Stroke in China, 1986 through 1990

Prevalence and risk factors of stroke in a rural area of northern China: a 10-year comparative study

BACKGROUND AND AIMS

Stroke is currently the leading cause of death in China; however, the past decade has produced no new epidemiological studies of stroke. Therefore, the current study aimed to compare the prevalence and risk factors of stroke between 2010 and 2019.

METHODS

A comparative study was used to analyze the prevalence of risk factors for stroke in a population aged 65 years or older between 2010 and 2019. Demographic characteristics, risk factors, medical history, and other clinical characteristics were collected for all participants via door-to-door interviews and inpatient hospital records.

RESULTS

The standardized prevalence of stroke was 7.9% in 2010 and 14.2% in 2019 (p < 0.001). The prevalence of stroke was significantly higher in men than in women (p < 0.05) for all age groups. The risk factors of stroke were being male, hypertension, and diabetes mellitus in both 2010 and 2019. When comparing the risk factors between 2010 and 2019, these risk factors were statistically significantly more strongly associated with stroke in 2019 than in 2010.

CONCLUSION

The current study suggests that the prevalence of stroke increased nearly by twofold in a population aged 65 years or older within the past 10 years. Hypertension, diabetes mellitus, and being male were the primary risk factors. In addition, these factors were more significantly associated with stroke in 2019 compared to 2010.

Prevalence and Risk Factors of High-Risk Population for Stroke: A Population-Based Cross-Sectional Survey in Southwestern China

With the aging of the population and the change of lifestyle in China, the prevalence and risk factors of the high-risk population for stroke may change. However, few studies performed community-based high-risk stroke population surveys in China. Hence, we performed this multicenter, cross-sectional, and community-based survey in Sichuan of southwestern China, according to the China National Stroke Screening Survey (CNSSS) program in 2015. The residents aged ≥ 40 years volunteered to participate in the face-to-face survey in 8 communities in Sichuan. The 8 communities were selected using the cluster randomization method. Subjects with at least three of the eight stroke-related risk factors were classified as a high-risk population for stroke. Otherwise were classified as a low-risk population for stroke. Furthermore, 1,011 individuals were randomly selected among the low-risk population for stroke as controls. Among 16,892 participants, 2,369 (14.0%) were high-risk population for stroke. After full adjustments, all eight risk factors for stroke were significantly associated with the high-risk population for stroke (P < 0.001). The largest contributor was hypertension [population-attributable risk (PAR) 28.4%], followed by physical inactivity (PAR 14.2%), dyslipidemia (PAR 11.2%), overweight/obesity (PAR 9.4%), diabetes (PAR 7.2%), family history (PAR 6.8%), smoking (PAR 5.9%), and atrial fibrillation (PAR 3.5%). Carotid atherosclerosis was more serious in the high-risk population for stroke than in controls (P < 0.05). The prevalence of the high-risk population for stroke was high in southwestern China. Hypertension, physical inactivity, and dyslipidemia were stronger contributors for the high-risk population for stroke. Individual-level and population-level interventions for these leading risk factors are very important for the primary prevention of stroke.

The prevalence of stroke and related risk factors among residents aged ≥ 40 years in Chongqing, Southwest China

Background

China bears the largest global stroke burden, yet little is known about its rates in Chongqing, southwest China. We aimed to investigate the prevalence and related risk factors for stroke in Chongqing, and to provide evidence for improved formulation of targeted primary preventive measures for stroke.

Methods

In 2015, a cross-sectional study was conducted in Nan’an district, Chongqing. Participants responded to a questionnaire surveying general information and common risk factors for stroke, and related physical examinations were conducted.

Results

Of 25,000 people aged ≥ 40 years who were investigated, 24,859 participants completed the questionnaire and underwent the physical examination. The crude prevalence rate for stroke was 1.71%, and was higher in men than in women (1.9% versus 1.6%). Prevalence rates increased with age (p < 0.001). Multiple logistic regression analysis indicated that too little exercise, hypertension, family history of stroke, and history of transient ischemic attack were stroke risk factors among three groups (men, women, and total participants; all p-values < 0.05). Smoking was a risk factor for men (odds ratio 2.77; 95% Cl 1.46–5.28) and having only attained a primary school or lower education level was a risk factor for women (p < 0.05).

Conclusions

These findings suggest that controlling stroke risk factors for stroke prevention is still crucial. Moreover, this study provides comprehensive resource data for further stroke research in southwest China.

Prevalence of stroke and stroke related risk factors: a population based cross sectional survey in southwestern China

Background

Stroke and its risk factors epidemiological survey can help identify individuals at higher risk and therefore promote stroke prevention strategies. The aim of this study was to estimate the current prevalence of stroke and high risk stroke population, and evaluate stroke associated risk factors in southwestern China.

Methods

This was a multi-center, cross sectional survey in southwestern China from May 2015 to September 2015. The eight communities were selected at random, and 17,413 residents aged ≥40 years volunteered to participate in this survey. Data were collected through face-to-face survey using a structured questionnaire. Five hundred twenty-one participants with incomplete questionnaires on stroke history or risk factors records were excluded.

Results

A total of 16,892 people included in analysis. The overall prevalence of stroke was 3.1% (95% CI 2.6–3.9%), 17.1% of participants were the high risk stroke population. After full adjustments, hypertension, diabetes, dyslipidemia, overweight, lack of exercise and family history of stroke were significantly associated with overall stroke and ischemic stroke. The largest contributor was hypertension (population-attributable risk 23.6%), followed by dyslipidemia, physical inactivity, family history of stroke, diabetes, and overweight. However, only hypertension (OR = 3.66, 95% CI 1.82–8.23) was significantly associated with hemorrhagic stroke.

Conclusions

The prevalence of stroke and high risk stroke population was high among adults aged ≥40 years in southwestern China. Hypertension, dyslipidemia and lack of exercise were stronger contributors for stroke, these findings suggest that individual-level and population-level interventions for these leading risk factors are necessary to prevent stroke.

Stroke epidemiology and stroke policies in China from 1980 to 2017: A systematic review and meta-analysis

Background

Stroke is the leading cause of death and years of life lost in China, and this problem is growing because stroke risk factors such as hypertension and hypercholesteremia have been on the rise as China experiences the demographic transition. The Chinese government has created public health initiatives in the form of guidelines, policies and programs to combat this problem, but the dissemination and effectiveness of these policies are not well known.

Aims

The aim of this study was to determine trends in stroke incidence, prevalence, and stroke-related mortality in China and to report these trends in the context of stroke initiatives that have been enacted by the Chinese government.

Summary of review

We systematically reviewed articles on stroke rates and stroke initiatives from 1980 to 2017. A meta-regression including 11 studies showed that stroke incidence remained stable at 128.3 per 100,000 per year from 1980 to 2005 and has increased by 21.3 per 100,000 per year since then to 298.7 per 100,000 per year in 2013. A meta-regression including seven studies demonstrated a gradual decline in stroke-related mortality by 6.5 per 100,000 per year since 1980 (a decline from 369.2 in 1980 to 154.7 per 100,000 per year in 2013). Average stroke prevalence was 898.4 per 100,000 over the entire time-period. Limitations included heterogeneity between the studies. We identified 12 stroke initiatives, the first of which was enacted in 2006.

Conclusions

Despite numerous public health initiatives aimed at combating stroke that started in 2006, stroke incidence in China has increased over the last decade, likely as a result of aging and urbanization of the Chinese population.

The Epidemiological Characteristics of Stroke in Hunan Province, China

Previous studies have shown that Hunan Province has a high incidence of stroke and a high proportion of intracerebral hemorrhage (ICH). Considering the changes over the past three decades, little is known about the current epidemiological characteristics of stroke in Hunan Province. In 2013, a cross-sectional study was conducted at seven national disease surveillance points (DSPs) in Hunan Province. A multistage cluster sampling method was used to select a representative sample. A total of 21,156 participants aged 20 years and older were examined. Among the 21,156 participants, the number of prevalent strokes, incident strokes and deaths was 307, 87, and 36, respectively. The 2010 China census-standardized prevalence, incidence and mortality were 1191.0 per 100,000 people [95% confidence interval (CI) 1044.8-1337.2], 333.6 per 100,000 person-years (95% CI 255.7-411.5) and 129.7 per 100,000 person-years (95% CI 81.1-178.3), respectively. Ischemic stroke (IS), ICH, subarachnoid hemorrhage (SAH), and stroke of undetermined type (UND) constituted 50.6, 41.4, 5.7, and 2.3% of all incident stroke cases, respectively. Tianxin, Liuyang, Wuling, and Hongjiang have high proportions of ICH (61.5, 58.3, 60, and 50%, respectively). Hypertension is the most common risk factor for prevalent stroke (71.34%), followed by smoking (30.62%) and alcohol use (25.73%). In conclusion, Hunan Province has an extremely heavy stroke burden. The high proportion of ICH is not limited to the Changsha community; it represents an important issue for all of Hunan Province.

Prevalence of stroke and associated risk factors: a population based cross sectional study from northeast China

OBJECTIVES

Epidemiological studies aimed at stroke and its risk factors can help identify persons at higher risk and therefore promote stroke prevention strategies. We aimed to explore the current prevalence of stroke and its associated risk factors in northeast China.

DESIGN

Population based cross sectional study.

SETTING

Data were collected using a structured precoded questionnaire designed by the Stroke Screening and Prevention Programme of the National Health and Family Planning Commission of China, between January and March 2016.

PARTICIPANTS

4100 permanent residents, aged 40 years or older, who had lived in Dehui City of Jilin Province for more than 6 months volunteered to participate in the survey, with a response rate of 92.2%. For the purpose of the present analysis, 48 subjects were excluded due to missing values, giving a total of 4052 people included in this analysis.

MAIN OUTCOME MEASURE

The questionnaire included demographic characteristics, stroke related behavioural factors, personal and family medical history of stroke, physical examination and laboratory testing.

RESULTS

The overall prevalence of stroke in Jilin Province was 7.2% (95% CI 6.3% to 8.2%). Of all stroke cases, 91.7% (95% CI 87.4% to 94.6%) were ischaemic stroke and 8.3% (95% CI 5.4% to 12.6%) were haemorrhagic stroke. The prevalence rates of dyslipidaemia, smoking and hypertension were ranked as the top three cerebrovascular risk factors and were 62.1%, 61.8% and 57.3%, respectively. We found that hypertension, dyslipidaemia and lack of exercise were associated with ischaemic stroke. However, only hypertension (OR=4.064, 95% CI 1.358 to 12.160) was significantly associated with haemorrhagic stroke.

CONCLUSIONS

The prevalence of stroke, especially ischaemic stroke, and associated cerebrovascular risk factors among adults aged 40 years or older in northeast China were high. A higher regional prevalence of hypertension, dyslipidaemia and lack of exercise may be responsible.

Sex Differences Do Not Exist in Outcomes among Stroke Patients with Intracranial Atherosclerosis in China: Subgroup Analysis from the Chinese Intracranial Atherosclerosis Study

BACKGROUND

To date, sex difference in outcomes among patients with intracranial atherosclerosis (ICAS) has rarely been discussed in China as well as in the world. This study aimed to estimate the sex difference in outcomes among patients with ICAS in Chinese cerebral ischemia patients.

METHODS

We analyzed 1,335 men and women with ICAS who were enrolled in the Chinese Intracranial Atherosclerosis study. They were followed-up for ischemic stroke recurrence, any cause of death, cerebral vascular events (including transient ischemic attack, ischemic and hemorrhagic stroke), combined end points (including cerebral vascular events, angina or myocardial infarction, pulmonary embolism, peripheral vascular events), and unfavorable outcome (modified Rankin scale score of 3-6) at 1 year.

RESULTS

During the follow-up period, 59 (13.44%) combined end points were documented in women and 107 (11.94%) in men. Of the combined end points, 47 were recurrent ischemic stroke events (14 in women and 33 in men), and 51 other causes of deaths (24 in women and 27 in men). There were 349 unfavorable end points (117 in women and 232 in men). The cumulative probability of death was higher in women, but after adjusting for age, diabetes mellitus, hypertension, family history of stroke, current smoker, heavy drinking, hyperhomocysteinemia, and heart disease, there was no significant difference. There was also a lack of difference in 1-year ischemic stroke recurrence, cerebral vascular events, combined end points, and unfavorable outcome between women and men at 1 year.

CONCLUSIONS

These results suggest no sex difference in outcome among patients with ICAS in Chinese cerebral ischemia patients.

Prevalence of stroke and associated risk factors among middle-aged and older farmers in western China

Objectives

China has the world’s largest population and the stroke has become the leading cause of death in recent years. The purpose of this study was to explore the associations between hypertension, family history of stroke, diabetes mellitus, obesity and stroke among middle-aged and older farmers of western China. A population-based study was conducted from June 2014 to April 2015 in Shaanxi and Sichuan provinces.

Methods

Twenty thousand five hundred twenty-five Chinese middle-aged and older farmers (≥40 years) were recruited to the Qinling-Daba Mountains Region Stroke Study. A structured-questionnaire was used to collect data through face-to-face interviews. Demographic characteristics, risk factors, medical history, and other clinical characteristics were recorded for all participants. The association between hypertension, family history of stroke, diabetes mellitus, obesity and stroke were analyzed by using univariate and multivariate logistic regression analysis.

Results

The stoke prevalence rate was 1380/100,000 in middle-aged and older farmers of western China. The difference in hypertension, diabetes mellitus, obesity and family history between different age groups had statistical significance (p < 0.05). The prevalence rate of hypertension and family history of stroke were higher in male population than in the female population. The difference was statistically significant (p < 0.05). Univariate logistic regression analysis demonstrated age, gender, hypertension, obesity and family history of stroke were stroke risk factors (p < 0.05). Multivariate logistic regression analysis revealed that the odds ratios of family history of stroke, obesity and hypertension were 7.177, 4.389 and 3.647 respectively.

Conclusions

Family history is the strongest stroke risk factor in middle-aged and older farmers of western China.

Stroke and Thrombolysis in Developing Countries

Summary of review

The epidemiology of stroke is well investigated in the developed world; however, in the developing world stroke is less well documented. Most of the available stroke data from these countries are hospital-based. Stroke thrombolysis is currently used in few developing countries like Brazil, Argentina, Senegal, Iran, Pakistan, China, Thailand, and India. The two main barriers for implementation of thrombolysis therapy in developing countries are the high cost of tissue plasminogen activator and lack of proper infrastructure. Most of the centers with the infrastructure to deliver thrombolysis for stroke are predominantly private sector, and only available in urban areas.

Conclusion

Until a more cost-effective thrombolytic agent and the proper infrastructure for widespread use of thrombolysis therapy are available, developing nations should focus on primary and secondary stroke prevention strategies and the establishment of stroke units wherever possible. Such multi-faceted approaches will be more cost-effective for developing countries than the use of thrombolysis.

The Epidemiology of Stroke in the East Asian Region: A Literature-Based Review

Stroke is a leading cause of morbidity and mortality in the developed world. Our objective was to review comparable studies of stroke incidence, prevalence, and subtypes in the East Asian region. English language epidemiologic studies of stroke published from 1984 through 2004 were identified for the East Asian region (China, Hong Kong, Taiwan, Japan, North and South Korea and the ASEAN countries). The Sudlow–Warlow criteria were modified to identify comparable studies. Stroke epidemiology is relatively well characterized in China, Taiwan, and Japan; however, little information is available for other countries. Four studies of stroke incidence, from China, Taiwan, and Japan, were identified, which reported a total of 4995 first-ever stroke events. There was an over twofold difference in the age-adjusted incidence of stroke between the Chinese Seven Cities and Okinawa study (483 vs 201 per 100 000). The 1-month case fatality rate ranged from 12·7% to 17·3%. Only one population-based study on stroke prevalence, from Taiwan, was identified: Studies show the relatively high proportion of hemorrhagic stroke (30%). Stroke epidemiology is relatively well characterized in China, Japan, and Taiwan but not in other countries in the region. More recent data are needed to monitor stroke prevention efforts and guide planning of health care resources in the region.

Ten-year trends in stroke admissions and outcomes in Canada

Background

We analyzed a 10-year stroke administrative dataset to examine trends in admissions, mortality, and discharge destination in Canada.

Methods

We conducted an analysis of hospital administrative data from April 1st 2003 to March 31st 2013 from the Canadian Institute of Health Information’s Discharge Abstract Database. Ten-year trends for population-based age- and sex-standardized admission rates were calculated. We reviewed 10-year trends in absolute stroke admissions for differences between provinces and age groups. Stroke 30-day in-hospital mortality rates were calculated and adjusted for sex, age, stroke type and comorbidities. We documented changes in discharge location for ischemic and hemorrhagic stroke patients discharged from acute care.

Results

The rate of hospital admissions has declined from 140.2 to 117.5 (per 100,000 people). The number of absolute stroke admissions within provinces increased in Alberta and British Columbia (21.7% and 16.2% respectively). The proportion of stroke patients aged 40-69 years old increased by 4.8% (p<0.0001) over the 10 years, whereas the proportion aged over 70 decreased by 4.9% (p<0.0001). Risk-adjusted 30-day in-hospital mortality decreased from: 18.5% to 14.9% for all strokes; 15.2% to 12.1% for ischemic strokes; 35.6% to 29.7% for intracerebral hemorrhage; and 25.1% to 18.0% for subarachnoid hemorrhage. The absolute increase in patients requiring inpatient and outpatient support increased by 4% (p<0.0001).

Conclusion

The rate of admissions for stroke is decreasing but there is an increase in stroke admissions for younger patients. In-hospital mortality is decreasing; fewer patients are going directly home without services and more are requiring support services.

Establishment of Population-Based Stroke Registry in Ludhiana City, Northwest India: Feasibility and Methodology

Background/Aims: The Indian Council of Medical Research (ICMR) initiated the Task Force Project to evaluate the feasibility of conducting a population-based stroke registry in Ludhiana city, Punjab, Northwest India. Methods: All first-ever, stroke patients over 18 years from the city of Ludhiana were included in the study from March 26th 2010 to March 25th 2011. Stroke information was collected based on the WHO STEPS approach from the participating hospitals, scan centres and doctors. Modified Rankin Scale (mRS) was administered by telephonic interview at 28 days after stroke. The information on stroke deaths was obtained from the Municipal Corporation (MC) office. Results: A total of 905 first-ever stroke patients were documented. After excluding duplicate cases and patients from outside the city, 493 patients were included. The practical issues identified in data collection from these centres were reluctance to take informed consent, lack of willingness to share the data, difficulty to identify key persons from each centre, retrieving medical records from public hospitals and poor documentation of deaths in MC office. Conclusion: Population-based stroke registry was feasible in an urban population with the above methodology. The issues related to feasibility were identified and necessary changes were made for the main phase of the registry.

Differences in ischemic and hemorrhagic recurrence rates among race-ethnic groups in the PRoFESS secondary stroke prevention trial

BACKGROUND AND AIMS

Epidemiological studies show that vascular risk factors are the same across the world but their effect vary between different race-ethnic groups. However, few studies have evaluated differences in recurrent stroke rates in various race-ethnicities. In >20 000 patients spanning 35 countries encompassing most race-ethnicities, we evaluated the incidence of ischemic and hemorrhagic strokes and myocardial infarction in patients within the context of the largest secondary stroke prevention trial (Prevention Regimen for Effectively Avoiding Secondary Strokes) to identify any significant differences.

METHODS

There were 20 332 patients with a recent ischemic stroke randomized in a factorial design to receive the antiplatelet agent clopidogrel vs. aspirin plus extended-release dipyridamole, and 80 mg of the anthypertensive telmisartan vs. placebo. The primary outcome for the trial was the time to any recurrent stroke. Statistical analysis was used to detect race-ethnic differences in recurrent vascular events.

RESULTS

Mean patient age was 66 (±8·6) years and 36% were women. The study included 58% European/Caucasian, 33% Asians, 5% Latin/Hispanic, and 4% Black African. There were 74% of patients that were hypertensive, and average systolic and diastolic blood pressure was 144·1/83·8 mmHg. There was at least one significant difference in the overall test of all race-ethnic groups in myocardial infarction and symptomatic intracerebral hemorrhage occurrence. In the Kaplan-Meier hemorrhage and stroke-free survival curves, Asians showed a significantly higher recurrence of ischemic stroke risk in the 135-150 mmHg and greater than 150 mm Hg blood pressure groups, and a greater risk of hemorrhage recurrence in the greater than 150 mmHg blood pressure group.

CONCLUSIONS

We found a significant difference in myocardial infarction and symptomatic intracerebral hemorrhage recurrence among different race-ethnic groups. The risk of recurrent ischemic and hemorrhagic stroke was greater in Asians with high blood pressure.

Incidence and trends of stroke and its subtypes in Changsha, China from 2005 to 2011

During the 1990s no significant changes were found for the high incidence of ischemic stroke (IS) in Changsha, in contrast to the increase observed in Beijing and Shanghai. However, the epidemiological patterns of stroke may change with economic development. This study aimed to examine the characteristics of stroke incidence transition in Changsha from 2005 to 2011. In 2007 two communities with a registered population of about 100,000 were selected and data from stroke patients who presented between 2005 and 2007 were retrospectively collected from January to June 2008. From January to December 2007 a stroke surveillance network was established and stroke patients who presented between 2008 and 2011 were prospectively registered. From 2005 to 2011 the mean annual age-adjusted incidence of first-ever stroke was 168.5/100,000 (95% confidence interval [CI] 159.0-178.0/100,000), with 189.3/100,000 (95% CI 175.1-178.0/100,000) for men and 148.7/100,000 (95% CI 136.0-161.4/100,000) for women. The mean annual age-adjusted incidence of IS, intracranial hemorrhage and subarachnoid hemorrhage was 72.6/100,000 (95% CI 66.3-78.9/100,000), 85.1/100,000 (95% CI 78.3-91.9/100,000) and 9.4/100,000 (95% CI 7.1-11.7/100,000), respectively. During the study period, the age-adjusted incidence of stroke increased at an annual rate of 3.7% (p=0.001); at 4.2% for men (p=0.001) and 3.1% for women (p=0.026). The age-adjusted incidence of IS increased at an annual rate of 3.5% (p=0.003) but no significant changes were seen for hemorrhagic stroke. Characteristics of stroke incidence transition may reflect underlying changes in risk factors and there is an urgent need to identify these factors and launch appropriate public health campaigns.

Epidemiological factors of stroke: a survey of the current status in china

Stroke is the leading cause of death in China and confers a huge burden and effort on patients and health professionals. China has the world's largest population and has been experiencing a rapid economic development. In this article, we review the current status of stroke epidemiological features and risk factors, and the recently ongoing stroke epidemiological survey in China. Epidemiological studies suggested that stroke incidence increases with age and that the elderly population is expected to increase over time in China. Stroke mortality increased gradually from 1990 to 2000 but declined since the beginning of the 21st century, probably related to better control of vascular risk factors and the advances in acute stroke care. The Chinese lifestyle has changed rapidly during the past 3 decades. Moreover, China is a big country with substantial geographic disparities. The geographical variation and chronological trend of vascular risk factors may determine changes in the prevalence and subtypes of stroke in China. In this review, the current Chinese researches on the critical management of stroke and the potential direction and support of the Chinese government are discussed.

Should we change the target blood pressure in diabetic patients?

Hypertension is a major modifiable risk factor for cardiovascular morbidity and mortality in diabetic patients. Guidelines recommend lowering blood pressure (BP) to less than 130/80 mmHg in diabetic patients. These recommendations are based on several studies in diabetic patients that showed the benefit of intensive BP control. However in all the studies the achieved BP was higher than 130/80 mmHg. Re-evaluation of earlier studies, as well as more recently accumulated data suggest that intensive BP control is associated with a significant reduction in all-cause mortality and stroke rate, but with no benefit for other microvascular or macrovascular (cardiac, renal and retinal) outcomes. Intensive BP control is associated with an increased risk of serious adverse effects, particularly for systolic BPs levels lower than 130 mmHg. When determining the target BP in diabetic patients one should balance the potential cerebrovascular protection against the increased risk of serious side effects, and the absence of benefit for other circulatory system. It seems therefore, that lowering BP to levels close to 130/80 mmHg should be the main goal of treatment in diabetic patients.

Endovascular treatments of atherosclerotic carotid diseases in China

Stroke induces heavy socioeconomic burdens particularly in developing countries. Considering the multisectional discrepancies, strategies of stroke prevention and management adapted for western populations are not always applicable for patients in developing countries. Currently, carotid endarterectomy is the recommended treatment for severe carotid stenosis in the west. Carotid angioplasty and stenting is an alternative treatment only for patients with a high surgery risk. However, in developing countries such as China, where carotid endarterectomy is widely unavailable, Carotid angioplasty and stenting has developed rapidly in recent years and is becoming a choice of treatment for occlusive carotid diseases.

Vital and functional outcomes of the first-ever hemispheric stroke, epidemiological comparative study between Kunming (China) and Limoges (France)

BACKGROUND

Clinical outcomes and socioeconomic consequences after a stroke may differ between regions.

METHODS

One cohort was established prospectively in Kunming (China) to compare with a cohort of 156 stroke patients included in Limoges (France). During 1 year, patients hospitalized within 48 hours for a first-ever hemispheric stroke were included. Demographic data and neurocardiovascular risk factors were registered. Hemiplegia was evaluated. Functional outcome was assessed using the Barthel Index (BI) after 3 months.

RESULTS

One hundred and eighteen patients were included in Kunming. Patients of Kunming were younger (61.4 ± 13.4 vs 72.3 ± 14.6 years in Limoges, P<0.0001), more involved in professional activity (36.4% vs 12.8%, P<0.0001). Survival analysis indicated that mortality did not differ between cohorts, but independently predicted by coma at the 2nd day (HR=9.33, 95% CI [4.39, 19.78]) and age>70 years (HR=6.29, 95% CI [2.36, 16.59]). Despite a better baseline BI for patients of Kunming (50.0 ± 34.9 vs 37.4 ± 34.2, P=0.0031), after adjustment for confusing, patients in Limoges had a 2.11 OR 95% CI [1.03, 4.31]) to reach a BI>80 at 3 months.

CONCLUSIONS

Functional recovery for patients of Kunming was not as good as expected. The socioeconomic consequences of stroke in Kunming are significant as they involved younger subjects who were still in work.

Stem cells in the treatment of stroke

Stroke is an often devastating insult resulting in neurological deficit lasting greater than 24 hours. In the United States, stroke is the third leading cause of death. In those who do not succumb, any outcome from total recovery over a period of weeks to months to persistent profound neurological deficits is possible. Present treatment centers on the decision to administer tissue plasminogen activator, subsequent medical stabilization and early intervention with rehabilitation and risk factor management. The advent of stem cell therapy presents an exciting new frontier for research in stroke treatment, with the potential to cause a paradigm shift from symptomatic control and secondary prevention to reconstitution of neural networks and prevention of neuronal cell death after neurologic injury.

Stroke in China

1. Following rapid economic development in China, the epidemiological characteristics, management and prevention strategies for stroke are changing. In the present article, we review recent epidemiological data, as well as studies into the management and prevention of stroke in China. 2. The main findings of the studies reviewed suggest that stroke mortality in China has been reduced significantly. The percentage of haemorrhagic strokes in China is significantly higher than that reported in Western countries. The incidence and subtype of stroke varied widely in different regions in China. Some of the modifiable risk factors for stroke are on the increase in China, including hypertension. 3. Management of stroke is slowly being developed and standardized, as evidenced by the establishment of stroke units and improvements in emergency care. Studies on primary and secondary stroke prevention remain insufficient. Well-designed epidemiological surveys and clinical trials for stroke prevention and management are urgently needed in China.

Stroke care development in Mainland China: past, present and future

Stroke care in China was less developed than in western countries but great headway has been made in recent years through unremitting efforts by a group of local neurologists working in this field.

Stratified age-period-cohort analysis of stroke mortality in Japan, 1960 to 2000

BACKGROUND

Although stroke mortality has been decreasing in Japan, in 2000 it was still the third leading cause of death among Japanese of either sex. Elucidation of stroke mortality trends among age, calendar year, and birth cohorts should improve stroke prevention efforts. The objective of this study was to clarify the age, period, and cohort effects on stroke mortality in Japan from 1960 to 2000 by using stratified age-period-cohort models with improved goodness of fit.

METHODS

Death and population from the Vital Statistics of Japan and the National Statistics Bureau, respectively, were tabulated among 12 age groups (30-34, 35-39, 40-44, 45-49, 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84, and 85-89) and 9 quinquennials (1960, 1965, 1970, 1975, 1980, 1985, 1990, 1995, and 2000), which yielded 20 birth cohorts (midyears of 1873, 1878, 1883, 1888, 1893, 1898, 1903, 1908, 1913, 1918, 1923, 1928, 1933, 1938, 1943, 1948, 1953, 1958, 1963, and 1968). A stratified model (age-periods-cohort model) with 7 age classes (30-44, 45-54, 55-64, 65-69, 70-74, 75-79, and 80-89 years) was applied under the assumption that the number of deaths has an extra-Poisson variation.

RESULTS

The stratified model showed that: (1) middle-aged groups (40-64 years in men and 40-59 years in women) had higher mortality than their linear age trends; (2) young (30-44 years) and middle-aged (45-64 years) groups showed different patterns than those of the elderly (65-89 years) age groups: the two younger groups had higher nonlinear period effects than their linear trends between 1970 and 1990, and the trend of decreasing began later (in 1975 in men and 1980 in women, respectively) than it did for the elderly (1970); and (3) the nonlinear cohort effects indicated 4 patterns in each sex, and the effects increased in post-1948 cohort in men and in post-1958 cohort in women.

CONCLUSION

Young and middle age (30-59 years) boosted the mortality, suggesting that this age range should be targeted for increased stroke prevention efforts.

Change in Stroke Incidence from a Population-Based Intervention Trial in Three Urban Communities in China

Stroke has been the main cause of death in most urban residents in China since the 1990s. A community-based intervention trial carried out in China aimed to reduce the incidence and mortality of stroke. In 1991, two well-matched communities each with approximately 50,000 people were selected as intervention or control communities in the urban areas of Beijing, Shanghai and Changsha. Regular health education and health promotion activities were carried out between 1991 and 2000 in the intervention communities but no special action was taken in the control communities. Both fatal and nonfatal stroke cases were meticulously registered during the study in the two communities to assess the effect of long-term intervention. The trend in stroke incidence and the effect of intervention on stroke incidence were analyzed using a Poisson regression model adjusted for age, sex, year and city. Between 1991 and 2000, 2,273 first-ever stroke cases were registered in the intervention communities and 3,015 in the control communities. Geographic variation and changes in the incidence of stroke and its subtypes were found among these 3 cities. Through 10 years of intervention, incidence risks of all, ischemic and hemorrhagic strokes decreased by 11.4% (relative risk 0.8959; 95% confidence interval, CI, 0.8483-0.9460; p < 0.0001), 13.2% (relative risk 0.8676; 95% CI 0.8054-0.9345; p = 0.0002) and 7.2% (relative risk 0.9283; 95% CI 0.8517-1.0117; p = 0.0899), respectively, in the intervention compared with control communities. Accordingly, comprehensive community-based intervention measures could effectively reduce the incidence of stroke in the population.

Stroke in China: epidemiology, prevention, and management strategies

In this review, we examine the current status of stroke epidemiology, prevention, and management strategies in mainland China. The main findings suggested that total age-adjusted incidence of first-ever stroke in China is not very different from that in developed countries. Stroke incidence, mortality, and prevalence varied widely among different regions within China, with a noticeable north-south gradient. The proportion of intracerebral haemorrhage was high and reached 55% in one city. Hypertension is the most important risk factor for stroke. The mass approach combined with a high-risk approach for stroke prevention showed encouraging effects, and various unconventional local therapeutic traditions are commonly used to treat stroke in China. Several national guidelines on stroke prevention and treatment have been developed. Because of methodological limitations in the epidemiology studies, data are unreliable in terms of making any firm conclusions. Up-to-date, well-designed, and well-done epidemiological studies and therapeutic trials in China are urgently needed.

Is the dementia rate increasing in Beijing? Prevalence and incidence of dementia 10 years later in an urban elderly population

OBJECTIVE

To examine the time trend of dementia morbidity over the past decade in Beijing, China.

METHOD

In 1997, 1593 community-dwelling elderly aged 60+ years were examined and followed-up over 2-years to identify incident dementia. A similar cohort study of dementia conducted in the same district 10 years prior was used as historical comparison to examine the time trend of dementia incidence.

RESULTS

Forty prevalent dementia cases were identified at the initial examination for a prevalence of 2.51% (95% CI: 1.74-3.28) and 25 incident cases were identified at the follow-up visit for an incidence of 0.90% (0.55-1.25) among residents aged 60+ years. Alzheimer's dementia (AD) was the most common type of dementia in both prevalent and incident cases.

CONCLUSION

The prevalence and incidence rates of dementia in Beijing were slightly higher than those 10 years ago, which was partly because of population aging. AD became the most common subtype of dementia.

Pharmacologic management of ischemic stroke: relevance to stem cell therapy

Pharmacologic management of the acute phase of the ischemic stroke includes treating the physical and medical conditions that can worsen cerebral injury; administering intravenous thrombolytic therapy (recombinant tissue plasminogen activator) in those who meet current guidelines; instituting prophylactic measures to prevent medical complications; and initiating passive rehabilitation measures. New approaches under investigation include intra-arterial thrombolytic therapy; endovascular embolectomy and clot disruption; and neuroprotective treatments to preserve surviving ischemic tissue. One neuroprotective agent given within 6 h after stroke onset, NXY059, recently met the primary outcome measure in a phase III clinical trial. Pharmacologic management of the subacute and chronic phases involves treatment of risk factors for recurrent stroke and other forms of cardiovascular disease, including hypercholesterolemia, hypertension, and diabetes mellitus. In this phase, antiplatelet therapy can be initiated or continued; smoking, obesity and alcohol intake can be managed; and active rehabilitation can begin through physical, occupational, and speech therapy. A few medications to augment rehabilitation have shown promising results in small clinical trials, but none have been tested in large phase III trials or approved by the US or European regulatory agencies. Thus, there are no pharmacologic measures available to enhance central nervous system restorative processes after acute stroke, and implantation of stem cells provides one promising approach, not only for cell replacement but also for the provision of therapeutic molecules.

Time course and outcome of recovery from stroke: relevance to stem cell treatment

Stroke is the third leading cause of death in the United States after heart disease and cancer; it has an incidence of approximately 750,000 cases per year, and it is a leading cause of disability in adults. The factors predicting a poor outcome from stroke include severe initial neurological dysfunction, hypertension, cardiac arrhythmias, myocardial infarction, hypercholesterolemia, and diabetes mellitus. The armamentarium available for improvement of neurological function after stroke is currently limited to placement in specialized stroke units, optimal therapy for medical complications, and intense physical, occupational and speech rehabilitation. Despite many trials, no pharmacological intervention has been shown convincingly to improve neurological outcome. This review was undertaken to determine the appropriate time for new approaches to the therapy of stroke such as the infusion of stem cells into the central nervous system. The literature shows in large case series that functional recovery from stroke reaches a maximum level by 3-6 months after onset, and no further recovery occurs beyond this time. Nevertheless, about 80% of these patients reach their maximum function for activities of daily living within 6 weeks from onset. Initiation of a clinical trial of stem cell therapy would require demonstration of optimal clinical improvement by neurological evaluations, with no change over at least 4 weeks of observation. Accordingly, in subjects with first-ever ischemic stroke who remained neurologically unchanged from the second until the third month after the acute event, implementation of stem cell therapy would be appropriate at approximately 3 months after the stroke.

Regional variation in hospitalization for stroke among Asians/Pacific Islanders in the United States: a nationwide retrospective cohort study

Background

In Asia, stroke incidence varies dramatically from country to country. Little is known about stroke incidence in Asians/Pacific Islanders in the US, where regional heterogeneity in Asian/Pacific Islander sub-populations is great. We sought to characterize both the national and regional incidences of first and recurrent hospitalized acute ischemic stroke, subarachnoid hemorrhage, and intracerebral hemorrhage in Asians/Pacific Islanders compared to non-Hispanic whites.

Methods

We used the National Inpatient Sample of the 1997 Healthcare Cost and Utilization Project. It is a 20% stratified sample of hospitalizations to nonfederal hospitals in the US. National and regional projections were made using sampling weights specific for patients and hospitals. We identified stroke subtypes using previously validated ICD-9 codes. Age-adjusted incidence rates were calculated using the direct method with the US population in 2000 as the standard.

Results

There were 169,386 stroke hospitalizations in the database. Nationally, compared to whites, Asians/Pacific Islanders were more likely to have subarachnoid hemorrhage (incidence rate ratio {RR} female: 1.53, 95% CI 1.41–1.65; male RR: 1.13, 95% CI 1.00–1.27) and intracerebral hemorrhage (female RR 1.29, 95% CI 1.22–1.36; male RR: 1.58, 95% CI 1.50–1.67). However, when examined by geographic regions, Asians/Pacific Islanders had higher incidence rates of subarachnoid hemorrhage and intracerebral hemorrhage predominantly in the West, and lower rates of stroke elsewhere.

Conclusion

Stroke incidence varies 3-fold among Asians/Pacific Islanders residing in different US regions. Geographic variation is less dramatic in whites. Whether genetic or cultural differences are responsible for dramatic heterogeneity among Asian/Pacific Islander populations is unclear and deserves further study.

Protein, body weight, and cardiovascular health

Widespread popularity of high-protein diets has drawn controversy as well as scientific interest. By reducing intake of carbohydrates and increasing consumption of fats and proteins, such diets are thought to increase satiety, facilitate weight loss, and improve cardiovascular risk factors. In recent years, many randomized controlled studies have compared the effects of higher-protein diets on weight loss and cardiovascular risk factors with those of lower-protein diets. The aim of this review was to provide an overview of experimental and epidemiologic evidence regarding the role of protein in weight loss and cardiovascular risk. Emerging evidence from clinical trials indicates that higher-protein diets increase short-term weight loss and improve blood lipids, but long-term data are lacking. Findings from epidemiologic studies show a significant relationship between increased protein intake and lower risk of hypertension and coronary heart disease. However, different sources of protein appear to have different effects on cardiovascular disease. Although optimal amounts and sources of protein cannot be determined at this time, evidence suggests a potential benefit of partially replace refined carbohydrates with protein sources low in saturated fats.

Prevalence of and Factors Associated with Poststroke Depression: A Malaysian Study

This study investigated the prevalence of depression 3-6 months poststroke and examined specific factors associated with depression in a stroke population of the University Malaya Medical Centre, Kuala Lumpur, Malaysia. It was hypothesised that poststroke depression (PSD) is prevalent in the poststroke population of University Hospital Malaysia and that PSD is significantly correlated with demographics, educational background, medical history, rehabilitation attendance, traditional medicine use, prestroke and poststroke activities, religiousness, activities of daily living, and social support. The study group comprised 80 patients admitted to the hospital with stroke of any etiology. Mean patient age was 56.8 years (standard deviation +/- 12.5 years). The results were derived by comparing the 80 stroke patients with 80 controls matched for age, sex, race, and medication use. Results were also derived from comparisons between depressed and nondepressed members of the stroke population (n = 80). The diagnosis of depression was based on the Zung Self-Rating Scale and confirmed by a psychiatrist, based on DSM-IV criteria. Interviews were conducted based on a 26-item questionnaire, modified Barthel Index, and Social Resources Scale were used to assess which factors correlated with depression. Depression was found to be common among Malaysians 3-6 months after stroke. A total of 66% of the patients were depressed, with depression considered mild in 51% and moderate to severe in 15%. It was demonstrated that the occurrence of depression was significantly correlated with age, ethnicity, noncontinuance of prestroke lifestyles, and poor performance in the activities of daily living rating.

Does Danshen improve disability after acute ischaemic stroke?

OBJECTIVES

Danshen, a Chinese herb, has been used as a standard treatment for acute ischaemic stroke in China. This study assesses the quality of all randomized control trials (RCTs) comparing Danshen of any preparation to without Danshen (placebo or other western or herbal medicines), and to evaluate its effectiveness in improving disability.

MATERIALS AND METHODS

Systematic review through literature search in MEDLINE, Cochrane Library, China Biological Medicine Database and others. The main outcome measure is disability improvement on the Chinese National Disability Scale (CNDS) at 2 weeks after intervention.

RESULTS

Of 33 Danshen control trials for acute ischaemic stroke identified in the literature, none were placebo-controlled. Eleven RCTs comparing Danshen with one of seven Western and two herbal medicines met the inclusion criteria for review, however, these studies were of poor quality. Compared with the nine medicines, the effect of Danshen was inferior in five trials and not significantly different in another six trials. For the two trials comparing Danshen with Buflomedil, the combined odds ratio (OR) was 0.27 (95% CI: 0.12-0.61) favouring Buflomedil, but the test of homogeneity revealed heterogeneity (P = 0.083). For the two trials comparing Danshen with Naloxone, the combined OR was 0.16 (95% CI: 0.07-0.40) favouring Naloxone. However, none of the nine medicines per se has been proven effective in post-stroke disability improvement.

CONCLUSIONS

The existing Danshen RCTs are not placebo-controlled and are of poor quality, therefore, there is no substantial evidence that Danshen is effective. Systematic review on RCTs comparing Danshen with other medicines does not support the notion that Danshen may be beneficial to disability improvement after acute ischaemic stroke.

Geographical, seasonal and gender differences in folate status among Chinese adults

Low blood folate concentrations have been associated with cardiovascular disease, neural tube defects and selected cancers, but little is known about folate status in Chinese adults. In a cross-sectional study we measured the plasma and red blood cell folate concentrations in 2422 Chinese men and women aged 35 to 64 y, living in the North and South of China, who provided blood samples either in March or September of 2001. The geometric mean concentrations of plasma and red blood cell folate were lower among Northerners than Southerners (adjusted geometric means, 8.4 and 502, and 16.7 and 811 nmol/L, respectively) controlling for age, gender, season (spring and fall), area (urban and rural), BMI, multivitamin use, alcohol intake and current smoking status. We estimated that approximately 40% of the Northerners and approximately 6% of the Southerners had plasma folate concentrations lower than the 6.8 nmol/L (3 microg/L), and approximately 30% of the Northerners and approximately 4% of the Southerners had red blood cell folate concentrations lower than the 363 nmol/L (160 microg/L), levels used to define folate deficiency. Within each region, men had lower plasma folate concentrations than women (6.9 versus 9.8 nmol/L in the North, and 14.5 versus 19.6 nmol/L in the South). In men, current smokers had a higher risk of folate deficiency compared with nonsmokers [adjusted odds ratios, 1.9 (95% CI, 1.4-2.6) for plasma folate deficiency and 2.5 (95% CI, 1.7-3.6) for red blood cell folate deficiency (P < 0.001)]. Our findings suggest that a large proportion of Chinese adults have a low folate status, especially those living in northern China where 60% of the men are plasma folate deficient in the spring. Further studies are needed to elucidate the factors that influence folate concentrations among middle-aged Chinese and to evaluate possible intervention strategies.

A study on additional early physiotherapy after stroke and factors affecting functional recovery

OBJECTIVE

To investigate whether additional early physiotherapy after stroke improved functional recovery in stroke patients.

DESIGN

A prospective, randomized, controlled study.

SETTING

One stroke ward and an acute stroke unit in a large teaching hospital, southern China.

SUBJECTS

Patients with first-onset stroke consecutively admitted to the stroke centre.

INTERVENTIONS

One group (n = 78) received additional early physiotherapy (AEP) for 45 minutes, five days a week for four weeks starting within the first week since stroke onset; the routine therapy (RT) group (n = 78) received no professional rehabilitation therapy.

MAIN OUTCOME MEASURES

Glasgow Coma Scale, Mini-Mental State Examination, Fugl-Meyer Assessment of Motor Recovery, Clinical Neurological Deficit Scale and Modified Barthel Index (MBI).

RESULTS

Patients from the AEP group had a high drop-out rate (n = 28), but those remaining made relatively better functional recovery at 30 days than those from the RT group if measured by MBI. Multiple linear regression analysis revealed that cognitive disturbance, aphasia, double incontinence, site of lesion and sensory impairment might affect functional recovery after stroke.

CONCLUSIONS

Additional early physiotherapy might improve independence of patients after stroke but failed to show benefit in other aspects in our study. Cognitive disturbance, aphasia, double incontinence, site of lesion as well as sensory impairment might affect functional outcome after stroke.

Dementia research in China

There is little information on dementia research in China in the international literature. This paper is an overview of studies on dementia conducted in China. Studies on dementia research in China were identified through a literature search, as well as through consulting Chinese psychiatrists and neurologists with expertise in the field. These studies were then reviewed. Epidemiological studies on dementia in China find the rates of dementia at the lower end of rates in Caucasians. There seems to be regional variation in the ratio of vascular dementia to Alzheimer's disease in China. In addition to epidemiological studies, there are studies on the genetics, psychopathology, neurophysiology and drug treatment in dementia. There is much research activity in China in the field of dementia and further cross-cultural studies are useful to examine the cultural differences in various areas of dementia research.

Gender differences and the effects of synthetic exogenous and non-synthetic estrogens in focal cerebral ischemia

The role of gender difference and estrogen in ischemic cerebrovascular events is controversial. Evidence is lacking as to whether or not there are significant gender differences in the incidence and outcome of stroke in the clinical setting. Recent clinical epidemiological studies have demonstrated that there is no significant association between the use of hormonal replacement therapy and the risk of stroke. However, several animal studies have shown that there are gender differences in stroke outcome and that exogenous administered estrogens are neuroprotective. In this study, the influence of gender differences and the effects of synthetic and non-synthetic estrogens were examined in a model of focal cerebral ischemia using 210 male, intact female, and ovariectomized female rats. All animals underwent 3 h of middle cerebral artery and bilateral common carotid artery occlusion. After 72 h, the rats were sacrificed and stained for histological assessment of infarction. There were no gender differences in infarction volume. Intravenous administration of either low or high dose 17 beta-estradiol or tibolone did not alter infarct volume. Subcutaneous administration of low and high dose 17beta-estradiol using 7-day release pellets did not alter infarct volume. Low dose tibolone using implanted 7-day release pellets did not alter infarct volume. However, high dose tibolone using implanted 7-day release pellets significantly (P<0.05) reduced infarct volume only in ovariectomized female rats. These results demonstrate that estrogen therapy has no effect on infarction volume following severe focal cerebral ischemia.

A systematic review of randomized evidence for fibrinogen-depleting agents in acute ischemic stroke

OBJECTIVE

To assess the efficacy and safety of fibrinogen-depleting agents (snake venom extracts) in the treatment of acute ischemic stroke.

METHODS

A systematic review of all the relevant randomized controlled trials (RCTs) was performed. RCTs were identified from the Cochrane Stroke Group's Specialized Trial Register, additional electronic and hand searching, and personal contact with pharmaceutical companies. We included all completed and unconfounded truly or quasi-randomized trials in patients with ischemic stroke comparing fibrinogen depleting agents with control started within 14 days of the stroke onset. The Peto method was used for analysis.

RESULTS

Eight completed and two ongoing RCTs have been identified so far. Only three trials using ancrod (182 patients) met the inclusion criteria. Ancrod was associated with a significant reduction in early deaths (5.6% v 16%; odds ratio [OR], 0.33; 95% confidence interval [CI], 0.13 to 0.85; 2P=.02) suggesting that treatment of 100 patients would avoid about 10 early deaths. The frequency of asymptomatic intracranial hemorrhage shown by computed tomography was similar between ancrod-treated and control groups (7.6% v 9.6%; OR, 0.78; 95% CI, 0.26 to 2.33; 2P=.65). No major intracranial or extracranial hemorrhages or recurrent ischemic strokes occurred in the ancrod-allocated patients. There were nonsignificant trends in favor of ancrod in death from any cause (OR, 0.57; 95% CI, 0.27 to 1.23; 2P=.15) and death or disability (OR, 0.52; 95% CI, 0.26 to 1.03; 2P=.06) at the end of trial follow-up.

CONCLUSIONS

There were too few patients and outcome events to draw reliable conclusions from the present data. Although ancrod-like agents appeared promising, their routine use cannot be recommended at the moment. Two ongoing trials (including about 1,000 patients in total) will provide more data. Future trials should test simpler fixed-dose regimens to allow better generalizability.

Ischemic strokes in children

Ischemic stroke is an uncommon, but significant cause of disability in childhood. Children with strokes present with predictable deficits as adults do; however, fever and seizures at stroke onset are more common in children than in adults. Strokes in children have diverse etiologies and require extensive evaluation. Etiology remains obscure in up to half of the patients. Prognosis in childhood stroke is not benign and up to 50% of pediatric stroke patients have chronic sequelae. Emerging therapies may alter prognosis in certain populations of children at risk for stroke, but more research is necessary.

A novel type of pyridine nucleotide-disulfide oxidoreductase is essential for NAD+- and NADPH-dependent degradation of epoxyalkanes by Xanthobacter strain Py2

Epoxide degradation in cell extracts of Xanthobacter strain Py2 has been reported to be dependent on NAD+ and dithiols. This multicomponent system has now been fractionated. A key protein encoded by a DNA fragment complementing a Xanthobacter strain Py2 mutant unable to degrade epoxides was purified and analyzed. This NADP-dependent protein, a novel type of pyridine nucleotide-disulfide oxidoreductase, is essential for epoxide degradation. NADPH, acting as the physiological cofactor, replaced the dithiols in epoxide conversion.