Why are the Japanese living longer?

Relationship of socioeconomic status to C-reactive protein and arterial stiffness in urban Japanese civil servants

This study investigates whether the two socioeconomic status indicators, educational level and employment grade, are associated with C-reactive protein (CRP) levels and arterial stiffness among Japanese urban civil servants. Brachial-ankle pulse-wave velocity (baPWV) as an indicator of arterial stiffness, CRP, occupational stress and conventional risk factors were evaluated in 3412 men and 854 women. Although the socioeconomic gradient showed a significant association with the CRP levels in men after adjustment for age, the significance disappeared after multivariate adjustment, whereas in women, the socioeconomic gradient showed no significant association with the CRP levels. In men, educational level was significantly associated with the baPWV value after adjustment for conventional risk factors, CRP and occupational stress (P for trend <0.0001). With regards to employment grade, only low-level non-manual workers had a significantly lower baPWV value as compared to manual workers at a fully adjusted model, and trend significance disappeared. However, in women, neither educational level nor employment grade was associated with the baPWV value. In summary, the socioeconomic gradient, especially the educational level, was significantly inversely related to the baPWV value in men. In women, the socioeconomic gradient was not related to the baPWV value. An inverse relationship between the socioeconomic gradient and CRP levels was found in men only after age adjustment. We suggest that because the educational level is an important aspect in the adolescent environment and hence might influence the future lifestyle, early health education should be provided to prevent an unfavourable lifestyle and atherosclerotic diseases in later life.

Interplay of politics and law to promote health: improving economic equality and health: the case of postwar Japan

The health situation in Japan after World War II was extremely poor. However, in less than 35 years the country's life expectancy was the highest in the world. Japan's continuing health gains are linked to policies established at the end of World War II by the Allied occupation force that established a democratic government. The Confucian principles that existed in Japan long before the occupation but were preempted during the war years were reestablished after the war, facilitating subsequent health improvements. Japan's good health status today is not primarily the result of individual health behaviors or the country's health care system; rather, it is the result of the continuing economic equality that is the legacy of dismantling the prewar hierarchy.

Different income information as an indicator for health inequality among Japanese adults

BACKGROUND

There are several alternative indicators of income information, which is a fundamental measure of individual socioeconomic position. In this study, we compared the degrees of associations of four types of income information with health variables among Japanese adults.

METHODS

Using a nationally representative sample of 29,446 men and 32,917 women aged 20 years and over, the associations between four income indicators and health variables were examined using the odds ratio in logistic regression analysis and the concentration index by sex and age group (20-59 years and 60+ years). Income indicators consisted of total household income, equivalent household income, total household expenditure, and equivalent household expenditure. Current smoking and self-rated health statuses were used as health variables.

RESULTS

A low income was associated with a high prevalence of smoking and fair/poor self-rated health, with some differences among sex and age groups and income indicators, but less difference among methods of statistical analyses. Total and equivalent incomes were similarly and more markedly associated with smoking and self-rated health statuses, whereas equivalent expenditure showed the smallest degree of health difference. For the population aged 60+ years, the degree of health differences in smoking was similar between income and expenditure.

CONCLUSIONS

Although the degree of income-related health differences is dependent on health outcome and both sex and age group, this study suggests that either crude or equivalent household income is a useful indicator for health inequality among Japanese adults.

Calcium intake pattern among Japanese women across five stages of health behavior change

BACKGROUND

The transtheoretical model (TTM) of health behavior change is one of the most promising approaches for health professionals to help individuals change their behaviors. Few studies have assessed calcium intake using the model on Asian women. This study aims at clarifying characteristics of each behavioral stage among Japanese women and providing clues to increase calcium intake to prevent osteoporosis.

METHODS

A cross-sectional survey was conducted from September through November, 2005 using self-administered questionnaires. A total of 226 participants in an osteoporosis screening program were invited to take part in the study, and 150 women were enrolled.

RESULTS

Adjusted means of total dietary calcium were positively significantly associated with successive stages (p<0.001). The proportion of calcium intake from plants and fish was higher in the precontemplation, contemplation, and preparation stages compared with the action and maintenance stages (p=0.038). Concomitantly, the plants and fish food group contributed 46.7% of total dietary calcium, while 32.4% was derived from milk and dairy food, and 20.9% from other foods. The correlation coefficient (95% confidence interval) between the proportion of calcium obtained from plants and fish and the proportion of fat energy was -0.22 (-0.37, -0.06).

CONCLUSIONS

The proportion of calcium intake from plants and fish was higher among women in the lower stages compared with higher stages. Given the higher prevalence of lactose intolerance, it would seem plausible to recommend lower-stage women be educated and encouraged to derive more calcium from plants and fish diets as a means to prevent osteoporosis.

Higher mortality in areas of lower socioeconomic position measured by a single index of deprivation in Japan

OBJECTIVES

To formulate an index representing area deprivation and elucidate the relation between the index and mortality in Japan.

STUDY DESIGN

Ecological study for prefectures (N=47) and municipalities (N=3366) across Japan.

METHODS

Based on socioeconomic indicators of seven domains of deprivation (i.e. unemployment, overcrowding, low social class and poverty, low education, no home ownership, low income and vulnerable group), an index was formulated using the z-scoring method. The relation between the index and mortality was examined by correlation analysis, hierarchical Poisson regression and comparison of standardized mortality ratio according to the index.

RESULTS

The deprivation index ranged from -7.48 to 10.98 for prefectures and from -16.97 to 13.82 for municipalities. The index was significantly positively correlated with prefectural mortality, especially in the population aged under 74 years: r=0.65 for men and r=0.41 for women. At the municipal level, hierarchical Poisson regression showed a significant positive coefficient of the index to mortality for both men and women, and excess mortality in the most deprived fifth compared to the least deprived fifth was 26.4% in men and 11.8% in women.

CONCLUSIONS

We formulated a deprivation index, which was substantially related to mortality at the prefectural and municipal levels. This study highlights the higher risk of dying among populations in socially disadvantaged areas and encourages the use of indices representing area socioeconomic conditions for further studies of area effects on health.

Social class inequalities in self-rated health and their gender and age group differences in Japan

BACKGROUND

Few studies have examined social inequalities in self-rated health in Japan, and the issue of gender differences related to social inequalities in self-rated health remains inconclusive.

METHODS

The data derived from interviews with 2987 randomly selected Japanese adults in four prefectures in Japan who completed the cross-national World Mental Health survey from 2002 through 2005. We calculated odds ratios (ORs) of having poor self-rated physical and mental health by two social class indicators independently with multivariate logistic regression models, adjusted for age, gender, marital status, and area. Stratified analyses by gender and age group were also conducted.

RESULTS

The adjusted ORs of the lowest educational attainment category having poor self-rated physical and mental health were 1.42 (95% confidence interval [CI]: 1.15-1.76) and 1.37 (95% CI: 1.10-1.70), respectively. Among females, educational attainment had significant linear associations with self-rated physical and mental health. Adjusted household income was also significantly associated with self-rated physical health among female respondents. No associations were found among males. While educational attainment was associated with self-rated health among the young age group, adjusted household income was associated with self-rated physical health in the middle and old age group.

CONCLUSION

These results indicated social inequalities in self-rated health and prominent social inequalities in self-rated health among females in Japan. Social inequalities in self-rated health seemed to exist across age groups. However, the mechanism of social inequalities in self-rated health could be different depending on the age group.

Multiple roles and mental health in cross-cultural perspective: the elderly in the United States and Japan

This paper examines how multiple roles affect the mental health of the elderly in Japan and the United States, two countries with vastly different cultures. Hypotheses were drawn based on the cultural differences in role experiences, and these hypotheses are tested by analyzing nationally representative samples of the elderly in these countries. The results show that Americans are more likely to be involved in roles related to family, work, and community, while the Japanese are more likely to be involved in only those roles related to family and work. Multiple roles are also found to be less beneficialfor the mental health of Japanese elderly compared to American counterparts. National differences in the effects of individual roles and role configurations on mental health are also documented. Overall, the results show the importance of broad cultural contexts for understanding the relationship between roles and mental health.

Socioeconomic factors and cancer incidence, mortality, and survival in a metropolitan area of Japan: a cross-sectional ecological study

Cancer mortality is generally high in people of low socioeconomic status compared with people of high socioeconomic status (SES). Although these differences in mortality may be caused by differences in cancer incidence and survival, analysis of these factors has rarely been conducted. The objective of our cross-sectional ecological study was to analyze socioeconomic differences in cancer incidence, mortality and survival in a metropolitan area of Japan. The age-adjusted cancer incidence rates, age-adjusted mortality rates, relative 5-year survival, and proportions of early stage cancer were calculated for 67 municipalities in Osaka, Japan. For area-based socioeconomic variables, we used the percentages of male unemployment, college or graduate school graduates, home ownership, households receiving government assistance, and households below the subsistence habitation level in each municipality. We performed linear regression taking each municipality's population as weight to examine the relationships between measurements relating cancer and socioeconomic variables. Factor analysis of socioeconomic variables was carried out to determine whether a particular socioeconomic variable tended to be associated with another. Cancer incidence, cancer mortality, 5-year cancer survival, and proportion of early stage cancer were highly correlated with each socioeconomic variable at the municipality level. Five area-based socioeconomic variables could be explained by three factors: economic status, housing characteristics and educational attainment. Despite the major limitation of a lack of individual information about socioeconomic characteristics and outcomes related to cancer, we hypothesize that a municipal area's socioeconomic status might be a predictor of individual incidence, mortality, and survival of cancer.

Accumulation of health risk behaviours is associated with lower socioeconomic status and women's urban residence: a multilevel analysis in Japan

Background

Little is known about the socioeconomic differences in health-related behaviours in Japan. The present study was performed to elucidate the effects of individual and regional socioeconomic factors on selected health risk behaviours among Japanese adults, with a particular focus on regional variations.

Methods

In a nationally representative sample aged 25 to 59 years old (20,030 men and 21,076 women), the relationships between six risk behaviours (i.e., current smoking, excessive alcohol consumption, poor dietary habits, physical inactivity, stress and non-attendance of health check-ups), individual characteristics (i.e., age, marital status, occupation and household income) and regional (N = 60) indicators (per capita income and unemployment rate) were examined by multilevel analysis.

Results

Divorce, employment in women, lower occupational class and lower household income were generally associated with a higher likelihood of risk behaviour. The degrees of regional variation in risk behaviour and the influence of regional indicators were greater in women than in men: higher per capita income was significantly associated with current smoking, excessive alcohol consumption, stress and non-attendance of health check-ups in women.

Conclusion

Individual lower socioeconomic status was a substantial predictor of risk behaviour in both sexes, while a marked regional influence was observed only in women. The accumulation of risk behaviours in individuals with lower socioeconomic status and in women in areas with higher income, reflecting an urban context, may contribute to their higher mortality rates.

Municipal socioeconomic status and mortality in Japan: sex and age differences, and trends in 1973-1998

The purpose of this study was to examine the sex and age differences and the time trends in the association between municipal socioeconomic status (SES) and all-cause mortality across Japan from 1973 to 1998. Sex-specific mortality of municipalities (N=3319 in 1995) by age groups (total, under 75-year, and over 75-year populations) was linked to municipal SES indicators related to income, education, unemployment and living space, and two SES composite indices formulated by principle component analysis (Index 1 related to lower income and education, and Index 2 related to unemployment and overcrowding). The relation was assessed using mortality gradients by SES quintiles and Bayesian hierarchical Poisson regression. The results showed that a lower SES was related to higher mortality for all SES indicators and composite indices. The mortality gradient was steeper for the under 75-year population than the total and over 75-year populations, and the relation between mortality and income- and education-related indicators/index was stronger for males than for females. The time trend showed an increase in the relation for Index 2, while a decrease for Index 1. This study demonstrated that lower municipal SES had an adverse influence on population health, and the influence was marked for males and premature death. Although a substantial health disadvantage still remained in lower SES areas, the impact of SES factors on geographical health variation changed over time; the association with mortality has weakened for income and education, while it has strengthened for unemployment and living space.

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

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

Analysis of health-related quality of life (HRQL), its distribution, and its distribution by income in Japan, 1989 and 1998

Research conducted over the past decade has increasingly focused on health inequality. The goals of improving the health of a population are now often expressed as the increase in the average level of health and the decrease in health inequality as clearly specified in the Healthy People 2010 and the World Health Report 2000. Using a nationally representative sample of the 1989 and 1998 waves of the Japanese Comprehensive Survey of Living Conditions of the People on Health and Welfare (CSLC), this research examines the average health-related quality of life (HRQL), its distribution, and its distribution by income share. This study departs from previous health inequality analyses in the following two ways: (1) construction of a measure of HRQL in the CSLC and its application to health inequality analysis, and (2) inclusion of the dead in health inequality analysis using a cross-sectional survey. This study found that between 1989 and 1998 the average HRQL in Japan slightly reduced (0.005 reduction), its inequality by income slightly reduced (0.002 reduction in the difference between the top 20% and bottom 20% income share groups), and its inequality measured by the Gini coefficient slightly increased (0.002 increase). Women's HRQL was almost always lower than men's, except in earlier ages younger than 10 years old. HRQL was more unequally distributed among women than men and in older ages. This analysis shows that the success in the improvement in the length of life in Japan did not always coincide with the improvement in HRQL and provides a basis for the future population health research.

Increased excess deaths in urban areas: quantification of geographical variation in mortality in Japan, 1973-1998

To quantify the magnitude of geographical health inequality by sex and age group, and to observe the change in regional distribution of health disadvantage, this study estimated excess deaths attributable to the mortality variation among municipalities across Japan from 1973 through 1998. The municipalities (N = 3340 in 1995) were divided into quintiles according to standardized mortality ratio (SMR). Using the mortality of the lowest SMR quintile as the standard, the number of excess deaths (ED) and its ratio to observed deaths (EDR) were estimated by sex, age group (total population and under 65-year population) and regional block in 1973-1977, 1978-1982, 1983-1987, 1988-1992 and 1993-1998. Total annual ED in 1993-1998 was estimated as 47,124 for males and 46,562 for females, representing EDR of 9.9 and 11.6%, respectively. The under 65-year population had a higher EDR than the total population. Rural regions showed a marked decrease in EDR in contrast to the increase in urban regions over time. The present study suggests that the reduction of a large number of deaths, especially premature deaths, is expected by elimination of geographical health inequality, and that health policies for urban residents are prioritized.

Influence of death from circulatory diseases on life expectancy at birth in Japan

This study aims to evaluate the contribution of the change in circulatory diseases mortality to the life expectancy at birth observed during the years 1955-1995 in Japan. We used data on the population and the number of deaths by cause, age, and sex in 1955, 1965, 1975, 1985, and 1995. The contribution of different ages and causes of death to the change in life expectancy were examined with the method developed by Pollard. We found that the reduction in circulatory diseases mortality contributed to the improvements in life expectancy for both sexes during the decade 1975-1985. Much of this was due to the decrease in cerebrovascular disease. In the years 1985-1995, however, the contribution of cerebrovascular disease decreased in both sexes, while that of heart disease grew to become the largest of any single condition. By age, the contribution of all circulatory diseases increased among the elderly in recent years. The contribution of the change in circulatory diseases mortality to the life expectancy at birth has increased in recent years but seems to have reached a plateau. The weight against improvements in life expectancy in middle-aged people has shown little change, so that reducing the mortality rate in middle-aged people is now a major issue.

Old age mortality in Japan: does the socioeconomic gradient interact with gender and age?

OBJECTIVES

There is limited knowledge concerning how the effects of socioeconomic status (SES) on mortality interact with gender and age. In addition, current studies are largely based on data from the Western nations. The validity of prior observations needs to be further evaluated. This research examines socioeconomic inequalities in old age mortality in Japan, with a special emphasis on how inequalities interact with gender and age.

METHODS

Data came from a 5-wave panel study of a national probability sample of 2,200 elderly Japanese conducted between 1987 and 1999. Hazard rate models involving time-varying covariates were used to ascertain the direct and indirect effects of SES. In addition, interaction effects involving SES variables with age and gender were evaluated.

RESULTS

In contrast to prior findings from the Western developed nations, there is an educational crossover effect on mortality among older men, in that, at advanced age, those with less education live longer than those with higher education. On the other hand, there is some evidence that educational differences in the risk of dying tend to converge in the 70-79 age group. More interestingly, there is a crossover in the effect of education among the 80 and older age group.

DISCUSSION

The observation that educational crossover exists only among elderly men may be because of gender and SES differences in causes of death, morbidity, and health behavior. On the other hand, possible explanations for age differences in the educational crossover include selective survival and cohort effects.

Oral health status and its inequality among education groups: comparing seven international study sites

This study compares oral health status and its inequality among education groups across seven study sites in five countries: Erfurt, Germany; Lodz, Poland; Yamanashi, Japan; New Zealand; and Baltimore and the Lakota and Navajo Indian Health Service sites in the United States. The data, from the International Collaborative Study of Oral Health Outcomes, were collected through personal interviews and clinical examinations. The research group measured the study sites' overall oral health, examining the percentage of the population with five or more missing and two or more decayed teeth. The group also assessed the magnitude of inequality among education groups by using indices of excess morbidity. Baltimore had the lowest percentage (10.8 percent) of decayed teeth and second lowest percentage (17.3 percent) of missing teeth, but the greatest indices of excess morbidity (79.2 percent for missing, 73.1 percent for decayed). Lodz, by contrast, had the worst overall dentition status (75.3 percent for missing, 70.3 percent for decayed) but the lowest inequality indices (10.6 percent for missing, 13.8 percent for decayed). This study demonstrates the need for policymakers in the study countries to consider not only overall levels but also the distribution of oral health, and it presents various challenges for oral health professionals in designing and implementing oral health programs.

Hypocholesterolemia is a significant predictor of death in a cohort of chronic hemodialysis patients

BACKGROUND

Although hypocholesterolemia is common in chronic hemodialysis patients, its effect on survival has not been studied in a large patients population.

METHODS

A cohort of chronic hemodialysis patients (N = 1167) was prospectively followed from January 1991 to January 2001. The survival impact of this cohort, who were divided according to different baseline levels of serum cholesterol, were calculated with the multivariate Cox proportional hazard analysis after adjusting for baseline clinical and laboratory variables.

RESULTS

During the study period, 567 (48.6%) patients died. The mean (SD) baseline level of serum cholesterol was 171.0 (40.8) mg/dL and ranged from 76 to 378 mg/dL. The five-year survival rate was highest (0.812) in the subgroup that had a serum cholesterol range of 200 to 219 mg/dL and was lowest (0.608) in the subgroup with serum cholesterol values of <140 mg/dL. The five-year survival rate was 0.735 in the subgroup with serum cholesterol of > or =220 mg/dL. Serum cholesterol was a significant predictor of death with an adjusted hazards ratio (95% confidence interval) was 0.939 (0.891 to 0.989). In a subgroup of patients with serum albumin values > or =4.5 g/dL (N = 128), the adjusted hazards ratio was even greater at 1.370 (1.105 to 1.692). Other than sex, body mass index and serum albumin were significant determinants of baseline levels of serum cholesterol.

CONCLUSIONS

Hypocholesterolemia was an independent predictor of death in patients on chronic hemodialysis. This impact of hypercholesterolemia on survival was only evident in a subgroup of patients whose serum albumin was more than 4.5 g/dL.

Demographic trends in the Okinawa Dialysis Study (OKIDS) registry (1971-2000)

BACKGROUND

The clinical demographics of chronic dialysis patients are changing worldwide. However, long-term data from regional dialysis registries have not yet been analyzed and reported.

METHODS

The Okinawa Dialysis Study (OKIDS) registry included all chronic dialysis patients treated in Okinawa, Japan, since 1971. Data for the years 1971 to 1990 were analyzed to predict trends for 1991 to 2000. The predicted values were then compared to the actual values and analyzed statistically, with particular attention being paid to relative risk of death. Multivariate Cox proportional hazards analysis was done to analyze the time factors of relative risk of death.

RESULTS

A total of 5246 patients (2981 men and 2265 women) were registered and the total duration of observation was 28,431 patient-years. The prevalence and incidence of dialysis patients expressed per million population were 2320 and 297, respectively, in 2000, values that were significantly higher (P < 0.02 for both) than the predicted values. The gross mortality rate per 1000 patient-years was 118.4 for 1971 to 1980, 63.3 for 1981 to 1990, and 77.7 for 1991 to 2000. The adjusted hazards ratio (95% confidence interval) for mortality was 0.743 (0.650 to 0.862) for 1981-1990 and 0.721 (0.659 to 0.790) for 1991 to 2000 in comparison to the risk of mortality in 1971 to 1980. The decrease in mortality rate was largely due to the drop in cardiac deaths from 71.0 for 1971 to 1980 to 17.2 for 1991 to 2000.

CONCLUSIONS

The incidence and prevalence of chronic dialysis patients increased more than expected over the past decade in Okinawa, Japan. Despite the rapid change in patient demographics, the survival rate did not decrease significantly.

Individual income, income distribution, and self rated health in Japan: cross sectional analysis of nationally representative sample

OBJECTIVE

To assess the effects on self rated health of individual income and income distribution in Japan.

DESIGN

Cross sectional analysis. Data collected on household income, self rated health, and other sociodemographic characteristics at the individual level from comprehensive survey of the living conditions of people on health and welfare in a nationally representative sample from each prefecture.

SETTING

Prefectures in Japan.

PARTICIPANTS

80 899 people aged >15 years with full records in survey.

MAIN OUTCOME MEASURES

Dichotomous variable for self rated health of each respondent (0 if excellent, very good or good; 1 if fair or poor).

RESULTS

Inequality in income at the prefecture level measured by the Gini coefficient was comparable with that in other industrialised countries. Unadjusted odds ratios show a 14% increased risk (odds ratio 1.14, 95% confidence interval 1.02 to 1.27) in reporting poor or fair health for individuals living in prefectures with higher inequality in income. After adjustment, individual income was more strongly associated with self rated health than income inequality. Additional inclusion of regional effects showed that median income at the prefecture level was inversely related to self rated health.

CONCLUSIONS

Individual income, probably relative to the median prefecture income, has a stronger association with self rated health than income inequality at the prefecture level.

Evidence for high incidence of end-stage renal disease in patients after stroke and acute myocardial infarction at age 60 or younger

The impact of stroke and acute myocardial infarction (AMI) on the incidence of end-stage renal disease (ESRD) is unknown. Two community-based registries, one of patients with stroke or AMI and another of patients with ESRD who undergo dialysis, are available in Okinawa, Japan. Whether survivors after stroke and AMI who were registered from April 1988 through March 1991 entered an ESRD dialysis program by the end of December 1999 was determined. Among 4,556 patients (3,809 patients with stroke, 747 patients with AMI) who survived at least 28 days after the event onset, 44 patients (36 patients, stroke; 8 patients, AMI) entered an ESRD dialysis program during the study period. The 10-year cumulative incidence of ESRD was approximately 2.0% in those who survived stroke or AMI. The observed-expected ratio was 4.1 in men (P < 0.01) and 5.8 in women (P < 0.01) aged 30 to 59 years and 0.8 in men (not significant) and 0.4 in women (not significant) 60 years and older. The present results confirm that survivors after stroke or AMI have a greater incidence of ESRD than those in the general population, in particular, those who had stroke or AMI at 60 years or younger.

Transitions in functional status among older people in Wuhan, China: socioeconomic differentials

The vast majority of research on socioeconomic status (SES) and old-age disability is based on data derived from the developed nations. This study evaluates the external validity of current findings by examining old-age disability in China, a developing nation. The direct, indirect, and total effects of SES on disability transitions were ascertained during a 3-year period in a probability sample of 2,943 people aged 60 years or older in Wuhan, China. As SES measures, education and urban residence exert distinct direct and indirect effects on functional transitions with complicated underlying mechanisms. SES has differential effects on functional transitions depending on one's prior functional state. Furthermore, the generally positive effects of SES are partially offset by negative indirect effects

Socioeconomic differences in behavioural and biological risk factors: a comparison of a Japanese and an English cohort of employed men

BACKGROUND

To compare socioeconomic differences in behavioural and biological risk factors in Japanese and English 39-59-year-old employed men.

METHODS

We measured systolic and diastolic blood pressure, total and high density lipoprotein (HDL) cholesterol, body mass index (BMI), waist-to-hip ratio and fibrinogen at medical screenings and smoking and alcohol consumption in health questionnaires among Japanese non-manual and manual employees of a steel products company and among English non-manual employees working in Civil Service departments.

RESULTS

In England, higher employment grades were advantaged with regard to most risk factors studied. In Japan the picture was different in that higher grades had higher BMI, waist-to-hip-ratio and lower HDL cholesterol. In Japan employment grade differences in these three risk factors are clearly larger among younger men than among older men, while in England age differentials in the grade differences are small. Similar results were obtained for education.

CONCLUSIONS

Important differences in the social patterning of risk factors were observed in our cohorts of employed Japanese and English men. The contribution that these risk factors make in explaining social differences in health may vary accordingly. Studies that identify the common and unique determinants of socioeconomic health differences in different populations are needed.

Economic growth, income equality, and population health among the Asian Tigers

The "Tiger" economies of Southeast Asia provide examples of developing nations where economic growth and increasing income equality are compatible and, when occurring together, are associated with superior health trends over time. The degree of income inequality in the Asian Tigers declined during the period of rapid economic growth. Traditionally, economists have viewed economic growth and relative parity in income distribution as incompatible, or trade-offs. This poses a public policy dilemma, since a reasonable propensity to increase a nation's overall economic well-being would mean forsaking measures that increase income parity. The Asian Tigers, however, have shown that this need not be viewed as a trade-off. Economic growth and a simultaneous increase in income equality are possible and, with respect to health outcomes, desirable. The authors propose a variety of mechanisms through which income inequality can enhance economic growth, and discuss policies in education, agricultural land reform, and housing that influence the simultaneous attainment of income equality and economic growth.

Silent and clinically overt stroke in older Japanese subjects with white-coat and sustained hypertension

OBJECTIVES

We investigated whether white-coat hypertension is a risk factor for stroke in relation to silent cerebral infarct (SCI) in an older Japanese population.

BACKGROUND

It remains uncertain whether white-coat hypertension in older subjects is a benign condition or is associated with an increased risk of stroke.

METHODS

We studied the prognosis for stroke in 958 older Japanese subjects (147 normotensives [NT], 236 white-coat hypertensives [WCHT] and 575 sustained hypertensives [SHT]) in whom ambulatory blood pressure monitoring was performed in the absence of antihypertensive treatment. In 585 subjects (61%), we also assessed SCI using brain magnetic resonance imaging.

RESULTS

Silent cerebral infarcts were found in 36% of NT (n = 70), 42% of WCHT (n = 154), and 53% of SHT (n = 361); multiple SCIs (the presence of > or =2 SCIs) were found in 24% of NT, 25% of WCHT and 39% of SHT. During a mean 42-month follow-up period, clinically overt strokes occurred in 62 subjects (NT: three [2.0%]; WCHT: five [2.1%]; SHT: 54 [9.4%]), with 14 fatal cases (NT: one [0.7%]; WCHT: 0 [0%]; SHT: 13 [2.3%]). A Cox regression analysis showed that age (p = 0.0001) and SHT (relative risk, [RR] [95% confidence interval, CI]: 4.3 [1.3-14.2], p = 0.018) were independent stroke predictors, whereas WCHT was not significant. When we added presence/absence of SCI at baseline into this model, the RR (95% CI) for SCI was 4.6 (2.0-10.5) (p = 0.003) and that of SHT was 5.5 (1.8-18.9) versus WCHT (p = 0.004) and 3.8 (0.88-16.7) versus NT (p = 0.07).

CONCLUSIONS

In older subjects the incidence of stroke in WCHT is similar to that of NT and one-fourth the risk in SHT. Although SCI is a strong predictor of stroke, the difference in stroke prognosis between SHT and WCHT was independent of SCI. It is clinically important to distinguish WCHT from SHT even after assessment of target organ damage in the elderly.

Menopause, local biologies, and cultures of aging

Menopause marks the end of menstruation, once generally accepted as the closure of women's reproductive lives. The current medical view of menopause, however, is as a pathological event with its own distinct set of symptoms and diseases. Researchers have described women as facing a dramatic increase in the risk of heart disease, osteoporosis, stroke, and Alzheimer's, all as the result of the impact of changing hormone levels, particularly the decline in estrogen. The clinical literature has interpreted these findings in terms of the absolute necessity of replacing these lost hormones for all women who are menopausal regardless of any other physiological, social, or cultural characteristic they might possess. Using research done in Japan, Canada, and the United States, this paper challenges the notion of a universal menopause by showing that both the symptoms reported at menopause and the post-menopause disease profiles vary from one study population to the next. For most of the symptoms commonly associated with menopause in the medical literature, rates are much lower for Japanese women than for women in the United States and Canada, although they are comparable to rates reported from studies in Thailand and China. Mortality and morbidity data from these same societies are used to show that post-menopausal women are also not equally at risk for heart disease, breast cancer, or osteoporosis. Rather than universality, the paper suggests that it is important to think in terms of "local biologies", which reflect the very different social and physical conditions of women's lives from one society to another.

Japanese and Western diet and risk of idiopathic sudden deafness: a case-control study using pooled controls

BACKGROUND

One of the proposed aetiological mechanisms for idiopathic sudden deafness is vascular disease. However, it is not known whether traditional cardiovascular risk factors, such as particular dietary factors, are associated with this condition.

METHODS

A case-control study using pooled controls was conducted in Japan to investigate the relationship between idiopathic sudden deafness and diet. An m:n matched-pairs method was used to obtain age-, gender- and residential district-matched controls from a nationwide database of pooled controls. Food intake was assessed from a self-administered usual food frequency questionnaire that asked about intake of 35 foods (including four drinks). Participants were classified according to the frequency of intake of Western foods and the frequency of intake of traditional Japanese foods. Subgroup analyses were performed using audiometric subtypes of idiopathic sudden deafness.

RESULTS

Data were obtained for 164 cases and 20,313 controls. An increased risk of sudden deafness was observed among participants who frequently consumed Western foods (OR = 1.82, 95% CI : 1.14--2.89), and a decreased risk of this condition was observed among participants who frequently consumed Japanese foods (OR = 0.52, 95% CI : 0.33--0.82). A direct association of sudden deafness with Western food intake was evident for flat-type hearing loss.

CONCLUSIONS

This study suggests that a largely Western diet might be a risk factor for idiopathic sudden deafness, a traditional Japanese diet might be a preventive factor for this condition, or both. These findings are consistent with the hypothesis that vascular factors are an important cause of idiopathic sudden deafness, although the possibility of residual confounding by unmeasured confounders such as socioeconomic status cannot be ruled out.

Why reduce health inequalities?

It is well known that social, cultural and economic factors cause substantial inequalities in health. Should we strive to achieve a more even share of good health, beyond improving the average health status of the population? We examine four arguments for the reduction of health inequalities.1 Inequalities are unfair. Inequalities in health are undesirable to the extent that they are unfair, or unjust. Distinguishing between health inequalities and health inequities can be contentious. Our view is that inequalities become "unfair" when poor health is itself the consequence of an unjust distribution of the underlying social determinants of health (for example, unequal opportunities in education or employment).2 Inequalities affect everyone. Conditions that lead to marked health disparities are detrimental to all members of society. Some types of health inequalities have obvious spillover effects on the rest of society, for example, the spread of infectious diseases, the consequences of alcohol and drug misuse, or the occurrence of violence and crime.3 Inequalities are avoidable. Disparities in health are avoidable to the extent that they stem from identifiable policy options exercised by governments, such as tax policy, regulation of business and labour, welfare benefits and health care funding. It follows that health inequalities are, in principle, amenable to policy interventions. A government that cares about improving the health of the population ought therefore to incorporate considerations of the health impact of alternative options in its policy setting process.3 Interventions to reduce health inequalities are cost effective. Public health programmes that reduce health inequalities can also be cost effective. The case can be made to give priority to such programmes (for example, improving access to cervical cancer screening in low income women) on efficiency grounds. On the other hand, few programmes designed to reduce health inequalities have been formally evaluated using cost effectiveness analysis. We conclude that fairness is likely to be the most influential argument in favour of acting to reduce disparities in health, but the concept of equity is contested and susceptible to different interpretations. There is persuasive evidence for some outcomes that reducing inequalities will diminish "spill over" effects on the health of society at large. In principle, you would expect that differences in health status that are not biologically determined are avoidable. However, the mechanisms giving rise to inequalities are still imperfectly understood, and evidence remains to be gathered on the effectiveness of interventions to reduce such inequalities.

Psychosocial risk factors, inequality and self-rated morbidity in a changing society

The aim of this study was to analyse the interaction of social, economic, psychological and self-rated health characteristics of the Hungarian population in representative, stratified nation-wide samples during the period of sudden political-economic changes. In 1988 20,902 and in 1995 12,640 persons, representing the Hungarian population over the age of 16 by age, sex and place of residence were interviewed. Self-rated morbidity characteristics, shortened Beck Depression Inventory, hopelessness, hostility, ways of coping, social support, control over working situation and socioeconomic characteristics were examined. Age dependent changes could be observed between 1988 and 1995 with increasing depressive symptomatology, hopelessness, lack of control over working situation in the population above 40 years, while in the younger population improvements in depressive symptomatology could be seen. According to hierarchical loglinear analysis, depressive symptom severity mediates between relative socioeconomic deprivation and higher self-rated morbidity rates, especially among men. Depressive symptomatology is closely connected with hostility, low control in working situation, low perceived social support and emotional ways of coping. A vicious circle might be hypothesised between socially deprived situation and depressive symptomatology, which together has a major role in higher self-rated morbidity rates.

Long-term prognosis and incidence of acute myocardial infarction in patients on chronic hemodialysis. The Okinawa Dialysis Study Group

Mortality from cardiovascular disease is high in chronic dialysis patients. We observed the occurrence of acute myocardial infarction (AMI) in the chronic dialysis population in Okinawa, Japan. A total of 3,741 chronic dialysis patients (2,073 men, 1,668 women) were followed up for 10 years from April 1, 1988, to March 31, 1998. Only definite cases of AMI were registered. Data were compared with AMI registry data obtained from the general population of the same district. The total duration of observation was 15,748.8 patient-years. During the study period, 61 patients (40 men, 21 women) had AMI. The incidence of AMI was 3.9/1,000 patient-years (men, 4.4/1,000 patient-years; women, 3.1/1,000 patient-years). Twenty-four percent of the AMI cases occurred at 12 months after starting dialysis therapy. Mean age at onset of AMI was 60.9 +/- 11. 4 (SD) years; 58.9 +/- 11.4 years in men and 64.7 +/- 10.7 years in women. Survival rates after AMI were 50.8% at 1 month, 45.0% at 6 months, 36.5% at 12 months, and 13.0% at 44 months. Patients with diabetes mellitus (DM) had a greater incidence of AMI and a worse prognosis than patients without DM. The long-term prognosis of AMI was poor in chronic dialysis patients.

Health and rapid economic change in the late twentieth century

Rapidly expanding economies, such as the post-war Tiger Economies, are associated with increasing health and rapidly contracting economies, such as Central and Eastern Europe in the early 1990s, are associated with declining health. In Central and Eastern Europe health decline in association with economic contraction has been mediated by changes in income distribution and, also, by health-determining aspects of civil society. The nations of Central and Eastern Europe are an example of swift economic and political transformation occurring concurrently with economic decline; with increasing disparity in income distributions; and with high levels of distrust in civil institutions. Concurrent with these declines was a marked reduction in health status, described here in terms of life expectancy. Conversely, the nations of Southeast Asia experienced rapid economic growth and increasing life expectancies. Though data are scarce, the experience of the Tiger Economies appears to be one of economic growth; a virtuous cycle of increased investment in education and housing; and increasing parity in income distribution based upon a relatively equitable distribution of returns on education.

Nutrition, oxidative damage, telomere shortening, and cellular senescence: individual or connected agents of aging?

There is substantial and long-standing literature linking the level of general nutrition to longevity. Reducing nutrition below the amount needed to sustain maximum growth increases longevity in a wide range of organisms. Oxidative damage has been shown to be a major feature of the aging process. Telomere shortening is now well established as a key process regulating cell senescence in vitro. There is some evidence that the same process may be important for aging in vivo. Very recently it has been found that oxidative damage accelerates telomere shortening. It is therefore possible for us to propose as an outline hypothesis that the level of nutrition determines oxidative damage which in turn determines telomere shortening and cell senescence and that this pathway is important in determining aging and longevity in vivo. We also propose that telomeres in addition to their well-recognized role in "counting" cell divisions are also, through their GGG sequence, important monitors of oxidative damage over the life span of a cell. This may explain the evolutionary conservations of this triplet in the repeat telomere sequence unit.

Social determinants of health: from observation to policy

Differences in the health of individuals reflect inherent features of the societies in which they live. The way a society organizes itself and delivers wellbeing to its members are major determinants of health. Social, economic and political factors have an important influence on health and longevity. Social position and lifestyle only partially explain ill health. Psychosocial factors, such as a sense of isolation, deprivation or loss of control, are also important. Governments can reduce health inequalities by ensuring that all policies are assessed for their potential impact on the health of all sectors of society.

Food and nutrient intakes and overall survival of elderly Japanese

As part of the International Union of Nutritional Sciences (IUNS) Food Habits in Later Life Project, a group of 89 free-living Japanese aged 70 years and over (43 men and 46 women) residing in semiurban Okazaki, located in the middle of Honshu Island in Japan, were studied. They were followed up in order to determine whether nutrition plays a role in Japanese longevity. Information on food and nutrient intake was collected at study entry. During 55 months follow-up, eight men and five women died. The consumption of various food groups, after adjustment for energy intake to 10.5 MJ for men and 8.4 MJ for women, was similar for survivors and deceased, but there was a greater consumption of mushrooms and fats and oils among the survivors (p<0.05). Furthermore, survivors had a higher intake of total n-3 fatty acids, especially alpha-linolenic acid, compared with the deceased (p<0.05). Subjects who were not chronically energy deficient (BMI >= 18.5 kg/m2) showed a better survival probability with a higher intake of total n-3 fatty acids (>= 2.1 g/day, 25th percentile). A similar result for total n-3 fatty acids and alpha-linolenic acid was found using Cox proportional hazards analyses adjusted for age, gender and smoking status (p<0.05). After adjustment for bodyweight, the conditionally essential amino acid tyrosine was higher in women who survived (p<0.05). These findings suggest that the intake of n-3 fatty acids and of certain amino acids might be particularly important in elderly people for living longer.

Low serum cholesterol as a risk factor for hemorrhagic stroke in men: a community-based mass screening in Okinawa, Japan

The relation between the level of total serum cholesterol and stroke is controversial. The relation between serum total cholesterol and subtypes of stroke was examined in the participants of a community-based mass screening program in Okinawa, Japan. A total of 38,053 subjects, whose serum level of cholesterol had been determined during a mass screening carried out in 1983, were examined to see whether they had experienced stroke during a 3-year period from 1988 to 1991. Of them, 315 subjects aged 33-93 years (174 men, 141 women) had had a stroke during that period. The types of stroke were cerebral infarction in 164, cerebral hemorrhage in 111, subarachnoid hemorrhage in 19, and others in 21. In men, the odds ratio of cerebral hemorrhage was 0.71 (95% confidence interval, 0.55-0.95), and the odds ratio of cerebral hemorrhage associated with serum level of cholesterol < or =167 mg/dl, 168-191 mg/dl, 192-217mg/dl, and > or =218mg/dl were 1.00 (reference), 0.70 (0.38-1.30), 0.77 (0.55-1.08), 0.73 (0.56-0.96), respectively. Lower serum cholesterol was an independent predictor of cerebral hemorrhage in men.

Socioeconomic differences in health indices, social networks and mortality among Swedish men. A study of men born in 1933

BACKGROUND

In previous survey we found large socioeconomic differences in mortality among urban Swedish men which remained unexplained after controlling for smoking and standard coronary risk factors. The present analysis was undertaken in order to investigate a broader set of possible explanatory factors in another cohort of Swedish men.

STUDY POPULATION AND METHODS

Occupation was coded into five occupational classes for 717 of 776 participant men from a random population sample of 1016 men who were born in 1933. All were living in Göteborg and were 50 years old at the baseline examination. After 12 years' follow-up, 68 of the 717 men had died (9.5%).

RESULTS

Low occupational class was associated with a higher prevalence of smoking at baseline, but no association was found with systolic blood pressure, body mass index, waist to hip ratio, serum triglycerides or serum cholesterol. Subjects from higher socioeconomic strata were taller, had higher maximum peak respiratory flow, lower plasma fibrinogen and lower body temperature. Low occupational class was associated with low social integration, low home activity levels, low levels of activity outside home and low social activity levels (p = 0.001 for all) and with low emotional support (p = 0.018). There were also associations between low occupational class and poor self-perceived health, as well as with several cardiovascular symptoms. During 12 years' follow-up, there was a graded and inverse relationship between occupational class and mortality from all causes. The highest mortality was found among the men who could not be classified (23 per 1,000 person years) Of the men in the lowest occupational class, 12 per 1,000 died, compared to 3 per 1,000 in the highest class (relative risk 3.7 (1.4-9.8)). After controlling for smoking, the relative risk decreased to 3.2 (1.2-8.6) and after further adjustment for emotional support, self-perceived health, activity level at home, and peak expiratory flow, the relative risk was still twofold but not significantly so (RR 2.1 (0.8-5.8)).

CONCLUSION

We were able to confirm earlier results as to the wide mortality differentials in urban middle-aged men in Sweden. There were also large differences in several other factors, including constitutional factors, health variables, lifestyle and social support indices, which explained important parts of the social mortality gradient, the most prominent being smoking, respiratory function, social network factors and subjective health.

Menopause: lessons from anthropology

OBJECTIVES

In North America and Europe, it is usually assumed that biological changes associated with the end of menstruation and the onset of specific diseases commonly associated with the postmenopausal condition are universal. Using an anthropological approach in which menopause is understood as a concept that is historically and culturally produced, an argument is made for additional systematic investigation of what protects the majority of women from distress at menopause, and what factors contribute to a healthy old age.

METHOD

Survey research based on questionnaire responses, together with open-ended interviews and textual analyses, were used.

RESULTS

Differences are demonstrated in postmenopausal experiences and symptom reporting in Japan as compared with Canada and the United States. Reporting of hot flashes and nights sweats is significantly lower in Japan. These findings, together with the well established figures about greater longevity and lower incidence of heart disease, breast cancer, and osteoporosis in Japan, compared with North America, indicate that cultural and biological variables act in concert to produce this variation. Theories about the evolution of menopause and demographic data on aging are also discussed. This data challenges the widely held assumption that populations of postmenopausal women only recently have come into existence because of cultural and technological interventions.

CONCLUSIONS

Postmenopausal women have been present in human populations since homo sapiens first evolved. Culturally mediated life styles affect both the menopausal experience and the health of women as they age. Additional investigations are needed.

Japan's egalitarian health care system: a brief historical analysis

Japan is one of several East Asian countries that share an ethical system of mutual support. A review of Japan's health care system reveals a strong egalitarian ethos often considered unique by outside observers.

Feast and famine: socioeconomic disparities in global nutrition and health

OBJECTIVE

To review current information on under- and over-malnutrition and the consequences of socioeconomic disparities on global nutrition and health.

DESIGN

Malnutrition, both under and over, can no longer be addressed without considering global food insecurity, socioeconomic disparity, both globally and nationally, and global cultural, social and epidemiological transitions.

SETTING

The economic gap between the more and less affluent nations is growing. At the same time income disparity is growing within most countries, both developed and developing. Concurrently, epidemiological, demographic and nutrition transitions are taking place in many countries.

RESULTS

Fully one-third of young children in the world's low-income countries are stunted because of malnutrition. One-half of all deaths among young children are, in part, a consequence of malnutrition. Forty percent of women in the developing world suffer from iron deficiency anaemia, a major cause of maternal mortality and low birth weight infants. Despite such worrying trends, there have been significant increases in life expectancy in nearly all countries of the world, and continuing improvements in infant mortality rates. The proportion of children malnourished has generally decreased, although actual numbers have not in sub-Saharan Africa and south Asia. Inequalities are increasing between the richest developed countries and the poorest developing countries. Social inequality is an important factor in differential mortality in both developed and developing countries. Many countries have significant pockets of malnutrition and increased mortality of children, while obesity and non-communicable diseases (NCDs) prevalences are increasing. Not infrequently it is the poor and relatively disadvantaged sectors of the population who are suffering both. In the industrialized countries, cardiovascular disease incidence has declined, but less so in the poorer socioeconomic strata.

CONCLUSIONS

The apparent contradictions found represent a particular point in time (population responses generally lag behind social and environmental transitions). They do also show encouraging evidence that interventions can have a positive impact, sometimes despite disadvantageous circumstances. However, it seems increasingly unlikely that food production will continue to keep up with population growth. It is also unlikely present goals for reducing protein-energy malnutrition prevalence will be reached. The coexistence of diseases of undernutrition and NCDs will have an impact on allocation of resources. Action needs to be continued and maintained at the international, national and individual level.

Relationship between serum cholesterol and the risk of acute myocardial infarction in a screened cohort in Okinawa, Japan

Coronary heart disease (CHD) is rare in Japanese subjects and serum cholesterol levels are low. However, no data have been published relating the effect of serum cholesterol levels to the incidence of acute myocardial infarction (AMI) in Japan. Data from a large community-based mass screening registry are available for the geographically isolated island of Okinawa, Japan (1980 census, 1.11 million). A total of 38,053 participants (17,859 men and 20,194 women) whose serum cholesterol levels were determined in the 1983 mass screening were examined to determine whether they had experienced AMI. Every case of AMI that occurred during a 3-year period (1 April 1988 to March 1991) throughout Okinawa was recorded in a separate registry. The total number of cases of AMI was 1,021 (674 men and 347 women). Of these, 65 patients (41 men and 24 women) were identified by name, sex, birth date, and zip code in the mass screening registry. The cumulative incidence of AMI increased with the serum level of cholesterol: 42.1 (serum cholesterol < or = 167 mg/dl), 133.5 (serum cholesterol 168-191 mg/dl), 188.9 (serum cholesterol 192-217 mg/dl), and 323.0 (serum cholesterol > or = 218 mg/dl) per 100,000 screened subjects. Multiple logistic analysis was conducted to examine the effect of serum cholesterol on the risk of AMI with adjustment for other variables such as sex, age, systolic and diastolic blood pressure, and proteinuria. The adjusted odds ratio (95% confidence interval) of the observed serum levels of cholesterol was 1.66 (1.29-2.15) with a reference serum cholesterol level of < or = 167 mg/dl. The risk of AMI increased in proportion to the serum level of cholesterol. Serum cholesterol is an independent predictor of AMI in Okinawa, Japan.

Does prompt treatment of hypertension after blood pressure check-ups reduce morbidity of cerebrovascular diseases?

In Japan, more than 20 million people utilize blood pressure check-up services in their work places or communities every year. To examine the relationship between prompt treatment of hypertension after these blood pressure check-ups and the severity, age at onset, and type of cerebrovascular diseases in these patients, a study was performed with the cooperation of all 174 independent physicians, 17 hospitals, and 4 welfare homes in the city of N.. All patients aged 50 years or more who visited a physician during the study period in this city were included in the study (n=978). Information on hypertensive control before the onset of cerebrovascular diseases was obtained from 668 patients. The results suggests that for those who had received prompt treatment after early detection of hypertension, the disease was less severe and the onset of the disease was delayed. Among our subjects, 47% of the patients claimed to have received prompt treatment after detection of hypertension. As N. is an ordinary Japanese city in terms of the promotion of health check-up programs, this percentage suggests that blood pressure check-up programs for the early detection of hypertension throughout Japan may have contributed to an overall reduction in severity for almost half of the patients with cerebrovascular diseases.

Predictors of stroke in patients receiving chronic hemodialysis

To identify the risk factors of stroke in patients receiving maintenance hemodialysis, we conducted a prospective study on patients in Okinawa, Japan. Patients with end-stage renal disease who were treated with maintenance hemodialysis before the end of 1990 and were alive on January 1, 1991 (N = 1,243) were studied. Medical records and pertinent data as of January 1, 1991 were compiled. All occurrences of stroke were recorded throughout the follow-up period, and until the end of 1995. The duration of observation was 5,110.3 patient-years. A total of 90 cases of stroke were observed, including 63 (70.0%) cerebral hemorrhage, 20 (22.2%) cerebral infarction, and 7 (7.8%) subarachnoid hemorrhage. Multiple logistic analysis identified hypertension as an independent predictor of stroke, with an odds ratio of 2.38 and a 95% confidence interval from 1.26 to 4.50. The present study demonstrates that the high incidence of stroke is at least partially explained by insufficient control of hypertension. Every effort to control hypertension is warranted in chronic dialysis patients.

'Silent' cerebral infarction is associated with hypercoagulability, endothelial cell damage, and high Lp(a) levels in elderly Japanese

"Silent" lacunar stroke, often found in the elderly, has been proposed as a predisposing condition for clinically overt stroke. However, the risk factors related to this condition have not been studied thoroughly. We conducted brain magnetic resonance imaging and measured the levels of fibrinogen, molecular markers of coagulation activation [prothrombin fragment 1 + 2 (F1 + 2)] and endothelial cell damage [von Willebrand factor (vWF) and thrombomodulin], and lipid profiles including lipoprotein (a) [Lp(a)] in 178 asymptomatic, high-risk, Japanese subjects aged 44 to 93 years. We also studied 32 symptomatic patients with lacunar stroke (symptomatic lacunar group). The prevalence of silent lacunar stroke increased with age up to 85 years but decreased with age in those 85 years old and older. Of the 160 elderly subjects ( > or = 60 years) 84 (53%) had > or = 1 lacunar infarcts (silent lacunar group) and the remaining 76 were considered as the nonlacunar group. Fibrinogen and F1 + 2 levels in the silent lacunar group were significantly higher than those in the nonlacunar group (P < .01). Mean Lp(a) levels and the prevalence of subjects with an Lp(a) level > 30 mg/dL were significantly higher in the symptomatic lacunar group than the nonlacunar group (P < .05), whereas these levels in the silent lacunar group were intermediate to those of the other two groups. When we further classified the silent lacunar group into three subgroups based on the number of lacunes (few lacunes, 1 or 2; moderate number of lacunes, 3 or 4; and numerous lacunes, > or = 5), levels of Lp(a), F1 + 2, vWF, and thrombomodulin were significantly higher and Lp(a) levels > 30 mg/dL more common in the numerous-lacune than in the few-lacune subgroup. We conclude that silent lacunar stroke is often found in asymptomatic, high-risk, elderly Japanese patients and that silent multiple lacunar stroke is associated with hypercoagulability, endothelial cell damage, and high Lp(a) levels.