Shengping Wu

Prevalence, Incidence, and Mortality of Stroke in China: Results from a Nationwide Population-Based Survey of 480 687 Adults.

Background: China bears the biggest stroke burden in the world. However, little is known about the current prevalence, incidence, and mortality of stroke at the national level, and the trend in the past 30 years. Methods: In 2013, a nationally representative door-to-door survey was conducted in 155 urban and rural centers in 31 provinces in China, totaling 480 687 adults aged ≥20 years. All stroke survivors were considered as prevalent stroke cases at the prevalent time (August 31, 2013). First-ever strokes that occurred during 1 year preceding the survey point-prevalent time were considered as incident cases. According to computed tomography/MRI/autopsy findings, strokes were categorized into ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and stroke of undetermined type. Results: Of 480 687 participants, 7672 were diagnosed with a prevalent stroke (1596.0/100 000 people) and 1643 with incident strokes (345.1/100 000 person-years). The age-standardized prevalence, incidence, and mortality rates were 1114.8/100 000 people, 246.8 and 114.8/100 000 person-years, respectively. Pathological type of stroke was documented by computed tomography/MRI brain scanning in 90% of prevalent and 83% of incident stroke cases. Among incident and prevalent strokes, ischemic stroke constituted 69.6% and 77.8%, intracerebral hemorrhage 23.8% and 15.8%, subarachnoid hemorrhage 4.4% and 4.4%, and undetermined type 2.1% and 2.0%, respectively. Age-specific stroke prevalence in men aged ≥40 years was significantly greater than the prevalence in women (P<0.001). The most prevalent risk factors among stroke survivors were hypertension (88%), smoking (48%), and alcohol use (44%). Stroke prevalence estimates in 2013 were statistically greater than those reported in China 3 decades ago, especially among rural residents (P=0.017). The highest annual incidence and mortality of stroke was in Northeast (365 and 159/100 000 person-years), then Central areas (326 and 154/100 000 person-years), and the lowest incidence was in Southwest China (154/100 000 person-years), and the lowest mortality was in South China (65/100 000 person-years) (P<0.002). Conclusions: Stroke burden in China has increased over the past 30 years, and remains particularly high in rural areas. There is a north-to-south gradient in stroke in China, with the greatest stroke burden observed in the northern and central regions.

Prevalence of Alzheimer’s Disease and Other Dementing Disorders in an Urban Community of Beijing, China

A door-to-door two-phase study was used to investigate the prevalence of senile dementia in an urban community of Beijing. In the study population, 5,003 individuals aged 60 years and older (≥65 years, n = 3,728) were screened at home with the Chinese version of the MMSE. Persons who screened positive for dementia, using different cutoff scores based on degree of literacy, were further evaluated using the criteria of DSM-III-R and ICD-10. Among subjects who screened positive in phase I, 134 were diagnosed as having dementia in phase II. The prevalence ratios of dementia were 2.68% in the population aged 60 years and older, and 3.49% in the population aged 65 years and older. The prevalence rates among those aged 65 years and older were 1.85% for Alzheimer’s disease, 1.37% for vascular dementia and 0.27% for other dementia (including mixed dementia). The prevalence of all dementia and AD increased steeply with advancing age and was consistently higher in women, but it was not obviously higher for VaD in women. Alzheimer’s disease was the commonest type of dementia. Our prevalence figures for dementia and AD are similar to those previously reported for China.

Body mass index and risk of total and type-specific stroke in Chinese adults: results from a longitudinal study in China

Background The prevalence rate of overweight and obese has been escalating over the past two decades in China. Even so, the association between obesity and stroke still remains unclear to some extent. Aims The aim of this study was to elucidate the association between body mass index and stroke in a large Chinese population cohort. Methods A cohort of 26 607 Chinese people, aged over 35 years, was investigated in 1987. Baseline information of body weight and height was used to calculate BMI (weight in kilograms divided by height in meters squared, kg/m2). Cox proportional hazards model was fitted to estimate hazard ratios of stroke adjusted for age, educational level, smoking and alcohol consumption. Results The 11-year follow-up revealed (241 149 person-years) a total of 1108 stroke events (614 ischemic, 451 hemorrhagic, and 44 undefined stroke). Body mass index ≥ 30·0 was an independent risk factor for stroke both in men and women. Compared with normal weight, hazard ratios for total stroke were 0·74 in men underweight (95% confidence interval: 0·53∼1·03), 1·63 overweight (95% confidence interval: 1·35∼1·96), and 2·20 with obesity (95% confidence interval: 1·47∼3·30); and with ischemic stroke, hazard ratios were 0·52 in those underweight (95% confidence interval: 0·30∼0·89), 208 overweight (95% confidence interval: 1·65∼2·62), and 3·80 with obesity (95% confidence interval: 2·47∼5·86). In women, the corresponding hazard ratios for total stroke were 0·79 underweight (95% confidence interval: 0·58∼1·07), 1·42 overweight (95% confidence interval: 1·16∼1·73), and 1·57 with obesity (95% confidence interval: 1·06∼2·31); and for those with ischemic stroke, 0·92 underweight (95% confidence interval: 0·59∼1·43), 1·90 overweight (95% confidence interval: 1·44∼2·50), and 2·42 with obesity (95% confidence interval: 1·50∼3·93). There appeared an evident dose-response relationship between body mass index and the risk of developing stroke, which still appeared, however, adjusted low for hypertension, diabetes, and heart disease. Decreased risk for stroke in the leanest group was confined to men only. No association was found between body mass index and hemorrhagic stroke in both genders. Conclusions Our data suggest that body mass index was an independent risk factor for total and ischemic stroke but not for hemorrhagic stroke in both genders. Association between body mass index and stroke was extremely mediated by hypertension, diabetes, and heart disease. Decreased risk for the leanest group was confined to men.

Longitudinal Study of Blood Pressure and Stroke in over 37,000 People in China

As part of a longitudinal study performed in urban China, 37,655 subjects were evaluated for stroke risk factors, including having their blood pressure measured in a standard fashion. The cohort was followed for 3.5 years during which time 427 subjects experienced incident strokes – 221 ischemic, 203 hemorrhagic, and 3 undefined. Both systolic and diastolic blood pressure were significantly related to risk of stroke and stroke type. Associations were stronger for systolic than diastolic blood pressure. These results emphasize the importance of systolic blood pressure, as opposed to diastolic, as a risk factor for stroke. In this study, the risk of stroke is increased by about 25% with each 10 mm Hg increase in systolic blood pressure.

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.

Hypertension Detection, Management, Control and Associated Factors Among Residents Accessing Community Health Services In Beijing

The aim of this study was to analyse high blood pressure detection, management, control and associated factors among residents accessing community health services (CHSs) in Beijing. We screened for HBP in 9524 individuals aged 50 years or older who accessed care in four Beijing CHSs. Among the 9397 residents with questionnaire responses that qualified them for inclusion in the study, 5029 patients with HBP were identified, 1510 (i.e., 30% of the HBP patient group) of whom were newly identified cases. The rate of hypertension detection was 53.5%. Among the 5029 HBP patients, the rates of awareness, treatment and control of hypertension were 70.0%, 62.1% and 29.6%, respectively. In general, the rate of hypertension control was higher when the rates of hypertension awareness and treatment were higher in subgroups stratified by different sociodemographic and risk factors, except for the overweight and obesity subgroups. In conclusion, suboptimal HBP awareness, treatment, and control are still major problems confronting CHSs in Beijing. Control of hypertension in the population may be improved by increasing awareness and improving the treatment of hypertension in CHSs.

Public knowledge of stroke in Chinese urban residents: a community questionnaire study.

Abstract Background and purpose: Intensive control of the risk factors of stroke and the pre-hospital delay after stroke onset both depend on the level of knowledge of stroke in the general population. Our primary objective was to assess the public knowledge about stroke among urban residents in four cities in China. Methods: A semi-structured interview and questionnaire was delivered in a survey. Standardized risk factor and symptom statements were used to measure knowledge. The setting of two communities from four different cities of China was used to target a mix of social class and geography. Using systematic sampling and the household as a unit, at least 300 households were chosen in one community. Each household selected one person to fill in the self-designed questionnaire. Uniform training of community physicians was conducted before the survey, and the community physicians completed the survey by face to face indoor-investigation. Results: Total integral questionnaires numbered 2519. The investigation showed that (1) hypertension was identified as a risk factor by nearly 90% of residents. Dyslipidemia, smoking, diabetes, and non-modifiable risk factors were identified by less than 65%; (2) medical therapy of hypertension and diabetes was known by nearly 80% of residents, and the awareness of lifestyle modification was less; (3) weakness or numbness were the most common symptoms identified by community residents (80·2%), and the awareness of other symptoms of stroke ranged from 58·2 to 71·2%; (4) the stroke knowledge score and education level were positively correlated (r s = 0·088, P<0·001), and age was negatively correlated (r s = −0·142, P<0·001); (5) 53·0% of residents would call an emergency medical system once stroke symptoms began; (6) the main sources of information about stroke were television (74·4%), doctors (63·2%) and newspapers (61·8%). Conclusion: At present, the urban community residents in China are lacking in knowledge about stroke. Going forward, we should strengthen health education through television, medical staff, newspapers, magazines. Targeted educational populations should be directed at those who are elderly, lower education, male and high risk.

Prevalence, Incidence, Prognosis, Early Stroke Risk, and Stroke-Related Prognostic Factors of Definite or Probable Transient Ischemic Attacks in China, 2013

The epidemiological characteristics of transient ischemic attacks (TIAs) in China are unclear. In 2013, we conducted a nationally representative, door-to-door epidemiological survey on TIA in China using a complex, multistage, probability sampling design. Results showed that the weighted prevalence of TIA in China was 103.3 [95% confidence interval (CI): 83.9–127.2] per 100,000 in the population, 92.4 (75.0–113.8) per 100,000 among men, and 114.7 (87.2–151.0) per 100,000 among women. The weighted incidence of TIA was 23.9 (17.8–32.0) per 100,000 in the population, 21.3 (14.3–31.5) per 100,000 among men, and 26.6 (17.0–41.7) per 100,000 among women. No difference in average prognosis was found between TIA and stroke in the population. Weighted risk of stroke among TIA patients was 9.7% (6.5–14.3%), 11.1% (7.5–16.1%), and 12.3% (8.4–17.7%) at 2, 30, and 90 days, respectively. The risk of stroke was higher among male patients with a history of TIA than among female patients with a history of TIA (OR: 2.469; 95% CI: 1.172–5.201; P = 0.018), and higher among TIA patients with hypertension than among TIA patients without hypertension (OR: 2.671; 1.547–4.613; P < 0.001). It can be concluded that there are an estimated 1.35 million TIA patients nationwide, with 0.31 million new cases of TIA annually in China. TIA patients were not better managed prior to a stroke event. Early risk of stroke among TIA patients is high. Sex and hypertension may be stroke-associated prognostic factors among TIA patients. TIA clinics and surveillance should be integrated into the national health-care system.