Stroke incidence and case fatality in Shiga, Japan 1989-1993

Associations between Supper Timing and Mortality from Cardiovascular Disease among People with and without Hypertension

AIM

Less is known about the impact of supper time on cardiovascular disease (CVD) risk among hypertensives and nonhypertensives. We aimed to explore this issue in a cohort study.

METHODS

We analyzed the data of 72,658 participants (15,386 hypertensives and 57,272 nonhypertensives) aged 40-79 years without a history of CVD at baseline (1988-1990) under the Japan Collaborative Cohort study. Supper time was assessed based on self-reported questionnaires categorized as before 17:00, between 17:00 and 20:00, after 20:00, irregular supper time, and reference supper time (17:00-20:00). Hazard ratios (HRs) and 95% confidence intervals (95% CI) of CVD mortality were calculated according to supper time after adjustment for potential confounders, stratified by hypertensive status and age group (＜65 and ≥ 65 years).

RESULTS

During a median of 19.4 years of follow-up, 4,850 CVD deaths were recorded. Compared with the reference time, the risk of CVD mortality was higher for irregular supper time for the total population, either hypertensives or nonhypertensives, more specifically hypertensives aged ≥ 65 years; the multivariable HR (95% CI) of CVD mortality in the total population was 1.28 (1.11-1.50, P＜0.01). The supper time of ＞20:00 tended to be associated with the higher risk only for hypertensives; the multivariable HR was 1.39 (0.98-1.96, P=0.06).

CONCLUSION

Irregular supper time was associated with an increased risk of CVD mortality. Supper timing could be a surrogate marker for CVD risk.

Atrial Fibrillation With and Without Cardiovascular Risk Factors and Stroke Mortality

Aim: The association between atrial fibrillation (AF) and risk of stroke mortality among men and women without traditional cerebrocardiovascular risk factors (TCVRFs) is unclear. This study aimed to determine whether AF was a risk factor for stroke and total cardiovascular disease mortality among individuals without TCVRFs.

Methods: A total of 90,629 Japanese subjects from the Ibaraki Prefectural Health Study aged 40–79 years, with and without TCVRFs, were studied from 1993 to 2013. Hazard ratios (HRs) were calculated using the Cox proportional hazard regression model stratified by sex and the presence of TCVRFs. Covariates were age, systolic blood pressure, anti-hypertensive medication use, and serum total cholesterol levels. A standard 12-lead electrocardiogram at rest was used to screen AF. Cause-specific mortality was classified according to the International Classification of Disease code.

Results: Compared with participants without AF, multivariable-adjusted hazard ratios (with 95% confidence intervals) for stroke mortality among participants without TCVRFs were 4.3 (1.1–17.8) and 15.0 (5.5–40.8) for men and women with AF, respectively. HRs for total cardiovascular disease mortality were 6.2 (2.8–14.2) for men and 10.7 (4.8–24.1) for women. For participants with TCVRFs, multivariable-adjusted HRs for stroke mortality were 3.1 (2.2–4.6) and 4.3 (2.6–7.3), whereas HRs for total cardiovascular disease mortality were 2.9 (2.2–3.8) and 3.5 (2.4–5.1) for men and women, respectively.

Conclusions: AF was found to be an independent risk factor for stroke and total cardiovascular mortality even in individuals without other TCVRFs.

Age-Specific Impact of Atrial Fibrillation on Cardiovascular Mortality Among Japanese Men and Women (The Ibaraki Prefectural Health Study [IPHS])

The age-specific impact of atrial fibrillation (AF) on cardiovascular diseases remains unclear. A total of 90,629 participants who were from 40 to 79 years of age in 1993 were followed up until 2013 as part of the Ibaraki Prefectural Health Study. Hazard ratios for mortality stratified by gender and age groups were calculated using Cox's proportional hazards regression models. A total of 22,794 patients (11,329 men and 11,465 women) died during the follow-up period, including 6,684 patients who died of cardiovascular causes (2,951 men and 3,733 women). On multivariable analysis, participants with AF had an increased risk of cardiovascular-related mortality compared with those without AF. Among participants aged 40 to 64 years, the adjusted hazard ratios were 3.2 (95% confidence interval [CI] 2.0 to 5.3) for men and 7.1 (95% CI 3.2 to 16.0) for women; the corresponding adjusted hazard ratios among participants aged 65 to 79 years were 3.0 (95% CI 2.2 to 4.0) for men and 3.7 (95% CI 2.5 to 5.4) for women. No significant difference in hazard ratios between age groups was found for either gender. AF was significantly associated with all-cause mortality in each age and gender group; again, no significant difference in hazard ratios between the age groups was found in terms of AF. AF may be an independent risk factor for cardiovascular and all-cause mortalities regardless of age.

Effectiveness of Low-Dose Intravenous Fentanyl for Postoperative Headache Management After Neck Clipping of Ruptured Intracranial Aneurysms

BACKGROUND

After subarachnoid hemorrhage (SAH), headache management is often difficult owing to the need to use multiple analgesic drugs. Fentanyl is an opioid we can use after surgery, and it can decrease pain post SAH. The aim of this study was to investigate the effectiveness and safety of fentanyl for management of headache after SAH.

METHODS

Twenty-two patients who underwent surgical clipping for ruptured intracranial aneurysms and complained of severe headache after the surgery were enrolled. Among them, 9 patients were given fentanyl combined with other analgesic drugs. The numeric rating scale score and dietary intake were measured in the acute phase after the SAH.

RESULTS

The numeric rating scale scores were significantly lower in the fentanyl (+) group. The maximum numeric rating scale decreased to <5 points within 16.5 ± 2.9 days in the fentanyl (-) group and within 12.0 ± 2.6 days in the fentanyl (+) group. The median numeric rating scale decreased to <5 points over 14.0 ± 4.2 days in the fentanyl (-) group and >7.7 ± 3.8 days in the fentanyl (+) group. At day 14, the fentanyl (+) group showed significantly better dietary intake than that of the fentanyl (-) group.

CONCLUSIONS

Using fentanyl after surgical clipping for ruptured intracranial aneurysms might decrease headache and produce few adverse effects. Adequate headache control showed improved dietary intake after SAH.

Self-Reported Eczema in Relation with Mortality from Cardiovascular Disease in Japanese: the Japan Collaborative Cohort Study

Aim: Previous studies suggested a positive association between eczema and cardiovascular disease (CVD), probably through enhanced systemic inflammation. However, several studies reported null findings about eczema and CVD, so the evidence is still controversial.

Methods: We asked 85,099 participants (35,489 men and 49,610 women), aged 40 to 79 years, without a history of CVD or cancer at baseline between 1988 and 1990, to complete a lifestyle questionnaire, including information eczema frequency (seldom, sometimes or often).

Results: During the 6,389,818 person-years of follow-up, there were 1,174 deaths from coronary heart disease (CHD), 979 from heart failure, 366 from cardiac arrhythmia, 2,454 from total stroke, 1,357 from ischemic stroke, 1,013 from hemorrhagic stroke, and 201 from aortic aneurysm or dissection. The multivariable-adjusted model showed that individuals who “sometimes” or “often” had eczema had 0.82 (95%confidence interval (CI): 0.69–0.97) or 1.26 (95%CI: 1.01–1.56) times the risk of mortality from CHD, respectively, compared to those who “seldom” did. Individuals who “often” had 1.30 (95%CI: 1.05–1.61) times the risk of mortality from CHD, compared to those who “seldom or sometimes” did. There was no association of eczema with mortality from other CVD, or no interaction between eczema and sex or age, in relation to any CVD mortality risk.

Conclusions: Self-reported frequent eczema was associated with increased risk of mortality from CHD, but not other major CVD, in a Japanese general population. Since steroid usage was not considered, future studies should include it as a potential confounding factor.

Valproic acid attenuates the risk of acute respiratory failure in patients with subarachnoid hemorrhage

BACKGROUND

Valproic acid (VPA) has shown potent anti-inflammatory effect and attenuates acute lung injury.

AIM

To determine whether the use of VPA is associated with a decreased risk of acute respiratory failure (ARF) in patients with subarachnoid hemorrhage (SAH).

DESIGN

The Taiwan National Health Insurance Research Database was used to analyse all patients newly diagnosed with SAH from 2000 to 2010. The VPA users were matched for age, gender and index date in 1:2 ratios with randomly selected non-VPA users as a comparison group.

METHODS

Multivariate Cox regression was used to identify the predictors of ARF and to compare the incidence rates of ARF among SAH patients using and not using VPA.

RESULTS

The study cohort included 16 228 newly diagnosed SAH patients, from which 521 VPA users and 1042 matched non-VPA-exposed individuals were selected. In the VPA-treated cohort and the non-VPA-treated cohort, 117 and 289 patients developed ARF, respectively. Any use of VPA was associated with a 16% decreased risk of ARF requiring mechanical ventilation in 30-day tracking of the SAH patients (adjusted hazard ratio [HR], 0.840, 95% confidence interval [CI], 0.676-0.945). Age, sepsis and pneumonia were identified as independent predictors of ARF in patients with SAH. After stratification, VPA users showed a lower risk of ARF among SAH patients complicated with pneumonia compared with non-users of VPA (adjusted HR, 0.816, 95% CI, 0.652-0.921).

CONCLUSIONS

Any use of VPA was associated with a reduced risk of ARF in patients with SAH. VPA may be beneficial for decreasing the risk of pneumonia-induced ARF in patients with SAH.

Diagnosis of a subarachnoid hemorrhage with only mild symptoms using computed tomography in Japan

Background

Japan is currently an aging society, with a huge proportion of elderly citizens. Consequently, the incidence and severity of subarachnoid hemorrhage (SAH) is predicted to increase in the future. Computed tomography (CT) is very important in the initial diagnosis of SAH. The proportion of hospitals owning CT systems in Japan is around four times greater than the mean number of systems owned by hospitals in other countries belonging to the Organisation for Economic Co-operation and Development. Because CT is readily available in Japan, it follows that this technique, with its impressive diagnostic power, might be more in demand in Japan compared to other countries. However, misdiagnosis of SAH is a relatively common problem and is associated with increased mortality and morbidity, even in individuals who initially present in good condition.

Case presentation

We describe a patient with subtle clinical and CT signs of SAH. A 39-year-old Japanese man visited our hospital with a 3-day history of mild headache, shoulder stiffness, and a feeling of dizziness. His physical examination was normal aside from mild neck stiffness. Although CT did not reveal obvious abnormalities, we noticed subtle signs of SAH on CT images, which have been observed in SAH patients with mild symptoms. Thus, we diagnosed our patient with SAH and provided appropriate treatment (aneurysm clipping). Following this, the patient progressed without development of the initial complications, and he was subsequently discharged from our hospital without sequela.

Conclusion

Thus, physicians should be able to recognize subtle characteristics of CT imaging in case of SAH patients with low grade symptoms, as this can facilitate early diagnosis.

Independent Prognostic Value of Single and Multiple Non-Specific 12-Lead Electrocardiographic Findings for Long-Term Cardiovascular Outcomes: A Prospective Cohort Study

Aims

The long-term prognostic effect of non-specific 12-lead electrocardiogram findings is unknown. We aimed to evaluate the cumulative prognostic impact of axial, structural, and repolarization categorical abnormalities on cardiovascular death, independent from traditional risk scoring systems such as the Framingham risk score and the NIPPON DATA80 risk chart.

Methods and Results

A total of 16,816 healthy men and women from two prospective, longitudinal cohort studies were evaluated. 3,794 (22.6%) individuals died during a median follow-up of 15 years (range, 2.0–24 years). Hazard ratios for cardiovascular death, all-cause death, coronary death and stroke death were calculated for the cumulative and independent axial, structural, and repolarization categorical abnormalities adjusted for the Framingham risk score and the NIPPON DATA80 risk chart. Individuals with two or more abnormal categories had a higher risk of cardiovascular death after adjustment for Framingham risk score (men: HR 4.27, 95%CI 3.35–5.45; women: HR 4.83, 95%CI 3.76–6.22) and NIPPON DATA80 risk chart (men: HR 2.39, 95%CI 1.87–3.07; women: HR 2.04, 95%CI 1.58–2.64).

Conclusion

Cumulative findings of axial, structural, and repolarization abnormalities are significant predictors of long-term cardiovascular death in asymptomatic, healthy individuals independent of traditional risk stratification systems.

Surveillance and Measuring Trends of Stroke in Japan: The Takashima Stroke Registry (1988 – Present)

The Takashima Stroke Registry is a disease registration system for stroke established in Japan in 1988. This stroke registry is a population-based, prospective, observational study whose objective is to monitor trends in the incidence and case-fatality of stroke in Japan. Takashima County is located in the rural area of the Shiga prefecture in central Japan, having a stable population of approximately 54,000. It is a farming community with similar cultural values and standards of living throughout the region. The population has remained fairly stable during the 16-year study period. 1750 stroke cases (men 937 and women 813) were registered during 1988–2002. The average ages of the men and women patients were 69.4 and 74.4 years respectively. Stroke diagnostic criteria are established for the Monitoring System for Cardiovascular Disease commissioned by the Ministry of Health and Welfare, Japan. These criteria were based on WHO-MONICA project. Takashima registry system was planned to capture all the cases in the study area by covering all the hospitals of the county. To ensure that eligible patients hospitalized outside the county were not omitted, registration procedures were also conducted at three high-level medical facilities within the Shiga region but outside the county. Due to the high rate of computed tomography use in Japan the identification of stroke cases within the study area is almost complete and stroke diagnosis and classification are accurately recorded.

miRNA expression profiling of cerebrospinal fluid in patients with aneurysmal subarachnoid hemorrhage

OBJECTIVE MicroRNAs (miRNAs) regulate gene expression and therefore play important roles in many physiological and pathological processes. The aim of this pilot study was to determine the feasibility of extraction and subsequent profiling of miRNA from CSF samples in a pilot population of aneurysmal subarachnoid hemorrhage patients and establish if there is a distinct CSF miRNA signature between patients who develop cerebral vasospasm and those who do not. METHODS CSF samples were taken at various time points during the clinical management of a subset of SAH patients (SAH patient samples without vasospasm, n = 10; SAH patient samples with vasospasm, n = 10). CSF obtained from 4 patients without SAH was also included in the analysis. The miRNA was subsequently isolated and purified and then analyzed on an nCounter instrument using the Human V2 and V3 miRNA assay kits. The data were imported into the nSolver software package for differential miRNA expression analysis. RESULTS From a total of 800 miRNAs that could be detected with each version of the miRNA assay kit, a total of 691 miRNAs were communal to both kits. There were 36 individual miRNAs that were differentially expressed (p < 0.01) based on group analyses, with a number of miRNAs showing significant changes in more than one group analysis. The changes largely reflected differences between non-SAH and SAH groups. These included miR-204-5p, miR-223-3p, miR-337-5p, miR-451a, miR-489, miR-508-3p, miR-514-3p, miR-516-5p, miR-548 m, miR-599, miR-937, miR-1224-3p, and miR-1301. However, a number of miRNAs did exclusively differ between the vasospasm and nonvasospasm SAH groups including miR-27a-3p, miR-516a-5p, miR-566, and miR-1197. CONCLUSIONS The findings indicate that temporal miRNA profiling can detect differences between CSF from aneurysmal SAH and non-SAH patients. Moreover, the miRNA profile of CSF samples from patients who develop cerebral vasopasm may be distinguishable from those who do not. These results provide a foundation for future research at identifying novel CSF biomarkers that might predispose to the development of cerebral vasospasm after SAH and therefore influence subsequent clinical management.

Bowel Movement Frequency, Laxative Use, and Mortality From Coronary Heart Disease and Stroke Among Japanese Men and Women: The Japan Collaborative Cohort (JACC) Study

Background

The associations of bowel movement frequency and laxative use with cardiovascular disease (CVD) are unclear.

Methods

A total of 72 014 subjects (29 668 men and 42 346 women) aged 40 to 79 years, without a history of CVD or cancer, completed a lifestyle questionnaire at baseline between 1988 and 1990 that included information on bowel movement frequency (daily, every 2–3 days, or once every 4 or more days) and laxative use (yes or no), and were followed-up until 2009.

Results

During the subjects’ 1 165 569 person-years of follow-up, we documented 977 deaths from coronary heart disease (561 men and 416 women), 2024 from total stroke (1028 men and 996 women), 1127 from ischemic stroke (606 men and 521 women), and 828 from hemorrhagic stroke (388 men and 440 women). The prevalence of CVD risk factors, such as diabetes, stress, depression, and physical inactivity, was higher in laxative users and in those with a lower frequency of bowel movements. The multivariable HRs (95% confidence intervals [CIs]) of laxative users were as follows: 1.56 (95% CI, 1.21–2.03) for coronary heart disease and 1.37 (95% CI, 1.07–1.76) for ischemic stroke in men, and 1.27 (95% CI, 1.08–1.49) for total stroke, and 1.45 (95% CI, 1.17–1.79) for ischemic stroke in women. Similar results were observed even after the exclusion of deaths that occurred early in the follow-up period. A significant association between bowel movement frequency and mortality from CVD was not observed.

Conclusions

Constipation could be a marker of exposure to CVD risk factors, and laxative use could be a risk factor for mortality from coronary heart disease and ischemic stroke.

One-year case fatality rate following stroke in the Mashhad Stroke Incidence Study: a population-based study of stroke in Iran

Background

In developing countries, there are few comprehensive studies of mortality following stroke.

Aims and/or hypothesis

We aimed to determine the one-year case fatality rate following stroke and to identify factors associated with death in a population-based stroke incidence study in Iran.

Methods

Six hundred eighty-four patients who had suffered a stroke between November 21, 2006, and November 20, 2007, and were recruited to the Mashhad Stroke Incidence Study were followed up at one-year. Most patients were seen in an outpatient visit. When patients had died, a verbal autopsy was conducted by telephone with the next of kin.

Results

A total of 226 (34.3%) patients died during the first year following stroke. The cumulative one-year case fatality rate was 30.6% following ischemic stroke and 53.0% following hemorrhagic stroke (55.8% after intracerebral hemorrhage and 35.7% after subarachnoid hemorrhage). The majority of these deaths occurred in the first 28 days after stroke (17.7% with ischemic and 43.0% with hemorrhagic stroke). Factors associated with greater mortality at one-year (excluding those who died during the first week) were hemorrhagic stroke [hazard ratio (HR) 3.99; 95% confidence interval 1.90-8.37], age (HR 1.05; 95% confidence interval 1.03-1.08), previous transient ischemic attack (HR 2.45; 95% confidence interval 1.00-5.99), and National Institutes of Health Stroke Scale on admission (HR 1.14; 95% confidence interval 1.10-1.17).

Conclusion

Despite the younger age of stroke occurrence in Iran, the one-year case fatality rate following stroke is similar to that reported in developed countries.

Association of measles and mumps with cardiovascular disease: The Japan Collaborative Cohort (JACC) study

OBJECTIVE

Although it has been suggested that exposure to infections during childhood could decrease risk of atherosclerotic cardiovascular disease (CVD), the evidence is scarce. We investigated the association of measles and mumps with CVD.

METHODS

43,689 men and 60,147 women aged 40-79 years at baseline (1988-1990) completed a lifestyle questionnaire, including their history of measles and mumps, and were followed until 2009. Histories of infections were categorized as having no infection (reference), measles only, mumps only, or both infections. Hazard ratios (HR) for mortality from CVD across histories of infections were calculated.

RESULTS

Men with measles only had multivariable HR (95% confidence interval) of 0.92 (0.85-0.99) for total CVD, those with mumps only had 0.52 (0.28-0.94) for total stroke and 0.21 (0.05-0.86) for hemorrhagic stroke, and those with both infections had 0.80 (0.71-0.90) for total CVD, 0.71 (0.53-0.93) for myocardial infarction, and 0.83 (0.69-0.98) for total stroke. Women with both infections had 0.83 (0.74-0.92) for total CVD and 0.84 (0.71-0.99) for total stroke. We also compared subjects with measles only or mumps only (reference) and those with both infections. Men with both infections had 0.88 (0.78-0.99) for total CVD. Women with both infections had 0.85 (0.76-0.94) for total CVD, 0.79 (0.67-0.93) for total stroke, 0.78 (0.62-0.98) for ischemic stroke and 0.78 (0.62-0.98) for hemorrhagic stroke.

CONCLUSIONS

Measles and mumps, especially in case of both infections, were associated with lower risks of mortality from atherosclerotic CVD.

Alcohol consumption, hospitalization and medical expenditure: a large epidemiological study on the medical insurance system in Japan

AIMS

This study investigated the relationship between alcohol drinking habits and the onset of high medical expenditure in a Japanese male population.

METHODS

The cohort comprised 94,307 male beneficiaries 40-69 years of age of the Japanese medical insurance system, who had daily alcohol drinking habits. The likelihood of incurring high medical expenditure, defined as the ≥90th percentile of the medical expenditure distribution in the study population 1 year after baseline, as well as the likelihood of undergoing hospitalization that year were compared among the participants grouped according to their alcohol consumption amount (<2, 2-3.9, 4-5.9, ≥6 drinks/day).

RESULTS

Participants who ranked in the top 10% medical expenditure group within the 1 year after baseline each incurred at least 2152 euros/year. The top 10% medical expenditure group accounted for 61.1% of the total medical expenditure in the study population. The odds ratios (95% confidence intervals) for ranking in the top 10% group during the 1-year period, compared with the <2 drinks (23 g of alcohol)/day group, were 1.08 (1.02-1.15) for 2-3.9 drinks/day, 1.11 (1.05-1.19) for 4-5.9 drinks/day, and 1.31 (1.18-1.45) for ≥6 drinks/day after adjustment for age, body mass index, and smoking and exercise habits. The adjusted odds ratios for undergoing hospitalization were 1.11 (1.04-1.19), 1.14 (1.06-1.24) and 1.39 (1.24-1.56), respectively.

CONCLUSION

The likelihood of incurring high medical expenditure and undergoing hospitalization increased with daily alcohol consumption amount.

Risk factors and 30-day case fatality of first-ever stroke in Basrah, Iraq

Background:

The aim of this hospital-based study is to determine the types, the frequency of risk factors and the 30-day case fatality of first-ever stroke in Basrah, Iraq.

Materials and Methods:

This was a hospital-based prospective study between January 2008 and July 2008 in Basrah, Iraq. Two hundred twenty-five (225) patients, who were admitted for first-ever stroke to the four major hospitals in Basrah, were interviewed and followed up for 30 days. Risk factors studied were smoking, history of diabetes mellitus, hypertension, atrial fibrillation, ischaemic heart diseases and transient ischaemic attack.

Results:

The mean age of the studied subjects was 63.8 ± 12.3 years. Males constituted 56% of cases. Clinical types of stroke were ischaemic stroke (83.6%), intracerebral haemorrhage (16%) and subarachnoid haemorrhage (0.4%). The prevalence of risk factors was; hypertension (66.2%), family history of stroke (31.6%), ischaemic heart diseases (28.9%), smoking (28.4%), diabetes mellitus (28%), transient ischaemic attack (10.2%), atrial fibrillation (9.8%) and heart failure (5.8%). The 30-day case fatality rate was 22.7%.

Conclusions:

Ischaemic stroke was the highly prevalent type. Hypertension, family history of stroke, ischaemic heart diseases, smoking and diabetes mellitus were the major risk factors of first ever stroke in Basrah. The 30-day case fatality rate of stroke in Basrah was nearly similar to that in western countries, but higher than that reported in the neighbouring Arab countries. Early detection of modifiable risk factors that can prevent stroke or at least minimise its complications is highly recommended.

Smoking and hemorrhagic stroke mortality in a prospective cohort study of older Chinese

BACKGROUND AND PURPOSE

Hemorrhagic stroke is more common in non-Western settings and does not always share risk factors with other cardiovascular diseases. The association of smoking with hemorrhagic stroke subtypes has not been established. We examined the association of cigarette smoking with hemorrhagic stroke, by subtype (intracerebral hemorrhage and subarachnoid hemorrhage), in a large cohort of older Chinese from Hong Kong.

METHODS

Multivariable Cox regression analysis was used to assess the adjusted associations of smoking at baseline with death from hemorrhagic stroke and its subtypes, using a population-based prospective cohort of 66 820 Chinese aged>65 years enrolled from July 1998 to December 2001 at all the 18 Elderly Health Centers of the Hong Kong Government Department of Health and followed until May 31, 2012.

RESULTS

After follow-up for an average of 10.9 years (SD=3.1), 648 deaths from hemorrhagic stroke had occurred, of which 530 (82%) were intracerebral hemorrhage. Current smoking was associated with a higher risk of hemorrhagic stroke (hazard ratio, 2.19; 95% confidence interval, 1.49-3.22), intracerebral hemorrhage (1.94; 1.25-3.01), and subarachnoid hemorrhage (3.58; 1.62-7.94), adjusted for age, sex, education, public assistance, housing type, monthly expenditure, alcohol use, and exercise. Further adjustment for hypertension and body mass index slightly changed the estimates.

CONCLUSIONS

Smoking is strongly associated with hemorrhagic stroke mortality, particularly for subarachnoid hemorrhage.

Statin use and risk of cerebral aneurysm rupture: a hospital-based case-control study in Japan

BACKGROUND

Recent reports have showed that some statins have protective effects in experimental cerebral aneurysm models. We conducted a case-control study to investigate an association between statin use and the rupture risk of cerebral aneurysm in Japanese population.

METHODS

This was a multihospital case-control study; cases and controls were collected from 15 hospitals in Japan. Cases consisted of patients with aneurysmal subarachnoid hemorrhage hospitalized from April 2009 to March 2011. Controls were selected from patients who had newly diagnosed unruptured saccular aneurysms from April 2006 to March 2011. The primary exposure of interest was statin use. Multivariable logistic regression was used to assess the relationship between stain use and the rupture risk of cerebral aneurysm.

RESULTS

A total of 117 cases and 304 controls were included in the analyses. Statin was used in 9.4% of cases and 26.0% of controls. Controls had a significantly higher rate of use of statin. The use of any statin was associated with cerebral aneurysm rupture after adjustment of potential confounders (adjusted odds ratio: .30, 95% confidence interval: .14-.66). The association was similar in each stratum of total cholesterol level.

CONCLUSIONS

This observation from a hospital-based case-control study in Japan suggested that there is inverse relationship between use of statins and cerebral aneurysm rupture. Future clinical studies are needed.

Incidence of nontraumatic osteonecrosis of the femoral head in the Japanese population

OBJECTIVE

To estimate the incidence rate of nontraumatic osteonecrosis of the femoral head (ONFH) in the Japanese population.

METHODS

A survey was conducted to ascertain newly identified patients with nontraumatic ONFH in the Specified Disease Treatment Research Program of Fukuoka Prefecture (population 5 million) between 1999 and 2008. Distributions of age and sex in this population were investigated. Crude incidence rates of nontraumatic ONFH were calculated, and age-adjusted incidence rates were estimated by adjusting the crude values against those for the Japanese standard population in each year.

RESULTS

In Fukuoka Prefecture, 1,244 newly identified patients with nontraumatic ONFH were recruited into the Japanese subsidy program over the span of 10 years. The ratio of men to women was 1.6, comprising 758 men (61%; mean age 48 years) and 486 women (39%; mean age 56 years). The crude incidence rate of nontraumatic ONFH in the 10-year period was 2.58 cases per 100,000 person-years (range 1.54-3.66). The mean age-adjusted incidence rate was 2.51 cases per 100,000 person-years.

CONCLUSION

This study showed that the incidence rate of nontraumatic ONFH was 2.51 cases per 100,000 person-years in the Japanese population.

Is there any circadian variation consequence on acute case fatality of stroke? Takashima Stroke Registry, Japan (1990-2003)

BACKGROUND

Circadian periodicity in the onset of stroke has been reported. However, it is unclear whether this variation affects the acute stroke case fatality. Time of the day variation in stroke case fatality was examined using population-based stroke registration data.

METHODS

Stroke event data were acquired from the Takashima Stroke Registry, which covers a stable population of approximately 55,000 in Takashima County in central Japan. During the period of 1990-2003, there were 1080 (549 men and 531 women) cases with classifiable stroke onset time. Stroke incidence was categorized as occurring at night (midnight-6 a.m.), morning (6 a.m.-noon), afternoon (noon-6 p.m.), and evening (6 p.m.-midnight). The 28-day case fatality rates and 95% confidence intervals (95% CI) were calculated by gender, age, and stroke subtype across the time blocks. After adjusting for gender, age at onset, and stroke severity at onset, the hazard ratios for fatal strokes in evening, night, and morning were calculated, with afternoon serving as the reference.

RESULTS

For all strokes, the 28-day case fatality rate was 23.3% (95% CI:19.4-27.6) for morning onset, 16.9% (95% CI:13.1-21.6) for afternoon onset, 18.3% (95% CI:13.6-24.1) for evening onset, and 21.0% (95% CI:15.0-28.5) for the night onset stroke. The case fatality for strokes during the morning was higher than the case fatality for strokes during afternoon. This fatality risk excess for morning strokes persisted even after adjusting for age, gender, and stroke severity on onset in multivariate analysis.

CONCLUSION

In the examination of circadian variation of stroke case fatality, 28-day case fatality rate tended to be higher for the morning strokes.

Mild retinopathy is a risk factor for cardiovascular mortality in Japanese with and without hypertension: the Ibaraki Prefectural Health Study

BACKGROUND

It is unclear whether mild hypertensive retinopathy is a risk factor for mortality. This study examined whether mild hypertensive retinopathy could be a risk factor for cardiovascular mortality in subjects with and without hypertension.

METHODS AND RESULTS

In this cohort study, 87 890 individuals (29 917 men and 57 973 women) 40 to 79 years of age in 1993 were followed up until 2008. Retinal photography was classified as normal, grade 1, or grade 2 based on the Keith-Wagener-Barker system. Risk ratios for all-cause and cause-specific mortality for each classification were calculated with Cox proportional hazards regression models. Covariates included age, systolic blood pressure, antihypertensive medication use, and other cardiovascular risk factors. Multivariable hazard ratios for total cardiovascular disease mortality were 1.24 (95% confidence interval [CI], 1.12-1.38) and 1.23 (95% CI, 1.03-1.47) for grades 1 and 2 among men and 1.12 (95% CI, 1.01-1.24) and 1.44 (95% CI, 1.24-1.68) for grades 1 and 2 among women, respectively. Hazard ratios for total stroke mortality were 1.31 (95% CI, 1.13-1.53) and 1.38 (95% CI, 1.08-1.77) for grades 1 and 2 among men and 1.30 (95% CI, 1.12-1.50) and 1.70 (95% CI, 1.36-2.11) for grades 1 and 2 among women, respectively. For both hypertensive and normotensive subjects of each sex, multivariable hazard ratios for all-cause mortality, total cardiovascular mortality, and total stroke mortality were significantly higher for grade 1 or 2 compared with normal.

CONCLUSIONS

Mild hypertensive retinopathy is a risk factor for cardiovascular mortality independently of cardiovascular risk factors among men and women with and without hypertension.

Acute lung injury associated with systemic inflammatory response syndrome following subarachnoid hemorrhage: a survey by the Shonan Neurosurgical Association

Acute lung injury (ALI) associated with systemic inflammatory response syndrome (SIRS) is a systemic complication following subarachnoid hemorrhage (SAH), but the incidence and influence on prognosis are unclear. The incidences of SIRS and ALI were surveyed in a prospective multicenter study of 96 patients admitted for SAH between December 2004 and June 2007. Hunt and Hess grade and Glasgow Outcome Scale score were also investigated. Forty-eight patients were diagnosed with SIRS, and 26 developed ALI within 4 weeks of admission. Nineteen of the 26 patients with ALI were complicated by SIRS, and 7 developed only ALI. Thirteen of the 19 patients complicated by SIRS and ALI died, and this mortality was higher than for patients with only SIRS (3/29) and only ALI (1/7). Multivariate analysis of the development of SIRS and/or ALI and Hunt and Hess grade as risk factors associated with aggravation of the outcome showed that complication with SIRS and ALI had the highest risk. Half of the patients admitted for SAH developed SIRS, and more than 25% developed ALI. The prognosis for patients complicated by SIRS and ALI was poor, which indicates that prevention and active treatment of these two pathologies are important.

Lifetime risk of stroke and impact of hypertension: estimates from the adult health study in Hiroshima and Nagasaki

Very few reports have been published on lifetime risk (LTR) of stroke by blood pressure (BP) group. This study included participants in the Radiation Effects Research Foundation Adult Health Study who have been followed up by biennial health examinations since 1958. We calculated the LTR of stroke for various BP-based groups among 7847 subjects who had not been diagnosed with stroke before the index age of 55 years using cumulative incidence analysis adjusting for competing risks. By 2003, 868 subjects had suffered stroke (512 (58.9%) were women and 542 (62.4%) experienced ischemic stroke). BP was a significant factor in determining risk of stroke for men and women, with distributions of cumulative risk for stroke significantly different across BP groups. The LTR of all-stroke for normotension (systolic BP/diastolic BP < 120/80 mm Hg), prehypertension (120-139/80-89 mm Hg), stage 1 hypertension (140-159/90-99 mm Hg) and stage 2 hypertension (> 160/100 mm Hg) were 13.8-16.9-25.8-25.8% in men and 16.0-19.9-24.0-30.5% in women, respectively (P < 0.001 among BP groups in both sexes). The estimates did not differ significantly (P = 0.16) between normotensive and prehypertensive subjects. One in five Japanese atomic bomb survivor subjects experienced stroke over their lifetime from the age of 55 years. Long-term stroke risks were elevated in those with hypertension (> 140/90 mm Hg) at any of the index ages of 45, 55, 65 and 75 years.

Lifetime Risk of Stroke in Japan

Background and Purpose— Lifetime risk (LTR) is an epidemiologic measure that expresses the probability of disease in the remaining lifetime for an index age. The LTR for stroke has not been reported for the Japanese population.

Methods— We included all participants from the Suita Study who were cardiovascular disease–free at baseline. Age (in years) was used as the time scale. Age-specific stroke incidence and all-cause mortality were calculated with the person-year method, and we estimated the sex- and index age–specific LTRs of first-ever stroke and its subtypes, taking into account the competing risk of death.

Results— We followed up 5498 participants from 1989 to 2005 for a total of 67 475 person-years. At age 55 years, the LTR for stroke, after accounting for competing risks of death, was 18.3% for men and 19.6% for women. The LTR for cerebral infarction was 14.6% for men and 15.5% for women, and the LTR for intracerebral hemorrhage was 2.4% for men and 1.4% for women at the index age of 55 years. The LTR for stroke remained similar across other index ages of 45, 55, and 65 years.

Conclusions— The observed probabilities illustrate that ≈1 in 5 men and women of middle age will experience stroke in their remaining lifetime. This easy understandable information can be used as an important index to assist in public health education and planning.

Dietary folate and vitamin b6 and B12 intake in relation to mortality from cardiovascular diseases: Japan collaborative cohort study

BACKGROUND AND PURPOSE

The association of dietary folate and B vitamin intakes with risk of cardiovascular disease is controversial, and the evidence in Asian populations is limited.

METHODS

A total of 23 119 men and 35 611 women, age 40 to 79 years, completed a food frequency questionnaire in the Japan Collaborative Cohort Study. During the median 14-year follow-up, there were 986 deaths from stroke, 424 from coronary heart disease, and 2087 from cardiovascular disease.

RESULTS

Dietary folate and vitamin B(6) intakes were inversely associated with mortality from heart failure for men and with mortality from stroke, coronary heart disease, and total cardiovascular disease for women. These inverse associations did not change materially after adjustment for cardiovascular risk factors. No association was found between vitamin B(12) intake and mortality risk.

CONCLUSIONS

High dietary intakes of folate and vitamin B(6) were associated with reduced risk of mortality from stroke, coronary heart disease, and heart failure among Japanese.

Trend of Stroke Incidence in a Japanese Population: Takashima Stroke Registry, 1990-2001

Background

In Japan, stroke mortality and incidence started to decline during the 1960s. The recent unfavourably diverging trends in risk factors make it uncertain whether the decline will continue. Few comprehensive stroke registries of long research duration exist in Japan to illustrate the trends in stroke incidence.

Objective

We examined 12-year stroke registration data to evaluate the current trend in a Japanese population.

Methods

Data were obtained from the Takashima Stroke Registry, covering approximately 55000 residents of Takashima County in central Japan. We calculated the age-adjusted stroke incidence rates (/100 000 person-years) and 95% confidence intervals for 1990–1992, 1993–1995, 1996–1998, and 1999–2001. We applied the direct method to adjust for the age distribution among the four periods. The incidence time trend was determined by calculating the average annual change across the study years using negative binomial regression analysis.

Results

There were 1453 (men: 771 and women: 682) registered first-ever stroke cases during 1990–2001. The diagnosis was established by neuro-imaging in 93·6% of the cases. The average age was 69·4 years in men and 74·2 years in women. The age-adjusted incidence rates of stroke across the four observation periods were 143·1 (confidence interval: 127·4-158·8) in 1990–1992, 147·4 (confidence interval: 131·9–162·8) in 1993–1995, 120·4 (confidence interval: 106·7–134·0) in 1996–1998, and 122·9 (confidence interval: 109·6–136·2) in 1999–2001. The stroke incidence across the study years showed an insignificant time trend, with an average annual change of −0·33% (confidence interval: −2·44 to 1·78) per year. Similar trends were observed for both men and women and stroke subtypes.

Conclusions

The previously reported declining trend in stroke incidence may have levelled off or slowed down considerably in the Japanese population.

Associations between metabolic syndrome and mortality from cardiovascular disease in Japanese general population, findings on overweight and non-overweight individuals. Ibaraki Prefectural Health Study

BACKGROUND

The impact of being overweight, as a component of the metabolic syndrome (MetS), for cardiovascular disease (CVD) mortality was investigated and compared with the predictive value of MetS by 2 different definitions.

METHODS AND RESULTS

A 12-year prospective study of 30,774 Japanese men and 60,383 women aged 40-79 years was conducted. The multivariate hazard ratio (HR; 95% confidence interval) of total CVD mortality for overweight subjects with >or=2 additional risk factors with reference to subjects with 0 of 4 MetS components was 1.83 (1.41-2.38) for men and 1.90 (1.45-2.49) for women, and for non-overweight subjects with >or=2 additional risk factors 1.75 (1.38-2.24) and 1.97 (1.52-2.55), respectively. The proportion of excess CVD deaths in the latter group was 1.5-fold higher than that in the former group. Multivariate HRs of coronary heart disease and total CVD mortality for MetS by the modified criteria of the American Heart Association/National Heart, Lung, and Blood Institute were 1.62 (1.31-2.00) and 1.23 (1.09-1.39), respectively, for men and 1.32 (1.05-1.65) and 1.12 (1.00-1.25), respectively, for women. The respective HRs for MetS by the International Diabetic Federation definition did not reach statistical significance, except for coronary heart disease in men.

CONCLUSIONS

Non-overweight individuals with metabolic risk factors, as well as overweight individuals with such factors, should be targeted to reduce the CVD burden in the general population.

Japan Arteriosclerosis Longitudinal Study-Existing Cohorts Combine (JALS-ECC): rationale, design, and population characteristics

BACKGROUND

The Japan Arteriosclerosis Longitudinal Study-Existing Cohorts Combine (JALS-ECC) is a pooled study based on individual participant data from existing prospective cohort studies in Japan. Its purpose was to consider associations between risk factors and cardiovascular disease (CVD) outcomes, as well as differences between subgroups, defined by age, gender or geographical region, which could not be detected in the smaller samples.

METHODS AND RESULTS

Individual records for 66,691 participants in 21 cohort studies were pooled, accounting for a total of 575,628 person-years. From this data, there were 409 deaths attributed to stroke and 169 deaths attributed to coronary heart disease (CHD). Total stroke and CHD events were 1,478 and 178, respectively. Of the 1,424 total stroke events with a reported stroke subtype, 975 were classified as ischemic, 267 as hemorrhagic, and 178 as subarachnoid hemorrhage.

CONCLUSION

The JALS-ECC collected data from existing cohort studies covering a diverse Japanese population, which has provided information about the effects of modifiable factors on the risks of the CVD. Such information should provide a reliable basis for establishing prevention strategies.

Baseline cardiovascular risk factors and stroke mortality by municipality population size in a 19-year follow-up study-NIPPON DATA80

The urban-rural difference in cardiovascular risk factors and stroke mortality throughout Japan was examined in a cohort by using hierarchical data structure. The subjects were 9,309 men and women aged ≥ 30 years who were residents of 294 areas in 211 municipalities of Japan in 1980; they were followed up until 1999. The population sizes of the municipalities in which the aforementioned areas were located were used to distinguish between urban and rural areas. We applied multilevel modeling to take into account the hierarchical data structure of individuals (subjects) (level 1) nested within areas (level 2). Statistically significant differences were observed in the case of medium (30,000-300,000) and small (<30,000) municipality populations compared with large (≥300,000) municipality populations with regard to the following parameters: body mass index in men, serum total cholesterol in both men and women, and daily alcohol drinking in women. The values or frequencies of these cardiovascular risk factors were significantly higher in large populations. Meanwhile, age-adjusted odds ratios for stroke mortality in the areas in the medium and small municipalities compared with those in the areas in the large municipalities were 1.31 (95% confidence interval (CI) 0.81-2.13) and 1.40 (95% CI 0.87-2.24) in men, and 1.32 (95% CI 0.79-2.20) and 1.62 (95% CI 0.99-2.65) in women, respectively. The results of multivariate analyses adjusted for age, body mass index, total cholesterol, diabetes, hypertension, current smoking, and daily alcohol consumption did not change materially. In conclusion, stroke mortality tended to be higher in rural areas than in urban areas in Japan, especially among women.

Incidence of total stroke, stroke subtypes, and myocardial infarction in the Japanese population: the JMS Cohort Study

Background

Previous reports indicated that the incidence rate of stroke was higher in Japan than in Western countries, but the converse was true in the case of myocardial infarction (MI). However, few population-based studies on the incidence rates of stroke and MI have been conducted in Japan.

Methods

The Jichi Medical School (JMS) Cohort Study is a multicenter population-based cohort study that was conducted in 12 districts in Japan. Baseline data were collected between April 1992 and July 1995. We examined samples from 4,869 men and 7,519 women, whose mean ages were 55.2 and 55.3 years, respectively. The incidence of stroke, stroke subtypes, and MI were monitored.

Results

The mean follow-up duration was 10.7 years. A total of 229 strokes and 64 MIs occurred in men, and 221 strokes and 28 MIs occurred in women. The age-adjusted incidence rates (per 100,000 person-years) of stroke were 332 and 221 and those of MI were 84 and 31 in men and women, respectively. In the case of both sexes, the incidence rates of stroke and MI were the highest in the group of subjects aged > 70 years.

Conclusion

We reported current data on the incidence rates of stroke and MI in Japan. The incidence rate of stroke remains high, considerably higher than that of MI, in both men and women. The incidence rates of both stroke and MI were higher in men than in women.

Prognostic implications of left ventricular wall motion abnormalities associated with subarachnoid hemorrhage

Left ventricular (LV) dysfunction generally occurs early in the course of subarachnoid hemorrhage (SAH). We evaluated the prognostic value of electrocardiographic (ECG) abnormalities and echocardiographic LV dysfunction evaluated shortly after SAH. We prospectively enrolled 47 SAH patients (62 +/- 14 years, mean +/- SD) who were admitted to the neurosurgical care unit of our institute. Neurological status was rated on the day of admission. Twelve-lead ECG and 2-dimensional echocardiography were recorded 2 +/- 1 day after onset of SAH. ECG abnormalities (pathological Q-wave, ST-segment deviation, T-wave inversion, and QT prolongation) were evaluated and the incidences of global (LV ejection fraction < 50%) and segmental (regional wall motion abnormality [RWMA]) LV dysfunction were measured. During a follow-up period of 44 +/- 23 days, 17 (36%) patients died. ECG abnormalities, LV ejection fraction < 50%, and RWMA were observed in 62%, 11%, and 28% of patients, respectively. Univariate Cox proportional hazards regression analysis revealed that neurological status, rate-corrected QT interval, LV ejection fraction, and RWMA were significant predictors of death. After adjustment for these significant clinical variables, and age and sex, independent predictors of mortality were neurological status and RWMA. RWMA may provide significant prognostic information in patients with SAH.

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

Japan's age-adjusted rate for mortality from stroke increased after the Second World War until 1965 and then showed a significant decline until 1990; however, the age-adjusted rate for mortality from all heart disease and coronary heart disease (CHD) increased until 1970 and then declined slowly. A puzzling question is why the rate of mortality from CHD declined in spite of an increase in serum total cholesterol level following an increase in fat consumption. It was confirmed that CHD incidence was far lower in several Japanese populations compared to Western countries in the " Monitoring Trends and Determinants in Cardiovascular Disease " (MONICA) project; therefore, the lower CHD mortality in Japan stems from the lower CHD incidence. CHD risk factors based on epidemiologic cohort studies in Japan were no different from those of other industrialized countries: hypertension, hypercholesterolemia, smoking and diabetes mellitus (DM). So, how can we explain this phenomenon?There are three possible explanations. One is the decline in population blood pressure level and the prevalence of hypertension during the years 1965-1990; the second is the decline in smoking rate in men and women; the third is that the serum total cholesterol level for middle-aged and elderly populations remains 5-15 mg/dL lower than that of the US elderly counterpart, although men aged 40-49 in Japan and the US had similar serum total cholesterol levels. It was also noted that elderly people in Japan, as observed in the Seven Countries Study, had far lower serum total cholesterol levels in midlife, i.e., around 160 mg/dL in the 1960s. This was not the case for elderly in the US where a higher serum total cholesterol level was observed in midlife. In conclusion, the lower serum cholesterol level in the past of Japanese middle-aged and elderly people compared to Western counterparts helps to maintain the low CHD incidence and mortality supported by the declining trend in blood pressure level and smoking rate for both men and women.

Serum total cholesterol levels and risk of mortality from stroke and coronary heart disease in Japanese: The JACC study

The relation between serum total cholesterol and coronary heart disease is well established, but the relations with total stroke and stroke subtypes are controversial. We conducted a nested case-control study as part of the JACC study. A total of 39,242 subjects, 40-79 years of age, provided serum samples at baseline between 1988 and 1990. During the 10-year follow-up, 345 deaths from total strokes (including 76 intraparenchymal hemorrhages) and 150 deaths from coronary heart diseases were recorded. The control subjects were matched for sex, age, community, and year of serum storage, and further adjusted for systolic blood pressure, high density lipoprotein (HDL)-cholesterol, ethanol intake category, smoking status, and diabetes. Serum total cholesterol levels were measured using an enzymatic method. Cases with total stroke and more specifically intraparenchymal hemorrhage had lower mean values of serum total cholesterol levels compared with control subjects. The risk of mortality from intraparenchymal hemorrhage was significantly higher for persons with low total cholesterol levels [less than 4.14 mmol/l (160 mg/dl)] than with those with higher levels. The risk of mortality from coronary heart disease for persons with serum total cholesterol levels more than or equal to 6.72 mmol/l (260 mg/dl) was significantly higher than those with levels less than 4.14 mmol/l (160 mg/dl). Low serum total cholesterol levels are associated with high mortality from intraparenchymal hemorrhage while high levels are associated with high mortality from coronary heart disease among Japanese.

Urban–rural difference in stroke mortality from a 19-year cohort study of the Japanese general population: NIPPON DATA80

In Japan, cohort studies on stroke have been mainly conducted in rural areas, with few studies comparing stroke mortality between urban and rural areas. We aimed to explore urban-rural difference in stroke mortality throughout Japan using a representative sample of the general Japanese population, the NIPPON DATA80. This study included 9309 subjects (4080 men and 5229 women) aged 30 years or older who were residents of 294 areas in 211 municipalities of Japan in 1980 and followed-up until 1999. Population size of the municipality in which the aforementioned areas were located was used to distinguish between urban and rural areas, because municipalities in Japan are classified as village, town or city principally by population size. We applied a multilevel logistic regression model to take into account the hierarchical data structure of individuals (subjects) (level 1) nested within areas (level 2), and then calculated odds ratios and 95% confidence intervals (CIs) of deaths from total stroke. Statistically significant variance between areas was not observed in men but was in women. Age-adjusted odds ratios of the areas in the medium (population > or = 30,000 and <300,000) and small municipalities (<30,000) compared with the areas in the large municipalities (> or = 300,000) were 1.31 and 1.40 in men, and 1.32 and 1.62 in women, respectively. Multivariate-adjusted odds ratios (adjusted for age, body mass index, total cholesterol, diabetes, hypertension, current smoking, and daily alcohol consumption) of the areas in the medium and small municipalities compared with the areas in the large municipalities were 1.29 and 1.36 in men, and 1.34 and 1.68 in women, respectively. In conclusion, stroke mortality tended to be higher in rural areas than in urban areas in Japan, especially among women.

Reduced cerebral ischemia-reperfusion injury in Toll-like receptor 4 deficient mice

Inflammatory reaction plays an important role in cerebral ischemia-reperfusion injury, however, its mechanism is still unclear. Our study aims to explore the function of Toll-like receptor 4 (TLR4) in the process of cerebral ischemia-reperfusion. We made middle cerebral artery ischemia-reperfusion model in mice with line embolism method. Compared with C3H/OuJ mice, scores of cerebral water content, cerebral infarct size and neurologic impairment in C3H/Hej mice were obviously lower after 6 h ischemia and 24 h reperfusion. Light microscopic and electron microscopic results showed that cerebral ischemia-reperfusion injury in C3H/Hej mice was less serious than that in C3H/OuJ mice. TNF-alpha and IL-6 contents in C3H/HeJ mice were obviously lower than that in C3H/OuJ mice with ELISA. The results showed that TLR4 participates in the process of cerebral ischemia-reperfusion injury probably through decrease of inflammatory cytokines. TLR4 may become a new target for prevention of cerebral ischemia-reperfusion injury. Our study suggests that TLR4 is one of the mechanisms of cerebral ischemia-reperfusion injury besides its important role in innate immunity.

Differences in circadian variation of cerebral infarction, intracerebral haemorrhage and subarachnoid haemorrhage by situation at onset

BACKGROUND

The precise time of stroke onset during sleep is difficult to specify, but this has a considerable influence on circadian variations of stroke onset.

AIM

To investigate circadian variations in situations at stroke onset--that is, in the waking state or during sleep--and their differences among subtypes.

METHODS

12,957 cases of first-ever stroke onset diagnosed from the Iwate Stroke Registry between 1991 and 1996 by computed tomography or magnetic resonance imaging were analysed. Circadian variations were compared using onset number in 2-h periods with relative risk for the expected number of the average of 12 2-h intervals in the waking state or during sleep in cerebral infarction (CIF), intracerebral haemorrhage (ICH) and subarachnoid haemorrhage (SAH).

RESULTS

ICH and SAH showed bimodal circadian variations and CIF had a single peak in all situations at onset, whereas all three subtypes showed bimodal circadian variations of stroke onset in the waking state only. These variations were different in that CIF showed a bimodal pattern with a higher peak in the morning and a lower peak in the afternoon, whereas ICH and SAH had the same bimodal pattern with lower and higher peaks in the morning and afternoon, respectively.

CONCLUSIONS

Sleep or status in sleep tends to promote ischaemic stroke and suppress haemorrhagic stroke. Some triggers or factors that promote ischaemic stroke and prevent haemorrhagic stroke in the morning cause different variations in the waking state between ischaemic and haemorrhagic stroke.

Medical costs of patients with hypertension and/or diabetes: A 10-year follow-up study of National Health Insurance in Shiga, Japan

BACKGROUND AND METHODS

A cohort study investigating medical costs associated with the combination of hypertension and diabetes was conducted. The participants included 4535 community-dwelling Japanese individuals, aged 40-69 years, who were classified into the following four categories: 'Neither hypertension nor diabetes', 'Hypertension alone', 'Diabetes alone' or 'Both hypertension and diabetes'. Medical costs per person per month were compared among the four categories.

RESULTS AND CONCLUSION

Of the study population, 1.3% had both hypertension and diabetes. During the 10-year follow-up period, participants with both hypertension and diabetes incurred higher medical costs, as compared with those without hypertension, diabetes or their combination, even after adjustment for other confounding factors.

Risk assessment chart for death from cardiovascular disease based on a 19-year follow-up study of a Japanese representative population

BACKGROUND

Based on the NIPPON DATA80, risk charts for the probability of death from coronary heart disease (CHD), stroke, and all cardiovascular disease (CVD) were constructed by sex and 10-year age groups.

METHODS AND RESULTS

The 9,638 participants were followed-up for 19 years from 1980, excluding 28 individuals without the necessary baseline data and 257 participants with past history of stroke or CHD. Final analysis was performed on 9,353 participants (4,098 men, mean age 50.3 years; 5,255 women, mean age 50.8) using a Cox proportional hazards model. Death probabilities over a 10-year period from CHD, stroke, and all CVD were calculated and displayed as color coding on each chart by combining 10-year age, systolic blood pressure, smoking, and serum total cholesterol and glucose levels. Six different colors corresponding to probabilities of death were displayed on each chart.

CONCLUSIONS

The original charts based on the findings from NIPPON DATA80 are suitable for assessing CHD, stroke, and all CVD death risk in the general Japanese population. These charts should be used as a health-education tool for lifestyle modification targeting individuals with CVD risk factors.

The relationships of proteinuria, serum creatinine, glomerular filtration rate with cardiovascular disease mortality in Japanese general population

Proteinuria, high serum creatinine, and reduced glomerular filtration rate (GFR) have been associated with increased mortality from cardiovascular disease (CVD) and all causes. However, the combined effect of proteinuria with serum creatinine and GFR on CVD or all-cause mortality has not been well investigated. We conducted a 10-year prospective cohort study of 30,764 men and 60,668 women aged 40-79 years who participated in annual health checkups in 1993. The Cox proportional hazards model was used to estimate the relative risk (RR) after adjusting for age, smoking, and other cardiovascular risk factors. The multivariable RR (95% confidence interval (CI)) of CVD death for positive vs negative proteinuria was 1.38 (1.05-1.79) among men and 2.15 (1.64-2.81) among women. The respective RR for the highest vs lowest creatinine groups (> or = 1.3 vs < or = 0.8 mg/dl for men and > or = 1.1 vs < or = 0.6 mg/dl for women) was 1.56 (1.19-2.04) among men and 2.15 (1.58-2.93) among women. The respective RR for GFR < 60 vs > r = 100 ml/min/1.73 m2 was 1.65 (1.25-2.18) among men and 1.81 (1.39-2.36) among women. For individuals with proteinuria combined by hypercreatininemia or reduced GFR, the risk of CVD death was two-fold higher in men and 4-6-fold higher in women compared to those without proteinuria and with normal creatinine level or GFR. Similar associations were observed for stroke, coronary heart disease, and all-cause mortality. Proteinuria, and hypercreatininemia or reduced GFR and their combination were significant predictors of CVD and all-cause mortality.

The value of combining serum alanine aminotransferase levels and body mass index to predict mortality and medical costs: a 10-year follow-up study of National Health Insurance in Shiga, Japan

BACKGROUND

Evidence suggests that the predictive value of serum alanine aminotransferase (ALT) levels for prognosis, measured by indices such as all-cause mortality and medical costs, may be modified by body mass index (BMI). However, the relationship between serum ALT and BMI has not been satisfactorily elucidated.

METHODS

Four thousand, five hundred and twenty-four community dwelling Japanese National Health Insurance beneficiaries, 40-69 years old, were classified into five categories according to their serum ALT levels (IU/L) (ALT<20, 20< or =ALT<30, 30< or =ALT<40, 40< or =ALT<50 and 50< or =ALT) and followed for 10 years. Hazard ratios for all-cause mortality, with reference to the lowest serum ALT category, and medical costs per person were evaluated for each serum ALT category after analyzing interactions between serum ALT levels and BMI for all-cause mortality and for medical costs.

RESULTS

A significant interaction between serum ALT levels and BMI was observed. In participants below the median BMI, positive, graded relationships were identified between serum ALT levels and all-cause mortality as well as between serum ALT levels and personal medical costs. The multivariate-adjusted hazard ratio in the "50< or =ALT" category showed an approximately 8-fold increase. However, in the participants at or above the median BMI, no significant relationships between serum ALT levels and all-cause mortality or personal medical costs were identified.

CONCLUSIONS

In these Japanese participants, the predictive value of serum ALT levels for prognosis was more evident if BMI was taken into account. A combination of high serum ALT levels and below median BMI was associated with excess mortality and medical costs.

Electrocardiogram Screening for Left High R-Wave Predicts Cardiovascular Death in a Japanese Community-Based Population: NIPPON DATA90

Little is known about the efficacy of left ventricular hypertrophy diagnosed by electrocardiography for predicting cardiovascular disease in a general Japanese population. In a large cohort of participants selected randomly from the overall Japanese population, we attempted to evaluate the usefulness of a high amplitude R-wave (left high R-wave) on the electrocardiogram for predicting cardiovascular death. A total of 6,688 Japanese (mean age, 50.7 years old; 57% women) free of previous cardiovascular disease and use of antihypertensive agents at baseline were followed for 10 years, from 1990 to 2000. Left high R-wave on the electrocardiogram (the Minnesota Code, 3-1 or 3-3) was found in 9.4% of the 6,688 participants, in 14.6% of the 2,413 hypertensives and in 6.4% [corrected] of the 4,275 normotensives. During the follow-up period, 133 [corrected] participants died due to cardiovascular disease. After adjustment for systolic blood pressure and other risk factors, left high R-wave conferred an increased risk of cardiovascular death; the hazard ratio among all the participants was 1.88 (95% confidence interval, 1.22-2.89; p < 0.01), that among hypertensives was 1.97 (1.20-3.24; p = 0.01), and that among normotensives was 1.66 (0.69-3.98; p = 0.26). The population attributable risk percent of left high R-wave for cardiovascular death was 7.6% among all participants, 12.4% among hypertensives and 4.1% among normotensives. Left high R-wave on electrocardiogram, irrespective of the level of systolic blood pressure, was a predictive marker for cardiovascular death among community-dwelling Japanese.

Incidence of acute myocardial infarction in Takashima, Shiga, Japan

BACKGROUND

The incidence and mortality from ischemic heart disease (IHD) in Japan seem to be among the lowest of all the industrialized countries, but there are few reliable registers of acute myocardial infarction (AMI).

METHODS AND RESULTS

To assess the incidence of AMI in Takashima County, Shiga, Japan, from 1988 to 1998 and compare the data with similar registers in the world, cases of AMI or sudden death presumed from myocardial ischemia were registered. The criteria of AMI were based on the WHO MONICA Projects. The medical records of all the hospitals inside as well as outside the county, the original death records in the health center, and the ambulance records in the county were investigated and 291 cases were registered (190 males, 101 females; average age (mean +/- SD), 69.5+/-12.2). The 28-day and 24-h case fatality was 38.1% and 33.0%, respectively. Age-adjusted annual incidence of AMI per 100,000 population aged between 25 and 74 years were 58.2 for men and 18.0 for women. The incidence of AMI showed a constant trend from 1988 to 1998.

CONCLUSION

The results confirmed that Japan has the lowest incidence of AMI among the industrialized countries.