Trends in the incidence of stroke and cardiovascular risk factors on the isolated island of Okinawa: the Miyakojima study

Diverging Temporal Trends in Stroke Incidence in Younger vs Older People: A Systematic Review and Meta-analysis

Importance

Overall stroke incidence is falling in high-income countries, but data on time trends in incidence of young stroke (ie, stroke in individuals younger than 55 years) are conflicting. An age-specific divergence in incidence, with less favorable trends at younger vs older ages, might be a more consistent underlying finding across studies.

Objective

To compare temporal trends in incidence of stroke at younger vs older ages in high-income countries.

Data Sources

PubMed and EMBASE were searched from inception to February 2022. One additional population-based study (Oxford Vascular Study) was also included.

Study Selection

Studies reporting age-specific stroke incidence in high-income countries at more than 1 time point.

Data Extraction and Synthesis

For all retrieved studies, 2 authors independently reviewed the full text against the inclusion criteria to establish their eligibility. Meta-analysis was performed with the inverse variance-weighted random-effects model. Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline was followed.

Main Outcomes and Measures

The main outcome was age-specific divergence (<55 vs ≥55 years) in temporal trends in stroke incidence (relative temporal rate ratio [RTTR]) in studies extending to at least 2000. RTTRs were calculated for each study and pooled by random-effects meta-analysis, with stratification by administrative vs prospective population-based methodology, sex, stroke subtype (ischemic vs intracerebral hemorrhage vs subarachnoid hemorrhage) and geographical region.

Results

Among 50 studies in 20 countries, 26 (13 prospective population-based and 13 administrative studies) reported data allowing calculation of the RTTR for stroke incidence at younger vs older ages across 2 or more periods, the latest extending beyond 2000. Reported trends in absolute incidence of young individuals with stroke were heterogeneous, but all studies showed a less favorable trend in incidence at younger vs older ages (pooled RTTR = 1.57 [95% CI, 1.42-1.74]). The overall RTTR was consistent by stroke subtype (ischemic, 1.62 [95% CI, 1.44-1.83]; intracerebral hemorrhage, 1.32 [95% CI, 0.91-1.92]; subarachnoid hemorrhage, 1.54 [95% CI, 1.00-2.35]); and by sex (men, 1.46 [95% CI, 1.34-1.60]; women, 1.41 [95% CI, 1.28-1.55]) but was greater in studies reporting trends solely after 2000 (1.51 [95% CI, 1.30-1.70]) vs solely before (1.18 [95% CI, 1.12-1.24]) and was highest in population-based studies in which the most recent reported period of ascertainment started after 2010 (1.87 [95% CI, 1.55-2.27]).

Conclusions and Relevance

Temporal trends in stroke incidence are diverging by age in high-income countries, with less favorable trends at younger vs older ages, highlighting the urgent need to better understand etiology and prevention of stroke at younger ages.

Trends in surgical procedures for spontaneous intracerebral hemorrhage in Japan

OBJECTIVES

Minimally invasive surgery for spontaneous intracerebral hemorrhage (ICH) has become increasingly popular in recent years. However, there are no reports on the recent trends in surgical procedures for spontaneous ICH. To investigate current trends in surgical methods for spontaneous ICH using a nationwide inpatient database from Japan.

MATERIALS AND METHODS

Patients who underwent surgery for spontaneous ICH between April 2014 and March 2018 were identified in a nationwide inpatient database from Japan. We examined patient characteristics, diagnoses, types of surgery, complications, and discharge status.

RESULTS

We identified 21,129 inpatients who underwent surgery for spontaneous ICH. The procedures were as follows: 16,256 (76.9%) transcranial hemorrhage evacuations, 3722 (17.6%) endoscopic hemorrhage evacuations, and 1151 (5.4%) stereotactic aspirations of hemorrhage. Patients tended to receive transcranial hemorrhage evacuations in hospitals with fewer surgical cases. The proportions of endoscopic hemorrhage evacuations increased annually, whereas those of stereotactic surgery decreased. The proportions of transcranial surgery remained almost unchanged. Tracheostomy and hospitalization costs were lower in the stereotactic aspirations of hemorrhage group, and the proportions of reoperation were higher in the endoscopic hemorrhage evacuations group.

CONCLUSIONS

The use of endoscopic surgery for spontaneous ICH has increased in Japan. This study can form the basis of future clinical investigations into spontaneous ICH surgery.

Global Stroke Statistics 2019

BACKGROUND

Data on stroke epidemiology and availability of hospital-based stroke services around the world are important for guiding policy decisions and healthcare planning.

AIMS

To provide the most current incidence, mortality and case-fatality data on stroke and describe current availability of stroke units around the world by country.

METHODS

We searched multiple databases (based on our existing search strategy) to identify new original manuscripts and review articles published between 1 June 2016 and 31 October 2018 that met the ideal criteria for data on stroke incidence and case-fatality. For data on the availability of hospital-based stroke services, we searched PubMed for all literature published up until 31 June 2018. We further screened reference lists, citation history of manuscripts and gray literature for this information. Mortality codes for International Classification of Diseases-9 and International Classification of Diseases-10 were extracted from the World Health Organization mortality database for each country providing these data. Population denominators were obtained from the World Health Organization, and when these were unavailable within a two-year period of mortality data, population denominators within a two-year period were obtained from the United Nations. Using country-specific population denominators and the most recent years of mortality data available for each country, we calculated both the crude mortality from stroke and mortality adjusted to the World Health Organization world population.

RESULTS

Since our last report in 2017, there were two countries with new incidence studies, China (n = 1) and India (n = 2) that met the ideal criteria. New data on case-fatality were found for Estonia and India. The most current mortality data were available for the year 2015 (39 countries), 2016 (43 countries), and 2017 (7 countries). No new data on mortality were available for six countries. Availability of stroke units was noted for 63 countries, and the proportion of patients treated in stroke units was reported for 35/63 countries.

CONCLUSION

Up-to-date data on stroke incidence, case-fatality, and mortality statistics provide evidence of variation among countries and changing magnitudes of burden among high and low-middle income countries. Reporting of hospital-based stroke units remains limited and should be encouraged.

Risk Factors and Outcomes of Cerebral Stroke in End-Stage Renal Disease Patients Receiving Hemodialysis

OBJECTIVE

Dialysis patients have a higher incidence of stroke, and outcomes are often poor. Diabetic nephropathy (DN) is a stroke risk-factor, but the importance is unclear in dialysis patients. This study investigated the stroke features and risk factors in hemodialysis (HD) patients.

METHODS

All end-stage renal disease patients undergoing HD at Teraoka Memorial Hospital dialysis center were identified, with 195 recruited. Baseline clinical characteristics were collected, and the clinical outcomes and related factors of stroke in HD patients were retrospectively analyzed. The incidence rate of stroke and mortality were calculated using Kaplan-Meier survival analysis. Factors potentially related to stroke were analyzed by the log-rank test and Cox proportional hazards model for univariate and multivariate analysis.

RESULTS

In total, 21.0% (41 of 195) patients developed stroke. The incidence rates of stroke per 1000 patient-years were 53.6, 65.2, and 34.0 in all HD patients, DN patients, and non-DN patients, respectively. The cumulative incidence rates of stroke in all HD patients, DN patients, and non-DN patients per 5 years, and per 10 years were 22.6%, 43.5%; 28.8%, 59.6%; and 17.6%, 31.1%, respectively. The incidence rate of stroke in the DN patients was significantly higher than in the non-DN patients (P = .013). DN was the significant risk factor for stroke by multivariate analysis (hazard ratio 2.63, 95% confidence interval 1.08-7.85; P = .032).

CONCLUSIONS

This study revealed the trends of stroke in HD patients at a single institution in Japan. DN was shown to be a significant risk factor for stroke in HD patients.

Increased Stroke Burdens Among the Low-Income Young and Middle Aged in Rural China

Background and Purpose—

Although stroke in the young and middle aged accounts for 31% of all strokes in China, the disease burden is unknown. We aimed to determine the secular trends in stroke incidence and the transition of subtypes in rural China over a 24-year period.

Methods—

In 1992, 14 920 residents were recruited to participate in the Tianjin Brain Study. Stroke events and all deaths were registered annually. We assessed the trends in incidence of first-ever stroke, including intracerebral hemorrhage and ischemic stroke, among adults aged 35 to 64 years during 1992 to 1999, 2000 to 2007, and 2008 to 2015. The annual proportion of change in stroke incidence was evaluated from 1992 to 2015.

Results—

The age-standardized incidence of first-ever stroke per 100 000 person-years increased significantly, from 122 in 1992 to 1999, to 215.8 in 2000 to 2007, to 471.8 in 2008 to 2015. The incidence of first-ever stroke increased annually by 11.9% overall (12.4% in men, 9.0% in women, 8.7% for intracerebral hemorrhage, and 10.7% for ischemic stroke; P <0.001). The greatest increases were observed in adults aged 55 to 64 years, with an annual increase of 11.6% for ischemic stroke (10.8% in men and 6.9% in women). However, the proportion of intracerebral hemorrhage has not changed over the past 24 years.

Conclusions—

In contrast with that in developed countries, the burden of stroke in China originates primarily from young and middle-aged adults. Thus, control of risk factors in this population is required to reduce the future burden of stroke in China.

Global stroke statistics

Background Up to date data on incidence, mortality, and case-fatality for stroke are important for setting the agenda for prevention and healthcare. Aims and/or hypothesis We aim to update the most current incidence and mortality data on stroke available by country, and to expand the scope to case-fatality and explore how registry data might be complementary. Methods Data were compiled using two approaches: (1) an updated literature review building from our previous review and (2) direct acquisition and analysis of stroke events in the World Health Organization (WHO) mortality database for each country providing these data. To assess new and/or updated data on incidence, we searched multiple databases to identify new original papers and review articles that met ideal criteria for stroke incidence studies and were published between 15 May 2013 and 31 May 2016. For data on case-fatality, we searched between 1980 and 31 May 2016. We further screened reference lists and citation history of papers to identify other studies not obtained from these sources. Mortality codes for ICD-8, ICD-9, and ICD-10 were extracted. Using population denominators provided for each country, we calculated both the crude mortality from stroke and mortality adjusted to the WHO world population. We used only the most recent year reported to the WHO for which both population and mortality data were available. Results Fifty-one countries had data on stroke incidence, some with data over many time periods, and some with data in more than one region. Since our last review, there were new incidence studies from 12 countries, with four meeting pre-determined quality criteria. In these four studies, the incidence of stroke, adjusted to the WHO World standard population, ranged from 76 per 100,000 population per year in Australia (2009-10) up to 119 per 100,000 population per year in New Zealand (2011-12), with the latter being in those aged at least 15 years. Only in Martinique (2011-12) was the incidence of stroke greater in women than men. In countries either lacking or with old data on stroke incidence, eight had national clinical registries of hospital based data. Of the 128 countries reporting mortality data to the WHO, crude mortality was greatest in Kazhakstan (in 2003), Bulgaria, and Greece. Crude mortality and crude incidence of stroke were both positively correlated with the proportion of the population aged ≥ 65 years, but not with time. Data on case-fatality were available in 42 studies in 22 countries, with large variations between regions. Conclusions In this updated review, we describe the current data on stroke incidence, case-fatality and mortality in different countries, and highlight the growing trend for national clinical registries to provide estimates in lieu of community-based incidence studies.

Factors associated with visceral fat accumulation in the general population in Okinawa, Japan

AIM: To investigate the clinical and biochemical factors associated with visceral fat accumulation in the general population.

METHODS: We enrolled 1004 subjects who underwent a medical health checkup between April 2008 and March 2009. The medical health checkup included the following tests: Height, body weight, waist circumference (WC), systolic blood pressure, diastolic blood pressure, urinalysis, blood-cell counts, blood chemistry, electrocardiography, chest radiography, and abdominal computed tomography (CT) for visceral fat accumulation. The patients’ medical history and lifestyle factors were collected privately by nurses using a self-administered questionnaire, and they included questions regarding physical activity, sleep duration, dietary habits, smoking, and alcohol consumption. Visceral fat area (VFA) was defined as the sum of the intraperitoneal fat area at the level of the umbilicus with CT density in the range of -150 to -50 Hounsfield units.

RESULTS: The mean age and body mass index (BMI) of the study subjects were 57.0 years and 24.4 kg/m². In both male and females, VFA was significantly and positively correlated with WC (r = 0.532, P < 0.01; r = 0.612, P < 0.01). Subjects with high levels of VFA were primarily male with significantly higher age, height, body weight, BMI, systolic blood pressure (BP), diastolic BP, and hemoglobin in all subjects (P < 0.05). A multivariate logistic regression analysis revealed that VFA had a positive relationship with age ≥ 56, BMI ≥ 25 kg/m², and triglyceride level ≥ 149 in males (P < 0.05), whereas it had a positive relationship with age ≥ 58, BMI ≥ 24.4 kg/m², high-density lipoprotein cholesterol level < 40 mg/dL, and current drinking in females (P < 0.05).

CONCLUSION: These results suggest that gender differences exist in the clinical and biochemical parameters associated with visceral fat accumulation.

Trends in Incidence of Stroke and Transition of Stroke Subtypes in Rural Tianjin China: A Population-Based Study from 1992 to 2012

Objectives

The incidence of ischemic stroke has increased and that of hemorrhagic stroke has decreased in urban China; however, the trends in rural areas are unknown. We aimed to explore the secular trends in incidence and transition of stroke subtypes among rural Chinese.

Methods

This was a population-based stroke surveillance through the Tianjin Brain Study. A total of 14,538 residents in a township of Ji County in Tianjin, China participated in the study since 1985. We investigated the age-standardized stroke incidence (sex-specific, type-specific, and age-specific), the annual proportion of change in the incidence of stroke, and the proportion of intracerebral hemorrhage in the periods 1992–1998, 1999–2005, and 2006–2012, because the neuroimaging technique was available since 1992 in this area.

Results

The age-standardized incidence per 100,000 person-years increased significantly for both intracerebral hemorrhage (37.8 in 1992–1998, 46.5 in 1999–2005, and 76.5 in 2006–2012) and ischemic stroke (83.9 in 1992–1998, 135.3 in 1999–2005, and 238.0 in 2006–2012). The age-standardized incidence of first-ever stroke increased annually by 4.9% for intracerebral hemorrhage and by 7.3% for ischemic stroke. The greatest increase was observed in men aged 45–64 years for both stroke types (P < 0.001). The proportion of intracerebral hemorrhage was stable overall, increased among men aged 45–64 years, and decreased among men aged ≥65 years. The average age of intracerebral hemorrhage in men reduced by 7.5 years from 1992 to 2012.

Conclusion

The age-standardized incidence of main stroke subtypes increased significantly in rural China over the past 21 years; the overall proportion of intracerebral hemorrhage was stable, but the incidence increased significantly among middle-aged men. These findings imply that it is crucial to control stroke risk factors in middle-aged men for stroke prevention in future decades.

Stroke in Asia: geographical variations and temporal trends

Asian countries are in various stages of epidemiological transition and therefore exhibit a great diversity in disease patterns. Collectively, they comprise almost two-third of the world's total mortality due to stroke. The purpose of this review is to explore existing epidemiological data on stroke, highlight the temporal trends in stroke epidemiology in various regions of Asia and predict future patterns based on these observations. Our search revealed that there is a lack of good epidemiological data from most Asian countries. Whatever data exist are not comparable due to lack of standardised methodology for ascertaining stroke and its subtypes. For this and other reasons, these estimates exhibit country-to-country variation and also within-country variability. We have also reviewed temporal trends in stroke incidence and prevalence in 12 Asian countries and the evolution of stroke subtypes over the past two decades. Important observations include a rise in stroke incidence in most Asian countries, an earlier age at onset compared with the West, a relative increase in the proportion of ischaemic strokes and a decline in haemorrhagic strokes. Among ischaemic stroke subtypes, lacunar strokes, which were once the commonest variety, are now declining. Emerging data suggest that large artery atherosclerosis and in particular that of intracranial vessels is the predominant aetiology in most Asian countries. The review also identified important gender differences in terms of stroke risk factors, prevalence and outcomes. There is need for sound epidemiological data from most countries to understand the disease better and plan policy-level interventions to decrease the burden. We identify a need for standard format or guidelines for conducting stroke epidemiological studies especially in developing Asian countries. This region must be identified as a priority region for stroke-related interventions and preventive strategies by global healthcare authorities and organisations.

Global stroke statistics

In many countries, stroke is a lower priority than other diseases despite its public health impact. One issue is a lack of readily accessible comparative data to help make the case for the development of national stroke strategies. To assist in this process, we need to have a common repository of the latest published information on the impact of stroke worldwide. We aim to provide a repository of the most current incidence and mortality data on stroke available by country and illustrate the gaps in these data. We plan to update this repository annually and expand the scope to address other aspects of the burden of stroke. Data were compiled using two approaches: (1) an extensive literature review with a major focus on published systematic reviews on stroke incidence (between 1980 and May 14, 2013); and (2) direct acquisition and collation of data from the World Health Organization to present the most current estimates of stroke mortality for each country recognized by the World Health Organization. For mortality, ICD8, ICD9, and ICD10 mortality codes were extracted. Using population denominators crude stroke mortality was calculated, as well as adjusting for the World Health Organization world population. We used only the most recent year reported to the World Health Organization. Incidence rates for stroke were available for 52 countries, with some countries having incidence studies undertaken in more than one region. When adjusted to the World Health Organization world standard population, incidence rates for stroke ranged from 41 per 100 000 population per year in Nigeria (1971-74) to 316/ 100 000/year in urban Dar-es-Salaam (Tanzania). Some regions had three to fivefold greater incidence than other countries. Of the 123 countries reporting mortality data, crude mortality was greatest in Kazhakstan (in 2003). In many regions data were very old or nonexistent. Such country-level data are important for citizens, clinicians, and policy makers so that local and global strategies to reduce the overall burden of stroke can be implemented. Through this first annual review of country-specific stroke epidemiology, we hope to promote discussion and provide insights into the worldwide burden of stroke.

Trends in stroke survival incidence rates in older Australians in the new millennium and forecasts into the future

AIMS

The objective of this study is (i) to evaluate trends in the incidence rates of stroke survivors aged 60 years and older over a 11-year period in the Australian Capital Territory (ACT) and (ii) to forecast future trends in Australia until 2051.

METHODS

Analysis of age- and sex-specific standardized incidence rates of older first-ever stroke survivors in ACT from 1999-2000 to 2009-2010 and projections of number of stroke survivors (NSS) in 2021 and 2051 using 2 models based only on (i) demographic changes and (ii) assuming changing of both incidence rates and demography.

RESULTS

In the ACT in the first decade of the 21st century, the absolute numbers and age-adjusted standardized incidence rates of stroke survivors (measured as a function of age and period) increased among both men and women aged 60 years or older. The trend toward increased survival rates in both sexes was driven mainly by population aging, whereas the effect of stroke year was more pronounced in men compared with women. The absolute NSS (and the financial burden to the society) in Australia is predicted to increase by 35.5%-59.3% in 2021 compared with 2011 and by 1.6- to 4.6-fold in 2051 if current only demographic (first number) or both demographic and incidence trends (second number) continue.

CONCLUSIONS

Our study demonstrates favorable trends in stroke survivor rates in Australia in the first decade of the new millennium and projects in the foreseeable future significant increases in the absolute numbers of older stroke survivors, especially among those aged 70 years or older and men.