusted risk of total stroke for both men and women. Compared with the reference group without CKD (GFR ≥60 mL/min per 1.73m(2)), the adjusted risks of total stroke for subjects with CKD (GFR <60 mL/min per 1.73m(2)) were 1.63 (1.22-2.17) for men and 1.51 (1.13-2.02) for women. Excess risk of stroke associated with CKD was identified primarily for hemorrhagic stroke among men and for ischemic stroke among women. After adjustment for traditional cardiovascular risk factors, associations remained statistically significant. When stratified by drinking status, excess risk of hemorrhagic stroke with CKD was confined to drinkers; adjusted risks were 4.18 (2.31-7.57) for men and 7.00 (1.92-25.56) for women.

CONCLUSIONS

CKD was associated with increased risk of hemorrhagic stroke for men, and of ischemic stroke for women. This sex difference may partly be explained by the difference in prevalence of drinkers between men and women.

A large-scale prospective cohort study on the current status of therapeutic modalities for acute myocardial infarction in Japan: rationale and initial results of the HIJAMI Registry

BACKGROUND

In Western countries, several multicenter collaborative studies on acute myocardial infarction (AMI) have provided much information about this disease. In Japan, on the other hand, there have been few cohort studies in which a sufficient number of Japanese patients with AMI were registered during a short period. This fact explains the absence of a database from which strategies for treating Japanese patients with AMI could be established. The purpose of this study was to build a comprehensive database on Japanese patients with AMI to elucidate their characteristics.

METHODS

Between January 1999 and June 2001, we consecutively registered all patients with AMI who were admitted to 17 participating medical institutions, including The Heart Institute of Japan, Cardiology (HIJC), Tokyo Women's Medical University. A standardized case report form was used to register all the patients.

RESULTS

A total of 3,021 consecutive patients was registered (2,136 men, 70.7%; 885 women, 29.3%) with a median age of 69 years [59, 77]. Among the patients, there were 851 elderly individuals (28.2%) > or = 76 years and 1102 patients with diabetes (36.5%). On index electrocardiogram, ST-elevation myocardial infarction was observed in 2,392 patients (79.2%). Within 24 hours after the onset of AMI, coronary angiography was conducted for 2,177 patients (72.1%). Primary percutaneous coronary intervention and coronary thrombolysis were conducted for 1,755 (58.1%) and 491 patients (16.3%), respectively, and percutaneous coronary intervention or coronary artery bypass grafting was additionally carried out in 303 patients. By the time of discharge, coronary angiography and coronary artery bypass grafting were performed in 2,659 (88.0%) and 137 patients (4.5%), respectively. During initial hospitalization, 285 patients died and the overall inhospital mortality rate was 9.4%. During hospitalization, cardiogenic shock and cardiac rupture were observed in 6.1% and 2.8% of the patients, respectively. The inhospital mortality rate is still high in patients with AMI with such mechanical complications and in elderly patients.

CONCLUSION

In our prospective cohort, we showed that Japanese patients with AMI could be characterized as (1) having a disease severity comparable with values observed in Western populations and (2) receiving early reperfusion therapy by PCI, which was used widely and safely, but nevertheless (3) exhibiting a high inhospital mortality rate. Our data indicate that further improvements in therapy for AMI in elderly patients and for AMI with mechanical complications are essential in Japan.

Trends in the incidence of coronary heart disease and stroke and the prevalence of cardiovascular risk factors among Japanese men from 1963 to 1994

PURPOSE

To determine trends in the incidence of cardiovascular disease in Japan, we examined observational data on coronary heart disease, stroke, and cardiovascular risk factors among urban Japanese working men.

SUBJECTS AND METHODS

The surveyed population included all male employees aged 40 to 59 years who worked for eight industrial companies in Osaka, the second largest metropolitan city in Japan. Surveillance for cardiovascular disease and risk factors was conducted from 1963 to 1994.

RESULTS

The age-adjusted incidence of coronary heart disease increased from 0.4 per 1000 person-years during 1963 to 1970, to 1.5 per 1000 person-years during 1979 to 1986, and then plateaued until 1987 to 1994 (P for trend = 0.002), whereas the incidence of stroke declined from 1.2 per 1,000 person-years during 1971 to 1978, to 0.6 per 1,000 person-years in 1987 to 1994 (P for trend = 0.02). The age-adjusted mean (+/- SD) total cholesterol level, which was 4.87 +/- 2.88 mmol/L during 1963 to 1966, increased to 5.11 +/- 0.62 mmol/L during 1982 to 1983 (P <0.001), and 5.09 +/- 0.75 mmol/L during 1990 to 1991. Both mean systolic and diastolic blood pressures increased by 1 mm Hg between the periods of 1966 to 1967 and 1982 to 1983, and declined below the 1966 to 1967 levels during 1990 to 1991. The prevalence of smoking declined from 72% during 1975 to 1976, to 58% during 1990 to 1991 (P for trend <0.001).

CONCLUSION

Although these findings were limited to urban middle-aged men, the increase in serum cholesterol is likely to attenuate the reduction in future rates of coronary heart disease in Japan that would have been expected to result from the declining prevalence of smoking.