Trends in fatal coronary heart disease among people aged 25-74 years in Oita City, Japan, from 1987-1998

Dietary sodium-to-potassium ratio as a risk factor for stroke, cardiovascular disease and all-cause mortality in Japan: the NIPPON DATA80 cohort study

OBJECTIVES

To evaluate the impact of dietary sodium and potassium (Na-K) ratio on mortality from total and subtypes of stroke, cardiovascular disease (CVD) and all causes, using 24-year follow-up data of a representative sample of the Japanese population.

SETTING

Prospective cohort study.

PARTICIPANTS

In the 1980 National Cardiovascular Survey, participants were followed for 24 years (NIPPON DATA80, National Integrated Project for Prospective Observation of Non-communicable Disease And its Trends in the Aged). Men and women aged 30-79 years without hypertensive treatment, history of stroke or acute myocardial infarction (n=8283) were divided into quintiles according to dietary Na-K ratio assessed by a 3-day weighing dietary record at baseline. Age-adjusted and multivariable-adjusted HRs were calculated using the Mantel-Haenszel method and Cox proportional hazards model.

PRIMARY OUTCOME MEASURES

Mortality from total and subtypes of stroke, CVD and all causes.

RESULTS

A total of 1938 deaths from all causes were observed over 176 926 person-years. Na-K ratio was significantly and non-linearly related to mortality from all stroke (p=0.002), CVD (p=0.005) and total mortality (p=0.001). For stroke subtypes, mortality from haemorrhagic stroke was positively related to Na-K ratio (p=0.024). Similar relationships were observed for men and women. The observed relationships remained significant after adjustment for other risk factors. Quadratic non-linear multivariable-adjusted HRs (95% CI) in the highest quintile versus the lowest quintile of Na-K ratio were 1.42 (1.07 to 1.90) for ischaemic stroke, 1.57 (1.05 to 2.34) for haemorrhagic stroke, 1.43 (1.17 to 1.76) for all stroke, 1.39 (1.20 to 1.61) for CVD and 1.16 (1.06 to 1.27) for all-cause mortality.

CONCLUSIONS

Dietary Na-K ratio assessed by a 3-day weighing dietary record was a significant risk factor for mortality from haemorrhagic stroke, all stroke, CVD and all causes among a Japanese population.

Trends in out-of-hospital ischemic heart disease mortality for the 25-64 year old population of Kaunas, Lithuania, based on data from the 1988-2012 Ischemic Heart Disease Registry

AIM

The aim of the study was to evaluate trends in out-of-hospital ischemic heart disease (IHD) mortality in the Kaunas, Lithuania population aged 25-64, from 1988 to 2012.

METHODS

The registry was maintained according to the World Health Organisation (WHO) recommendations for the multinational MONICA (MONItoring of trends and determinants in CArdiovascular disease) project. We analysed out-of-hospital deaths from IHD, by sex and age groups, using the linear logistic regression model for identifying trends.

RESULTS

In 1988-2012, the out-of-hospital IHD deaths in Kaunas accounted for 78.4% and 68.4%, on average, of all IHD deaths in men and women aged 25-64, respectively. During the study period, the out-of-hospital IHD mortality for the Kaunas population aged 25-64 was 134.5 per 100,000 men and 18.2 per 100,000 women. From 1988 to 2012, the out-of-hospital IHD mortality for men and women aged 25-64 tended to decline by, on average, 8.3% per year (p = 0.269) and 16.2% per year (p = 0.101), respectively; whereas the corresponding rates for men aged 25-44 were declining significantly, by 22.5% per year (p = 0.047). The most significant changes in out-of-hospital IHD mortality were among men aged 25-44 with no previous history of acute myocardial infarction (AMI), in whom the out-of-hospital IHD mortality was significantly declining, by 21.3% per year (p = 0.015); whereas the corresponding rates for men aged 45-54 with a previous history of AMI tended to decline by 20.4% per year (p = 0.114).

CONCLUSIONS

In 1988-2012, the out-of-hospital IHD deaths of younger men and middle-aged women accounted for the highest percentage of all IHD deaths; and a higher proportion of both men and women with no previous history of AMI, as compared to the proportion of those with a previous history of AMI.

Variation in rates of fatal coronary heart disease by neighborhood socioeconomic status: the atherosclerosis risk in communities surveillance (1992-2002)

PURPOSE

Racial and gender disparities in out-of-hospital deaths from coronary heart disease (CHD) have been well-documented, yet disparities by neighborhood socioeconomic status (nSES) have been less systematically studied in US population-based surveillance efforts.

METHODS

We examined the association of nSES, classified into tertiles, with 3,743 out-of-hospital fatal CHD events, and a subset of 2,191 events classified as sudden, among persons aged 35 to 74 years in four US communities under surveillance by the Atherosclerosis Risk in Communities (ARIC). Poisson generalized linear mixed models generated age-, race- (white, black) and gender-specific standardized mortality rate ratios and 95% confidence intervals (RR, 95% CI).

RESULTS

Regardless of nSES measure used, inverse associations of nSES with all out-of-hospital fatal CHD and sudden fatal CHD were seen in all race-gender groups. The magnitude of these associations was larger among women than men. Further, among blacks, associations of low nSES (vs. high nSES) were stronger for sudden cardiac deaths (SCD) than for all out-of-hospital fatal CHD.

CONCLUSIONS

Low nSES was associated with an increased risk of out-of-hospital CHD death and SCD. Measures of the neighborhood context are useful tools in population-based surveillance efforts for documenting and monitoring socioeconomic disparities in mortality over time.

Methodology of studies evaluating death certificate accuracy were flawed

BACKGROUND AND OBJECTIVE

Statistics on causes of death are important for epidemiologic research. Studies that evaluate the source data often give conflicting results, which raise questions about comparability and validity of methods.

METHODS

For 44 recent evaluation studies we examined the methods employed and assessed the reproducibility.

RESULTS

Thirty studies stated who reviewed the source data. Six studies reported reliability tests. Twelve studies included all causes of death, but none specified criteria for identifying the underlying cause when several, etiologically independent conditions were present. We assessed these as not reproducible. Of 32 studies that focussed on a specific condition, 21 provided diagnostic criteria such that the verification of the focal diagnosis is reproducible. Of 16 that discussed the difference between dying "with" and "from" a condition, eight described how competing causes had been handled. For these eight, the selection of a principal cause is reproducible, but in three the selection strategy conflicts with the international instructions issued by the World Health Organization.

CONCLUSION

Methods and criteria are often insufficiently described. When described, they sometimes disagree with the international standard. Explicit descriptions of methods and criteria would contribute to methodologic improvement and would allow readers to assess the generalizability of the conclusions.

Contributions of mortality changes by age group and selected causes of death to the increase in Japanese life expectancy at birth from 1950 to 2000

The purpose of this study is to analyze contributions of mortality change by age group and selected causes of death to the increase in life expectancy at birth from 1950 to 2000 in Japan, which has the longest longevity in the world. Using mortality data from Japanese vital statistics from 1950 to 2000, we analyzed contributions of mortality change by age group and selected causes of death to the increase in life expectancy at birth by the method of decomposition of changes and calculated age-adjusted death rates for selected causes of death. Gastroenteritis, tuberculosis and pneumonia largely contributed to an increase in life expectancy in childhood and in the young in the 1950s and 1960s. The largest contributing disease changed from tuberculosis and pneumonia in earlier decades to cerebrovascular diseases in the 1970s. The largest contributing age group also shifted to older age groups. Age-adjusted death rate for cerebrovascular diseases in 2000 was one fifth of the 1965 level. Cerebrovascular diseases contributed to an increase in life expectancy at birth of 2.9 years in males and 3.1 years in females from 1970 to 2000. In the 1990s, the largest contributing age group, both among males and among females, was the 75-84 age group. Of the selected causes of death, heart diseases other than ischemic heart disease became the largest contributor to the increase in life expectancy at birth. Unlike cerebrovascular diseases, cancer and ischemic heart disease contributed little to change in life expectancy at birth over the past 50 years. In conclusion, although mortality from ischemic heart disease has not increased since 1970 and remained low compared with levels in western countries, mortality from cerebrovascular diseases has dramatically decreased since the mid-1960s in Japan. This gave Japan the longest life expectancy at birth in the world. It is necessary to study future trends in life expectancy at birth in Japan.

Review of efficacy of rosuvastatin 5 mg

The prevalence of coronary heart disease (CHD) has been increasing in the past few decades in Japan, as it has in industrialised countries worldwide. CHD risk can be substantially reduced by lowering low-density lipoprotein cholesterol (LDL-C) in patients with dyslipidaemia. Statins are highly effective for this indication, but many patients treated with these drugs still do not meet their treatment goals, often because clinicians fail to titrate these patients to a higher, potentially more effective, dose. Thus, there is a need for more effective agents that can help patients reach their goals at starting doses. This paper reviews key clinical results for a new agent, rosuvastatin. The data show that rosuvastatin 5 mg is highly effective in lowering LDL-C to recommended levels for most patients (mean reductions ranging from 42 to 52%). In addition, rosuvastatin 5 mg effectively lowers triglycerides (-16%), total cholesterol (-30%), non-high-density lipoprotein cholesterol (non-HDL-C; -38%) and apolipoprotein (apo) B levels (-33%) and increases HDL-C (+8.2-13%) in a wide range of patients with hypercholesterolaemia, including the elderly, obese patients, postmenopausal women and patients with hypertension, CHD, diabetes and metabolic syndrome. The 5-mg dose of rosuvastatin dose also produces greater reductions in LDL-C and larger increases in HDL-C than recommended initial doses of atorvastatin, simvastatin or pravastatin (for LDL-C reductions, p <0.001 vs. atorvastatin 10 mg, simvastatin 20 mg and pravastatin 20 mg; for HDL-C elevations, p <0.01 vs. atorvastatin 10 mg). These results demonstrate that rosuvastatin 5 mg produces favourable effects on the lipid profile and helps more patients achieve LDL-C goals than comparator statins.

Resting heart rate and cause-specific death in a 16.5-year cohort study of the Japanese general population

BACKGROUND

Several prospective studies have reported resting heart rate (HR) to be a risk factor for certain cause-specific death, together with sex- or age-specific differences in the effects of HR on death. However, there have been few prospective data from non-Western populations.

METHODS

Cohort study, over 16.5 years to date of death or end of follow-up (November 15, 1998) involving 8800 men and women > or =30 years of age randomly selected throughout Japan, who participated in the National Survey on Circulatory Disorders in 1980. Resting HR was determined from 3 consecutive intervals between R waves on the 12-lead electrocardiogram.

RESULTS

For middle-aged men (30 to 59 years of age), in the highest quartile of HR, there was a significant positive association with cardiovascular (RR, 2.55; 95% CI, 1.22 to 5.31) and all-cause death (RR, 1.45; 95% CI, 1.06 to 2.00). For middle-aged women, in the highest quartile, there was a significant positive association with noncancer, noncardiovascular (RR, 2.41; 95% CI, 1.04 to 5.59), and all-cause death (RR, 1.94; 95% CI, 1.26 to 3.01). Resting HR also showed a significant positive association with cardiac events but not to stroke. These relations were not evident for elderly subjects (> or =60 years of age). Results were not affected when deaths within the first 5 years of follow-up were excluded, except for noncancer, noncardiovascular death.

CONCLUSIONS

High resting HR is an independent predictor of long-term death in the Japanese general population.

Some puzzling situations in the onset, occurrence and future of coronary heart disease in developed and developing populations, particularly such in sub-Saharan Africa

Coronary heart disease (CHD) was rare in developed populations until the early 1900s; this prevailed even among the small segments who were prosperous and who, in measure, had most of the currently recognised risk factors. However, in the 1930s, with improved circumstances from general rises in socio-economic state, there were major increases in the occurrence and mortality rate from the disease, the latter reaching a third of the total mortality in some countries, as in the United Kingdom (UK). Puzzlingly, the inter-population diversity of the increases in CHD has been such that there are as much as five fold differences in CHD mortality rates, as, for example, between Poland and Spain. Within recent years, with appropriate treatments, the mortality rate has halved in some countries, again, as in the UK. However, the incidence rate of the disease has diminished little or hardly at all. Risk factors include a familial component and, nutritionally, over-eating, a high fat intake, relatively low intakes of plant foods, especially of vegetables and fruit and, non-nutritionally, smoking, excessive alcohol consumption and a low level of everyday physical activity. On the one hand, known risk factors, broadly, are considered to be capable of explaining only about half of the variation in the occurrence of the disease. Even at present, known risk factors far from fully explain the epidemiological differences in mortality rates. Yet, on the other hand, there is abundant evidence that in population groups, among whom risk factors are low or have been reduced, CHD incidence and mortality rates are lower. Notwithstanding this knowledge, broadly, there is very little interest in the general public in taking avoiding measures. As to the situation in developing populations, in sub-Saharan Africa, in urban Africans, as in Johannesburg, South Africa, despite considerable westernisation of life style and with rises in risk factors, CHD remains of very low occurrence, the situation thereby resembling, historically, its relatively slow emergence in developed populations. In most eastern countries, mortality rates remain relatively low, as in Russia and Japan. However, in major contrast, in India, rates have risen considerably in urban dwellers. Indeed, in Indian immigrants, as in those in the UK, their rate actually exceeds that in the country's white population. In brief, much remains to be explained in the epidemiology of the disease.