Explanation for the Japanese paradox: prevention of increase in coronary heart disease and reduction in stroke

Trends in the prevalence of dementia in Japan

There is a paucity of data regarding trends in dementia and its subtype prevalence in Japan. Our aims in the current paper are to: (1) summarize epidemiological studies of dementia in Japan including relevant details of study protocol and diagnostic criteria, (2) compare the age-specific prevalence of all-cause dementia among studies, and (3) assess the trends in Alzheimer's disease (AD) versus vascular dementia (VaD) over time. We reviewed diagnostic criteria, all-cause dementia prevalence, and the AD/VaD ratio from 8 large population studies of dementia in Japan. Compared with the Okinawa 1992 study, studies conducted in 1994, 1998, 2005, and 2008 had a higher prevalence of all-cause dementia using Poisson regression models, after controlling for age and sex. In contrast to the US and some European countries, all-cause dementia prevalence is increasing in Japan. The prevalence of AD as opposed to VaD seems to be increasing over time, but large variability in diagnostic criteria, possible regional variability, and differences in prevalence of subtypes of dementia between men and women make it difficult to draw a conclusion about this trend at the national level. Further studies, for example, comparing the population attributable risk of vascular diseases to the prevalence and incidence of dementia could help to clarify the regional variations in etiological subtypes.

Japanese traditional miso soup attenuates salt-induced hypertension and its organ damage in Dahl salt-sensitive rats

OBJECTIVE

We investigated the effects of long-term miso soup drinking on salt-induced hypertension in Dahl salt-sensitive (Dahl S) rats.

METHODS

Dahl S rats were divided into four groups that consumed 1) water, 2) a 0.9% NaCl solution, 3) a 1.3% sodium NaCl solution, or 4) miso soup containing 1.3% NaCl. They were followed for 8 wk. Systolic blood pressure and hypertensive organ damage were determined.

RESULTS

Systolic blood pressure increased in an age- and dose-dependent manner in Dahl S rats drinking salt solutions. The systolic blood pressure increase was significantly less in the Dahl S rats that drank miso soup, although the ultimate cumulative salt loading was greater than that in the Dahl S rats given the 1.3% NaCl solution. This blood pressure decrease was associated with a morphologic attenuation of glomerular sclerosis in the kidney and collagen infiltration in the heart. Urinary protein excretions were less in the miso group than in the rats given the 1.3% NaCl solution. The fractional excretion of sodium was increased and that of potassium was decreased in Dahl S rats given the 1.3% NaCl solution, and these effects were reversed in rats given miso soup toward the values of the control.

CONCLUSION

We found that long-term miso soup drinking attenuates the blood pressure increase in salt-induced hypertension with organ damage. This may be caused by a possible retardation of sodium absorption in the gastrointestinal tract or by the direct effects of nutrients in the miso soup from soybeans. The decrease was associated with decreases in cardiovascular and renal damage.

Does high-sensitivity C-reactive protein or low-density lipoprotein cholesterol show a stronger relationship with the cardio-ankle vascular index in healthy community dwellers?: the KOBE study

AIM

High-sensitivity C-reactive protein (hs-CRP) identifies individuals at risk for cardiovascular disease (CVD) without an increased level of low-density lipoprotein cholesterol (LDL-C). The present study was performed to compare hs-CRP and LDL-C in association with the cardio-ankle vascular index (CAVI) in Japanese community dwellers considered to be at low risk for atherosclerosis from their level of traditional CVD risk factors.

METHODS

A community-based study involving 386 healthy Japanese (261 men and 125 women) without a history of CVD and medications for hypertension, diabetes, and dyslipidemia was performed. Multiple adjustments were performed with linear regression models to estimate the association between CAVI and hs-CRP or LDL-C levels. The participants were divided into four groups on the basis of whether they were above or below the median hs-CRP and LDL-C values, and CAVI was compared among the four groups by analysis of covariance after adjusting for confounders.

RESULTS

In multiple linear regression models, hs-CRP showed a significant positive association with CAVI; however, no clear association was observed between CAVI and LDL-C. These results were similar in the analyses among the participants with LDL-C <140 mg/dL or hs-CRP <1.0 mg/L. CAVI was higher in the groups with high hs-CRP than in those with low hs-CRP, irrespective of LDL-C; however, CAVI was highest in the group with high LDL-C and high hs-CRP.

CONCLUSIONS

The present study suggests that hs-CRP could be a better risk factor assessor for atherosclerosis than LDL-C in individuals considered to be at low risk for atherosclerosis assessed by their traditional CVD risk factors.

Adiponectin and smoking status: a systematic review

AIM

Smoking and adiponectin are individually associated with cardiometabolic pathologies. The present systematic review was carried out in order to summarize the association between the smoking status and circulating adiponectin levels.

METHODS

Original articles, restricted to epidemiological studies (by a cross-sectional, case-control and cohort study design) and intervention studies for adult humans, were screened for the years 1995-2010. All of the research group members then selected the eligible literature and assessed the articles in a structured systematic review manner.

RESULTS

There were 11 key studies, which included 9 articles with a cross-sectional design and 2 articles with an intervention design. Most cross-sectional studies reported lower levels of adiponectin in current smokers than in non/never smokers and/or ex-smokers, while 2 studies reported a non-significant difference in adiponectin between male smokers and non-smokers. The two intervention studies, conducted in patients on 9-week bupropion treatment and 6-month non-pharmacological treatment, reported that smoking cessation increased the adiponectin levels.

CONCLUSION

This review suggests that there is a decreased adiponectin level in current smokers and this reduction can be reversed by quitting smoking. More studies are required to confirm the findings and elucidate the biological mechanisms underlying the association between the smoking status and adiponectin levels.

Influence of smoking combined with another risk factor on the risk of mortality from coronary heart disease and stroke: pooled analysis of 10 Japanese cohort studies

BACKGROUND

In spite of the importance of a multifactorial approach to preventing cardiovascular disease in smokers, most information on the combined adverse effects of smoking and hypertension or high serum cholesterol on cardiovascular disease has been derived from Western populations, and coronary heart disease was often used as the only endpoint. Therefore, the present large-scale pooled analysis attempted to provide reliable information on the adverse effects of the coexistence of smoking and hypertension or high serum cholesterol on the risk of mortality from coronary heart disease and stroke in both, individuals and the entire population in Japan.

METHODS

A total of 27,385 male and 39,207 female participants aged 40-89 years were enrolled from 10 well-qualified Japanese cohort studies with a mean follow-up of 10.1 years. Hazard ratios and their corresponding 95% confidence intervals in smokers who had hypertension or high serum cholesterol were estimated for men and women separately using a Cox proportional hazards regression model that included age, body mass index, cohort and either serum total cholesterol or systolic blood pressure as covariates. Fractions of deaths attributable to the coexistence of these risk factors were also calculated.

RESULTS

The multivariate-adjusted hazard ratios in male and female current smokers with hypertension, compared with those with neither factor were 2.57 (95% confidence intervals, 1.51-4.38) and 6.14 (3.49-10.79) for coronary heart disease, and 3.28 (1.89-5.71) and 1.61 (0.81-3.18) for cerebral infarction, respectively. The fractions of deaths attributable to the coexistence of current smoking and hypertension in men and women were 24.6 and 9.6% for coronary heart disease and 28.1 and 2.0% for cerebral infarction, respectively. Smokers with high serum cholesterol were broadly comparable to hypertensive smokers only with respect to coronary mortality risk; the hazard ratios, compared with those with neither factor were 4.19 (2.33-7.53) for men and 3.90 (1.57-9.67) for women. The fraction of coronary deaths attributable to the coexistence of current smoking and high serum cholesterol was 6.3% in men and 2.2% in women. There was no interaction between smoking habit and blood pressure or serum total cholesterol for these two subtypes in both men and women.

CONCLUSIONS

Particular attention should be given to smokers who have concomitant hypertension or high serum cholesterol for preventing deaths due to cardiovascular disease. From a public health perspective in Japan, priority should be given to hypertensive smokers, since this group makes a large contribution to the burden of both coronary and cerebral infarction deaths.

Burden of Cardio- and Cerebro-vascular Diseases and the Conventional Risk Factors in South Asian Population

Similar to most populations, South Asian countries are also witnessing the dramatic transitions in health during the last few decades with the major causes of adverse health shifting from a predominance of nutritional deficiencies and infectious diseases to chronic diseases such as cardio and cerebrovascular disease (CVD). We summarized the available information of the burden of CVD and risk factors in the South Asian populations. The prevalence of conventional cardiovascular has been increasing among all South Asian populations. Extensive urbanization, shift in dietary pattern and sedentary daily life style is contributing towards the worsening of the CVD risk factor scenario. The burdens of the chronic cardiovascular risk factors are much prevalent in the South Asian populations. These are also rising alarmingly which ought to influence the already existed heavy CVD burden. Similar to the rest of the world, management for the conventional cardiovascular risk factors is very important for the prevention of CVD in South Asia.

Prospective care of heart failure in Japan: lessons from CHART studies

There are approximately 23 million patients with heart failure (HF) worldwide. The prognosis of patients with HF is still poor and a prospective approach for preventing and treating HF is necessary. The number of HF patients in Japan has been increasing since 1950 mainly because of a rapidly aging population. Furthermore, westernized dietary pattern, reduced physical activity, and obesity have become prominent, particularly in younger Japanese men. There is an increasing trend of diabetes and dyslipidemia, and the prevalence of smoking and hypertension continues to remain high. One of the largest HF cohorts in Japan, the CHART Studies, showed that coronary artery disease (CAD) was the most frequent etiology of HF currently. Thus, prospective strategies including accurate risk stratification, effective prevention of disease progression through evidence-based treatments, optimally personalized treatment particularly in elderly individuals, and life-long control of CAD risk factors are required to manage HF in Japan.

Exposure to particulate matter and long-term risk of cardiovascular mortality in Japan: NIPPON DATA80

AIM

It remains uncertain whether chronic exposure to particulate air pollution is associated with increased mortality in Japan because Japan has a different distribution pattern of cardiovascular disease and its risk factors compared to Western countries. We investigated the association between long-term exposure to particulate matter (PM) and cardiovascular mortality risk using a representative Japanese cohort.

METHODS

A total of 7,250 participants aged 30 years and older from 232 districts throughout Japan were followed from 1980 to 2004. We linked the averaged annual concentrations of PM from 1985 to 2004 to each cohort participant who resided in the district at the time of the baseline survey. Study participants were divided into quintiles of average PM concentration. We applied the Cox proportional hazard model adjusting for sex, age, body mass index, blood pressure, total cholesterol, blood glucose, smoking categories, drinking categories, and the municipality population size.

RESULTS

During follow-up, there were 1,716 deaths from all causes; 571 from cardiovascular disease, 116 from coronary heart disease, and 250 from stroke. Hazard ratios were not different among the quintiles and those for trend per 10 µg/m3 increase in annual PM concentration were 0.98 (95% confidence interval, 0.92-1.04) for all-cause mortality and 0.90 (95% confidence interval, 0.81-1.00) for cardiovascular mortality.

CONCLUSION

Long-term exposure to PM was not associated with increased cardiovascular mortality risk in this population-based cohort in Japan.

Physical activity in the Japan population: association with blood lipid levels and effects in reducing cardiovascular and all-cause mortality

According to many prospective cohort studies and meta-analyses of those studies, physical inactivity and/or low levels of physical fitness are associated with an elevated risk for the development of metabolic syndrome, type 2 diabetes, hypertension, coronary artery disease (CAD), and stroke, and with an increased risk of cardiovascular disease (CVD) mortality and all-cause mortality. Most of these analyses, however, were conducted on non-Japanese populations in the West. This report summarizes prospective observational and clinical studies in Japan. The annual national nutrition survey has shown a gradual decline in the number of walking steps in both genders and in all age groups over the last 10 years. While exercise habits have been gradually increasing in the elderly, only one-fifth of young and middle-aged people undertake leisure-time physical activity. Prospective cohort studies have shown that increased physical fitness and greater physical activity in either daily life or leisure time are of benefit in preventing all-cause mortality and CVD mortality. The daily number of walking steps is positively associated with HDL cholesterol levels and negatively associated with triglyceride levels. According to a random-effects model meta-analysis of 4 randomized controlled trials comparing supervised aerobic exercise training with non-exercise control in subjects without CAD, exercise resulted in a significant increase in HDL-cholesterol (10.01 mg/dL, 95% CI 5.38 to 14.65, p< 0.0001). While this confirms the importance of physical activity in preventing CVD mortality and all-cause mortality, the levels of physical activity are on a declining trend in Japan, particularly among the young.

Exploring determinants of secular decreases in childhood blood pressure and hypertension

BACKGROUND

Childhood blood pressure is largely uninfluenced by medical treatment and behavioral changes associated with hypertension diagnosis. Examining secular trends in childhood blood pressure and its contributing factors will help us better understand population-level determinants of blood pressure and hypertension.

METHODS AND RESULTS

Data were from 4 waves of the Korean National Health and Nutrition Examination Survey between 1998 and 2008, including a total of 5909 boys and girls 10 to 19 years of age. Over the past 10 years, age- and height-adjusted mean systolic blood pressure decreased substantially from 115.6 to 106.9 mm Hg (by 8.7 mm Hg) among boys and from 111.8 to 101.8 mm Hg (by 10.0 mm Hg) among girls. Associated childhood hypertension and prehypertension/hypertension prevalences decreased by 52% to 86%. These remarkable decreases were found among all age and socioeconomic groups and were not explained by secular changes in childhood obesity (body mass index and waist circumferences), health behaviors (cigarette smoking and physical activity), nutritional factors (sodium, potassium, total energy, protein, and fat intake), psychological factors (perceived stress and sleep duration), and sociodemographic factors (annual household income and family size).

CONCLUSIONS

We observed important population declines in blood pressure in Korea over a 10-year period in children 10 to 19 years of age, but the likely causes for these secular trends remain to be determined.

The Epidemiology of Stroke Amongst Women in the Asia–Pacific Region

National data from the Asia–Pacific region suggest that stroke accounts for over 10% of female deaths. With general aging in the region, and longer life expectancies for women than men, action is required to maintain recent improvements in female death rates from stroke. However, local data on incidence and risk factors for stroke amongst women are scarce. Data from 214,032 women in the Asia Pacific Cohort Studies Collaboration were thus used to investigate the risk factors for stroke in the region. Raised systolic blood pressure and diabetes were found to be key risk factors for both ischemic (IS) and hemorrhagic (HS) stroke. After adjustment for other risk factors, every extra 10 mmHg systolic blood pressure increased risk of IS by 36% and HS by 69%, whilst diabetes increased risk of IS by 170% and HS by 147%. Smoking was also an important risk factor for IS and HS; risk was reduced by quitting.

Residual lifetime risk of cardiovascular diseases in Japan

Risk assessment of cardiovascular diseases (CVD) is shifting from the relative risk to an absolute risk approach. The residual lifetime risk (LTR), which provides an absolute risk assessment, is an epidemiologic measure that expresses the probability of someone of a given age and sex developing a disease condition during their remaining lifespan. The LTR estimation is important because it could be more easily comprehended by clinicians and patients. The LTR for CVD was not estimated for the Japanese population until recently, when the LTR of stroke and acute myocardial infarction (AMI) was reported. The reported LTR of stroke and AMI for middle-aged adults is substantial. The observed probabilities illustrated that approximately 1 in 5 men and women of middle age will suffer from a stroke in their remaining lifetime. On the other hand, approximately 1 in 6 men and 1 in 9 women of middle age will suffer from AMI in their remaining lifetime. Aaginst the backdrop of the aging population and worsening risk factor scenario, these estimates re-emphasize that CVD is a public health burden that requires preventive interventions. These estimates provide a means to communicate the absolute risk of CVD to the lay population, policy makers, as well as health service providers in predicting the disease burden of CVD. This easily comprehended knowledge can be used as an important index to assist in public health education and planning.

Associations of impaired glucose metabolism and dyslipidemia with cardiovascular diseases: what have we learned from Japanese cohort studies for individualized prevention and treatment?

Metabolic disorder is a modifiable risk factor for cardiovascular diseases (CVD), and lifestyle modification is the key to improving metabolic disorder. Diabetes mellitus has been shown to be a risk factor for coronary heart disease (CHD) and ischemic stroke in both Western and Japanese populations. An association between impaired fasting glucose and pre-hypertension found in an urban Japanese population emphasized the combined risk of CVD. Mean total cholesterol levels in Japan have been increasing in the last three decades. The Japanese evidence for the positive association of total cholesterol with CHD is similar to that in the West. Higher low-density lipoprotein cholesterol (LDL-C) levels pose an increased risk of CHD and atherothrombotic infarction, whereas lower LDL-C levels may pose an increased risk of intracerebral hemorrhage in Japan. Overall, the studies reviewed here show that impaired glucose metabolism and dyslipidemia are emerging risk factors for CVD in the Japanese population.

Determinants of the omega-3 index in a Mediterranean population at increased risk for CHD

The omega-3 index, defined as the sum of EPA and DHA in erythrocyte membranes expressed as a percentage of total fatty acids, has been proposed as both a risk marker and risk factor for CHD death. A major determinant of the omega-3 index is EPA+DHA intake, but the impact of other dietary fatty acids has not been investigated. In a cross-sectional study on 198 subjects (102 men and 96 women, mean age 66 years) at high cardiovascular risk living in Spain, the country with low rates of cardiac death despite a high prevalence of cardiovascular risk factors, dietary data were acquired from FFQ and blood cell membrane fatty acid composition was measured by GC. The average consumption of EPA+DHA was 0·9 g/d and the mean omega-3 index was 7·1 %. In multivariate models, EPA+DHA intake was the main predictor of the omega-3 index but explained only 12 % of its variability (P < 0·001). No associations with other dietary fatty acids were observed. Although the single most influential determinant of the omega-3 index measured here was the intake of EPA+DHA, it explained little of the former's variability; hence, the effects of other factors (genetic, dietary and lifestyle) remain to be determined. Nevertheless, the high omega-3 index could at least partially explain the paradox of low rates of fatal CHD in Spain despite a high background prevalence of cardiovascular risk factors.

Serum levels of thiobarbituric acid-reactive substances are associated with risk of coronary heart disease

AIM

Evidence of relationships between lipid peroxidation and the incidence of coronary heart disease is limited. We therefore investigated this association in a Japanese general population.

METHODS

We prospectively studied 1945 individuals who were apparently healthy at the baseline. Cox proportional-hazards models were used to investigate the relationship between serum levels of thiobarbituric acid-reactive substances (TBARS) as a marker of lipid peroxidation and the incidence of coronary heart disease, adjusted for established risk factors including age, sex, current smoking, body mass index, systolic blood pressure, glycohemoglobin A1c, serum total cholesterol, and serum high-density lipoprotein cholesterol levels.

RESULTS

During 20,226 person-years of follow-up (median follow-up, 10.9 years), 44 coronary events were documented. The risk of coronary heart disease increased in consecutive tertiles of the TBARS level. On age-and sex-adjusted analysis, the level of TBARS was significantly associated with the incidence of coronary heart disease. The hazard ratio in the highest tertile compared with the lowest tertile was 3.22 (95% confidence interval, 1.38 to 7.53; p= 0.007). On multivariate analysis adjusted for age, sex, and other established risk factors, this association remained significant (hazard ratio, 3.23; 95% confidence interval, 1.28 to 8.16; p= 0.01).

CONCLUSIONS

Serum levels of TBARS are a strong and independent predictor of coronary heart disease. These findings support the hypothesis that lipid peroxidation is an important risk factor for coronary heart disease.

Development of a model for prediction of coronary atherosclerotic regression: evaluation of high-density lipoprotein cholesterol level and peripheral blood monocyte count

Monocytes and high-density lipoprotein cholesterol (HDL-C) play important roles in the process of coronary atherosclerosis. We hypothesized that a reasonable predictive model of coronary plaque regression might be constructed using the change in the peripheral monocyte count and the serum HDL-C level. The plaque volume, as assessed by volumetric intravascular ultrasound, was measured at the baseline and after 6 months of pravastatin therapy in 114 patients with coronary artery disease. After 6 months of pravastatin therapy, a significant decrease of the plaque volume by 9.9% (p < 0.0001, vs. baseline) was observed; furthermore, a corresponding increase of the serum HDL-C level and decrease of the peripheral blood monocyte count were also seen (12.5%, p < 0.01 and -7.3%, p < 0.0001). In a multivariate regression analysis using the serum lipids and traditional risk factors as the covariates, the increase in the serum HDL-C (β -0.56, p < 0.0001) and the decrease in monocyte count (β 0.23, p = 0.03) were identified as independent predictors of the plaque regression. A model for the prediction of plaque regression according to whether the achieved the change in (Δ) monocyte count and ΔHDL-C were above or below the median values was prepared. Among the four groups, the group with ΔHDL-C ≥8.8% and Δmonocyte count ≤-8.6% showed the largest plaque regression (-20.4%), and the group with ΔHDL-C <8.8% and Δmonocyte count >-8.6% showed the increase of the plaque volume (2.6%). In view of the inflammatory nature of atherosclerosis, the model constructed using the two predictors may be a useful model for the prediction of plaque regression.

Clinical characteristics and long-term prognosis of vasospastic angina patients who survived out-of-hospital cardiac arrest: multicenter registry study of the Japanese Coronary Spasm Association

BACKGROUND

Coronary artery spasm plays an important role in the pathogenesis of ischemic heart disease; however, its role in sudden cardiac death remains to be fully elucidated. We examined the clinical characteristics and outcomes of patients with vasospastic angina (VSA) in our nationwide multicenter registry by the Japanese Coronary Spasm Association.

METHODS AND RESULTS

Between September 2007 and December 2008, 1429 patients with VSA (male/female, 1090/339; median, 66 years) were identified. They were characterized by a high prevalence of smoking and included 35 patients who survived out-of-hospital cardiac arrest (OHCA). The OHCA survivors, as compared with the remaining 1394 non-OHCA patients, were characterized by younger age (median, 58 versus 66 years; P<0.001) and higher incidence of left anterior descending coronary artery spasm (72% versus 53%, P<0.05). In the OHCA survivors, 14 patients underwent implantable cardioverter-defibrillator (ICD) implantation while intensively treated with calcium channel blockers. Survival rate free from major adverse cardiac events was significantly lower in the OHCA survivors compared with the non-OHCA patients (72% versus 92% at 5 years, P<0.001), including appropriate ICD shocks for ventricular fibrillation in 2 patients. Multivariable analysis revealed that OHCA events were significantly correlated with major adverse cardiac events (hazard ratio, 3.25; 95% confidence interval, 1.39 to 7.61; P<0.01).

CONCLUSIONS

These results from the largest vasospastic angina cohort indicate that vasospasm patients who survived OHCA are high-risk population. Further studies are needed to determine whether implantable cardioverter-defibrillator therapy improves patient prognosis.

Epidemiology and prevention of hypertension in Japanese: how could Japan get longevity?

Japan is one of the countries with the longest longevity in the world, and it was accomplished by a drastic decline in stroke mortality from 1960's. The decline in stroke mortality would be largely explained by a population-wide decreasing trend in blood pressure (BP) level, because higher BP has been the strongest risk factor of stroke; about 20% of total deaths can be explained by higher BP above optimal in Japan. Decreasing trend in BP occurred both in men and women in all age-groups, which cannot be fully explained by the widespread use of anti-hypertensive agents. The most probable reason for the population-wide BP decline in Japan would be a large decline in dietary salt intake after 1950's. However, other factors including obesity, high alcohol intake, and unfavorable dietary habits could increase BP level of Japanese again.

Developments for a growing Japanese patient population: facilitating new technologies for future health care

Lung cancer, COPD and cardiovascular diseases are highlighted as some of the most common disease that cause mortality, and for that reason are the most active areas for drug development. This perspective paper overviews the urgent need to develop a health care system for a rapidly growing patient population in Japan, including forthcoming demands on clinical care, expecting outcomes, and economics. There is an increasing requirement to build on the strengths of the current health care system, thereby delivering urgent solutions for the future. There is also a declaration from the Ministry of Health, Labour and Welfare (MHLW), to develop new biomarker diagnostics, which is intended for patient stratification, aiding in diagnostic phenotype selection for responders to drug treatment of Japanese patients. This perspective was written by the panel in order to introduce novel technologies and diagnostic capabilities with successful implementation. The next generation of personalized drugs for targeted and stratified patient treatment will soon be available in major disease areas such as, lifestyle-related cancers, especially lung cancers with the highest mortality including a predisposing disorder chronic obstructive pulmonary disease, cardiovascular disease, and other diseases. Mass spectrometric technologies can provide the "phenotypic fingerprint" required for the concept of Personalized Medicine. Mass spectrometry-driven target biomarker diagnoses in combination with high resolution computed tomography can provide a critical pathway initiative facilitated by a fully integrated e-Health infrastructure system. We strongly recommend integrating validated biomarkers based on clinical proteomics, medical imaging with clinical care supported by e-Health model to support personalized treatment paradigms to reduce mortality and healthcare costs of chronic and co-morbid diseases in the elderly population of Japan.

Premature mortality due to stroke and trend in stroke mortality in Japan (1980-2005)

BACKGROUND

Although a downward trend in stroke mortality over the last decades has been observed in many countries, stroke remains an important contributor to the total burden of disease. In the present study, we provided additional measures, namely years of life lost (YLLs) and average years of life lost (AYLLs) to reflect the burden of this condition in Japan.

METHODS

We obtained stroke mortality data for Japan from the World Health Organization mortality database for the period 1980-2005 to analyze trends of age-standardized rates (ASRs) per 100,000 of stroke mortality. YLLs and AYLLs were also estimated according to Japanese life tables.

RESULTS

Decreases in ASRs by 68% in men and by 74% in women were observed at the end of this study period. In men, there were total of 1,684,482 YLLs in 1980; 776,350 in 1995 and 745,636 in 2005, corresponding to an overall AYLLs for all stroke deaths of 20.6; 11.2 and 11.7 years earlier than expected, respectively. In women, the respective numbers were 1,567,817 YLLs in 1980; 810,135 in 1995 and 726,650 in 2005, corresponding to an overall AYLLs for all stroke deaths of 19.4; 10.5 and 10.5 years.

CONCLUSIONS

The findings showed shorter AYLLs due to stroke in Japan, suggesting that stroke patients died from this condition at older age at the end of the study period. This change in premature mortality was consistent with decreased trend in the stroke mortality.

Influence of cataract surgery and blood pressure changes caused by sodium restriction on retinal vascular diameter

PURPOSE

To investigate the impact of cataract surgery and blood pressure changes induced by one week of sodium restriction on retinal vascular diameter.

METHODS

Fundus photographs of 200 patients were obtained before and one week after cataract surgery. For one week after admission, 100 patients received sodium restriction and 100 patients (ie, the control group) did not receive sodium restriction. The diameter of the retinal vessels and blood pressure were compared between the sodium restriction group and the control group. The vascular diameter was measured using an objective computer-based method.

RESULTS

Neither group had a significant change in the diameter of the retinal vessels after cataract surgery. Although there was no significant change in retinal arterial and venular diameter in the sodium restriction group, one-week sodium restriction significantly reduced mean blood pressure. However, multiple linear regression analyses indicated that an increase in retinal arteriolar diameter was significantly associated with diabetes, hyperlipidemia, and alcohol intake.

CONCLUSION

Cataract surgery and blood pressure reduction induced by one week of sodium restriction resulted in no significant change in retinal arteriolar diameter.

[Cholesterol controversy: cutoff point of low-density lipoprotein cholesterol level in Guidelines by Japan Atherosclerosis Society]

In 2007, the Japan Atherosclerosis Society published the Guidelines for prevention of atherosclerotic cardiovascular diseases. However, the guidelines have several flaws with regard to the cutoff level of serum low-density lipoprotein cholesterol (LDL-C). First, LDL-C level is used instead of serum total cholesterol (TC) level in the guidelines. In this case, they must show at least some basic data on the relationship between LDL-C level and mortality or morbidity from coronary heart disease (CHD). Second, it was recommended that the LDL-C level be below 140 mg/dL or 3.6 mmol/L (corresponding to a TC level of 220 mg/dL or 5.7 mmol/L, respectively). These levels are unreasonable considering that the TC levels of 240-260 mg/dL are optimal in terms of all-cause mortality for the Japanese population. Third, although there are big differences in mortality and morbidity from CHD between sexes, they discussed the matter without considering these differences. Last but not least, the conflict of interest of the editors of the guidelines has never been disclosed. The Japanese population has a lower CHD mortality and incidence than populations from other industrialized countries despite an increase in serum TC level in the former. In populations with a markedly lower coronary mortality or morbidity such as the Japanese population, it is still important to determine the optimal cutoff level of LDL-C to prevent the development of CHD and other atherosclerotic diseases.

Association of central systolic blood pressure with intracerebral small vessel disease in Japanese

BACKGROUND

Recent studies have reported the association between advanced arterial stiffness and brain small vessel diseases (SVDs). Two possible hemodynamic mechanisms, increases in central blood pressure (BP) and pulsatile flow load to the brain, have been speculated to link arterial stiffness and SVD. The carotid flow augmentation index (AI) has been proposed as an index of pulsatile flow to the brain. We compared its association with brain SVD with that of central BP in a general population.

METHODS

Subjects were 500 individuals free from symptomatic cardiovascular diseases with a mean age of 66.9 +/- 8.4 years. Brachial-ankle pulse wave velocity (baPWV) was measured as an index of arterial stiffness. Carotid flow AI was obtained by Doppler ultrasonography. The presence of silent cerebral lacunar infarcts (SCI) was determined as a manifestation of SVD by 3-tesla magnetic resonance imaging (MRI). Second peak radial systolic BP (SBP2) and pulse pressure (PP2) were used as estimates of central BP.

RESULTS

baPWV was significantly associated with radial BP2 (r = 0.55, P < 0.0001) but not with carotid flow AI (r = 0.03, P = 0.51). Radial BPs and baPWV, but not flow AI, were significantly higher in subjects with SCI. Radial SBP2 had higher odds ratio for the presence of SCI than brachial SBP, PP, and radial PP2. Logistic regression analysis showed that radial SBP2, but not flow AI, was independently related to the presence of SCI.

CONCLUSION

These findings indicate that the SBP2, an estimate of central SBP, is significantly associated with the presence of SVD in an apparently healthy general population.

Medical expenditures of men with hypertension and/or a smoking habit: a 10-year follow-up study of National Health Insurance in Shiga, Japan

Hypertension and smoking are major causes of disability and death, especially in the Asia-Pacific region, where there is a high prevalence of a combination of these two risk factors. We attempted to measure the medical expenditures of a Japanese male population with hypertension and/or a smoking habit over a 10-year period of follow-up. A cohort study was conducted that investigated the medical expenditures due to a smoking habit and/or hypertension during the decade of the 1990s using existing data on physical status and medical expenditures. The participants included 1708 community-dwelling Japanese men, aged 40-69 years, who were classified into the following four categories: 'neither smoking habit nor hypertension', 'smoking habit alone', 'hypertension alone' or 'both smoking habit and hypertension.' Hypertension was defined as a systolic blood pressure of > or =140 mm Hg, a diastolic blood pressure of > or =90 mm Hg or taking antihypertensive medications. In the study cohort, 24.9% had both a smoking habit and hypertension. During the 10-year follow-up period, participants with a smoking habit alone (18,444 Japanese yen per month), those with hypertension alone (21,252 yen per month) and those with both a smoking habit and hypertension (31,037 yen per month) had increased personal medical expenditures compared with those without a smoking habit and hypertension (17,418 yen per month). Similar differences were observed even after adjustment for other confounding factors (P<0.01). Japanese men with both a smoking habit and hypertension incurred higher medical expenditures compared with those without a smoking habit, hypertension or their combination.

What psychosocial characteristics are associated with smoking cessation behavior and readiness to quit smoking among Japanese male ever-smokers with type 2 diabetes mellitus?

AIM

The relationship between psychosocial characteristics and smoking cessation behavior was examined among Japanese male eversmokers with type 2 diabetes mellitus.

METHODS

The psychosocial characteristics and smoking cessation behavior of 441 male ever-smokers with type 2 diabetes mellitus were investigated. Personality was assessed using an egogram (five ego states: the Critical Parent, Nurturing Parent, Adult, Free Child, and Adapted Child) and each patient was classified into a high score or low score group based on the median. The current smokers were divided into 2 categories according to their readiness to quit smoking.

RESULTS

In multivariate analyses, the ever-smokers with a high Adult score had a lower risk of current smoking (OR=0.67, 95%CI=0.41-0.93), the ever-smokers with a high Free Child score were over 3 times more likely to currently smoke (OR=3.12, 95%CI=1.97-4.97), and the ever-smokers who had a low educational background had a higher risk of current smoking (OR=3.02, 95% CI=1.73-5.28). In addition, the current smokers with a high Adult score had a lower risk of being in the immotive and precontemplation stage (OR=0.55, 95%CI=0.24-0.96). The current smokers who had a low educational background had a higher risk of being in the immotive and precontemplation stage (OR=2.13, 95%CI=1.08-5.42).

CONCLUSION

There is a need to develop a smoking cessation program for patients with high "Free Child" scores and a "low education level".

Omega-3 Index and sudden cardiac death

Sudden cardiac death (SCD) is an unresolved health issue, and responsible for 15% of all deaths in Western countries. Epidemiologic evidence, as well as evidence from clinical trials, indicates that increasing intake and high levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) protect from SCD and other major adverse cardiac events. Levels of EPA+DHA are best assessed by the Omega-3 Index, representing the red cell fatty acid content of EPA+DHA. Work is in progress that will further define the value of the Omega-3 Index as a risk factor for SCD, other cardiac events, and as target for treatment with EPA+DHA.

Shift-work and cardiovascular disease: a population-based 22-year follow-up study

Studies on the association between shift-work and cardiovascular disease (CVD), in particular coronary heart disease (CHD), have given conflicting results. In this prospective population-based study we assessed the association of shift-work with three endpoints: CHD mortality, disability retirement due to CVD, and incident hypertension. A cohort of 20,142 adults (the Finnish Twin Cohort) was followed from 1982 to 2003. Type of working time (daytime/nighttime/shift-work) was assessed by questionnaires in 1975 (response rate 89%) and in 1981 (84%). Causes of death, information on disability retirement and hypertension medication were obtained from nationwide official registers. Cox proportional hazard models were used to obtain hazard ratios (HR) for each endpoint by type of working time. Adjustments were made for 14 socio-demographic and lifestyle covariates. 76.9% were daytime workers and 9.5% shift-workers both in 1975 and in 1981. During the follow-up, 857 deaths due to CHD, 721 disability retirements due to CVD, and 2,642 new cases of medicated hypertension were observed. However, HRs for shift-work were not significant (mortality HR men 1.09 and women 1.22; retirement 1.15 and 0.96; hypertension 1.15 and 0.98, respectively). The results were essentially similar after full adjustments for all covariates. Within twin pairs, no association between shift work and outcome was observed. Our results do not support an association between shift-work and cardiovascular morbidity.

Polyunsaturated fatty acid levels of serum and red blood cells in apparently healthy Japanese subjects living in an urban area

AIM

We assessed levels of polyunsaturated fatty acid (PUFA) in serum and red blood cells (RBCs) among groups stratified by generation and its clinical significance in Japanese subjects living in an urban area.

METHODS

We enrolled 200 apparently healthy Japanese (126 males, mean age: 50.3+/-9.2 years) living in an urban area. Levels of PUFA, including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA), and dihomo-gamma-linolenic acid (DGLA) in serum and RBCs were measured for each generation (G1 <35y, G2 35y-<45y, G3 45y-<55y, G4 55y-<65y, G5>or=65y).

RESULTS

No significant differences in EPA, DHA, AA, or EPA/AA were observed between males and females. After dividing into generations, stepwise increases in EPA and DHA, but not DGLA or AA, were observed in serum (all p<0.0001). EPA/AA ratios were stepwisely increased in serum (mean: G1:0.26, G2:0.29, G3:0.43, G4:0.58, G5:0.68, p<0.0001) and RBCs (mean: G1:0.10, G2:0.09, G3:0.15, G4:0.20, G5:0.23, p<0.0001). Positive correlations of EPA (r=0.83), DHA (r=0.55), DGLA (r=0.54), AA (r=0.29), and EPA/AA (r=0.91) were demonstrated between serum and RBCs. In addition, a significant positive correlation between EPA/AA ratios and insulin sensitivity as well as a negative correlation between those ratios and insulin resistance were observed in subjects with metabolic syndrome.

CONCLUSION

Low levels of EPA/AA, which were associated with insulin resistance, were demonstrated in young Japanese adults living in an urban area.

Home and Office Blood Pressure Control among Treated Hypertensive Patients in Japan: Findings from the Japan Home versus Office Blood Pressure Measurement Evaluation (J-HOME) Study

Appropriate control of blood pressure (BP) is essential for prevention of future cardiovascular events. However, BP control among treated hypertensive patients has been insufficient. Recently, the usefulness of self-measured BP at home (home BP measurement) for the management of hypertension has been reported in many studies. We evaluated BP control both at home and in the office among treated hypertensive patients in primary care settings in Japan (the J-HOME study). We found poor control of home and office BPs and clarified some factors affecting control. We also examined factors associated with the magnitude of the white-coat effect, the morning–evening BP difference, and home heart rate in this J-HOME study.

Trends in acute myocardial infarction incidence and mortality over 30 years in Japan: report from the MIYAGI-AMI Registry Study

BACKGROUND

Worldwide, the rate of aging is highest in Japan, especially the female population. To explore the trends for acute myocardial infarction (AMI) in Japan, the MIYAGI-AMI Registry Study has been conducted for 30 years since 1979, whereby all AMI patients in the Miyagi prefecture are prospectively registered.

METHODS AND RESULTS

In 1979-2008, 22,551 AMI patients (male/female 16,238/6,313) were registered from 43 hospitals. The age-adjusted incidence of AMI (/100,000persons/year) increased from 7.4 in 1979 to 27.0 in 2008 (P<0.001). Although control of coronary risk factors remained insufficient, the rates of ambulance use and primary percutaneous coronary intervention (PCI) have increased, and the overall in-hospital mortality (age-adjusted) has decreased from 20.0% in 1979 to 7.8% in 2008 (P<0.0001). However, the in-hospital mortality remains relatively higher in female than in male patients (12.2% vs 6.3% in 2008). Female patients were characterized by higher age and lower PCI rate.

CONCLUSIONS

The MIYAGI-AMI Registry Study demonstrates the steady trend of an increasing incidence, but decreasing mortality, for AMI in Japan over the past 30 years, although the female population still remains at higher risk for in-hospital death, despite improvements in the use of ambulances and primary PCI. (Circ J 2010; 74: 93 - 100).

Mortality from cardiovascular and cerebrovascular diseases in Europe and other areas of the world: an update

OBJECTIVE

To update trends in mortality from coronary heart diseases (CHD) and cerebrovascular diseases (CVD) over the period 1981-2004 in Europe, the USA, Latin America, Japan and other selected areas of the world.

METHODS

Age-standardized mortality rates were derived from the World Health Organization database. Joinpoint analysis was used to identify significant changes in trends.

RESULTS

In the European Union (27 countries), CHD mortality in men declined from 139/100,000 in 1985-1989 to 93/100,000 in 2000-2004 (-33%). In women, the fall was from 61/100,000 to 44/100,000 (-27%). In this area, a decline by over 30% was also registered in CVD mortality for both sexes. In the Russian Federation and other countries of the former Soviet Union, CHD rates in 2000-2004 were exceedingly high, around 380/100,000 men and 170/100,000 women in Russia, 430 for men and 240 for women in Ukraine, 420 and 200 in Belarus. For CVD, a similar situation was registered, with mortality rates of 226/100,000 for men and 159/100,000 for women in 2004 in the Russian Federation, and more than 24% increase since the late 1980s for men and 15% for women. CHD and CVD mortality continued to decline in most Latin American countries, Australia and other areas considered, including Asia (even if with marked differences).

CONCLUSION

Although mortality from CHD and CVD continues to decline in several areas of the world including most countries of Europe and of the America providing data and Australia, unfavourable trends were still observed in the Russian Federation and other countries of the former Soviet Union, whose recent rates remain exceedingly high.