Greenspace exposure and poststroke disability: A nationwide longitudinal study.

INTRODUCTION: Exposure to greenspace has been reported to reduce stroke mortality, but there is a lack of evidence regarding poststroke disability. This study aimed to investigate the association between long-term greenspace exposure and the risk of poststroke disability. METHODS: Based on the China National Stroke Screening Survey from 2013 to 2019, a total of 65,892 visits from 28,085 stroke survivors with ≥ 2 visits were included in this longitudinal study. Long-term greenspace exposure was assessed by a 3-year average of the Normalized Difference Vegetation Index (NDVI) and the proportion of green land cover according to participants' residential communities. Poststroke functional status was assessed with the modified Ranking Score (mRS) at each visit; a cutoff score > 2 indicated disability. Fixed effects regressions were used to examine the association of greenspace exposure with continuous mRS scores or binary indicators for disability. RESULTS: The annual mean NDVI value was 0.369 (standard deviation = 0.120) for all visits among stroke survivors. With full adjustments, each 0.05 increase in NDVI was associated with a 0.056-unit (95 % confidence interval (CI): 0.034, 0.079) decrease in the mRS score and a 46.6 % (95 % CI: 10.0 %, 68.3 %) lower risk of poststroke disability. An L-shaped curve was observed for the nonlinear associations between NDVI and mRS score or disability. Additionally, each 1 % increase in grasslands, savannas, forest, and croplands was associated with 0.008- (95 % CI: 0.002, 0.014), 0.003- (95 % CI: 0.001, 0.005), 0.001- (95 % CI: -0.015, 0.018), and 0.002-unit (95 % CI: -0.003, 0.007) decreases in the mRS score, respectively. CONCLUSIONS: Increasing greenspace was inversely associated with mRS score. Greenspace planning can be a potential intervention to prevent poststroke disability.

Long-Term Exposure to Ozone Increases Neurological Disability after Stroke: Findings from a Nationwide Longitudinal Study in China.

Exposure to ozone (O3) is associated with stroke incidence and mortality. However, whether long-term exposure to O3 is associated with post-stroke neurological disability remains unknown. This study investigated the relationship based on the longitudinal analysis of China National Stroke Screening Survey (CNSSS), which included 65,778 records of stroke patients. All of the analyzed patients were followed-up at least twice. Stroke disability was assessed using the modified Rankin scale (mRS). Long-term exposure was assessed by the peak-season or annual mean of maximum 8-h O3 concentrations for 365 days before the mRS measurement. We used fixed-effect models to evaluate the associations between O3 and mRS score, with adjustment for multiple confounders, and found a 10 µg/m3 increase in peak-season O3 concentration was associated with a 0.0186 (95% confidence interval [CI] 0.0115-0.0256) increment in the mRS score. The association was robust in various subpopulations. For secondary outcomes, for each 10 µg/m3 increment in peak-season O3, the odds ratio of an increased mRS score (vs. unchanged or decreased mRS score) increased by 23% (95% CI 9-37%). A nonlinear analysis showed a sublinear association between O3 exposure and risk for post-stroke disability. A saturation effect was observed at an O3 concentration of more than ~120 µg/m3. Our study adds to evidence that long-term exposure to O3 increases the risk of neurological disability after stroke.

Metformin use is associated with low risk of case fatality and disability rates in first-ever stroke patients with type 2 diabetes.

Background: To assess the effectiveness of metformin treatment on long-term outcomes in first-ever stroke patients with type 2 diabetes mellitus (T2DM) in China. Methods: From August to September 2019, all patients with first-ever stroke and T2DM from 232 hospitals in China Mainland were included. The enrolled patients were divided into two groups: the metformin treatment (MT) and the no-metformin treatment (No-MT) groups. All discharged patients would receive a telephone follow-up at 12-month after admission. Results: In total, 7587 first-ever stroke patients with T2DM [age: median (IQR) = 66 (57-73) years; 57.35% male] were recruited. Out of those 7587 included patients, 3593 (47.36%) received MT. The in-hospital case fatality rate was lower in the MT group than the No-MT group [MT group versus No-MT group: 1.09% versus 2.30%; absolute difference = -1.75% (95% CI = -2.15 to -1.17%); OR = 0.63 (95% CI = 0.47 to 0.84)]. The 12-month case fatality rate was lower in the MT group than the No-MT group [4.72% versus 8.05%; absolute difference = -4.05% (95% CI = -5.58 to -2.41); OR = 0.69 (95% CI = 0.50 to 0.88)]. The 12-month disability rate was also lower in the MT group than the No-MT group [14.74% versus 19.41%; absolute difference = -5.70% (95% CI = -7.25 to -3.22); OR = 0.83 (95% CI = 0.70 to 0.95)]. Furthermore, the recurrence rate did not differ significantly between the MT and No-MT groups (p = 0.29). Conclusion: The study reveals that metformin use in stroke patients with T2DM results in a less severe stroke and lower fatality and disability rates.

Rates of intravenous thrombolysis and endovascular therapy for acute ischaemic stroke in China between 2019 and 2020.

BACKGROUND: In recent years, a series of initiatives have been launched to promote intravenous thrombolysis (IVT) and endovascular therapy (EVT) for acute ischaemic stroke (AIS) in China. We aimed to update the rates of IVT and EVT in China between 2019 and 2020 and to evaluate the current IVT and EVT according to hospital grades. METHODS: Cross-sectional data on patients receiving IVT/EVT were derived from the Bigdata Observatory platform for Stroke of China (BOSC). The monthly number of discharged patients with a principal diagnosis of AIS was derived from the first pages of medical records of each hospital. The rates and information of IVT and EVT were analysed according to hospital grades. FINDINGS: During this period, 938 tertiary hospitals and 786 secondary hospitals from 31 provinces continuously reported data to the BOSC. The overall IVT rate for AIS was 5·64%, and the EVT rate was 1·45%. The IVT rate in secondary hospitals was higher than that in tertiary hospitals (6·39% vs. 5·39%, P < 0·001), whereas the EVT rate in secondary hospitals was much lower than that in tertiary hospitals (0·29% vs. 1·84%, P < 0·001). Significant differences in demographic and clinical characteristics of patients receiving IVT/EVT were also shown between tertiary and secondary hospitals. INTERPRETATION: The rates of IVT and EVT for AIS have greatly increased in China, but there is still a large gap compared with developed countries. Hospital inhomogeneity in IVT and EVT suggests the importance of developing a region-specific network for stroke treatment. FUNDING: None.

Thrombolytic DNT and fatality and disability rates in acute ischemic stroke: a study from Bigdata Observatory Platform for Stroke of China.

OBJECTIVE: To evaluate whether shorter door-to-needle times (DNT) with intravenous tissue plasminogen activator (tPA) for acute ischemic stroke are associated with improved 1-year outcomes in Chinese patients. METHODS: From August to September 2019, all first-ever ischemic stroke patients who were treated with intravenous tPA within 4.5 h of the time they were last known to be well from 232 hospitals in China were included. Patients were divided into four groups according to DNT time (≤ 45 min; 45-60 min; 60-90 min; > 90 min). All discharged patients would receive a telephone follow-up at 12-month after admission. Death and disability events were recorded. RESULTS: Finally, 2370 patients were analyzed. The median age was 65 years, 66.6% were male, and 2.4% were of ethnic minorities. In the 1-year follow-up, 211 patients died (8.9%; 95%CI: 7.8-10.0%). The patients (53.1%) had DNT times of longer than 45 min, compared with those treated within 45 min, did not have significantly higher 1-year mortality (8.9% vs 8.9% [absolute difference, 0.03% {95% CI, - 0.05% to - 0.10%}, odd ratio {OR}, 1.00 {95% CI, 0.75 to 1.33}]). In addition, 385 patients (16.2%; 14.8-17.3%) out of those survivors had disability events. The patients had DNT times of longer than 45 min, compared with those treated within 45 min, did not have significantly higher 1-year disability rate (18.9% vs 16.7% [absolute difference, 1.9% {95% CI, 1.1% to 3.0%}, odd ratio {OR}, 1.22 {95% CI, 0.89 to 1.43}]). CONCLUSIONS: The results did not show that shorter DNT for tPA administration was significantly associated with better 1-year outcomes.

Impact of a health campaign on Chinese public awareness of stroke: evidence from internet search data.

INTRODUCTION: Health campaigns have the potential to improve public awareness, but their impact can be difficult to assess. Internet search data provide information concerning online health information-seeking behaviour in the population and may serve as a proxy for public awareness to evaluate health campaigns. This study aimed to measure the impact of World Stroke Day (WSD) in China using Baidu search data. METHODS: Daily search index values (SIV) for the term 'stroke' were collected from January 2011 to December 2019 using the Baidu Index platform. We examined the mean difference in SIV between the 4 weeks surrounding WSD (period of interest) and the rest of the year (control period) for each year by t-test analysis. The mean difference between the period of interest and the control period was also calculated. The joinpoint regression model was used to analyse the trends of internet search activity 30 days before and after WSD for each year (2011-2019). Finally, the top and rising queries related to stroke during the week of the campaign in 2020 were summarised. RESULTS: A significant mean increase in SIV of 418.5 (95% CI: 298.8 to 538.2) for the period of interest surrounding WSD was observed, 36.2% greater than the SIV during the control period (2011-2019). Short-term joinpoint analysis showed a significant increase in SIV 3 days before WSD, a peak on WSD and a decrease to the precampaign level 3 days after WSD. The rising related queries suggested that the public had increasing concerns about stroke warning signs, stroke prevention and stroke recovery during the campaign. CONCLUSIONS: The WSD campaign increased internet search activity. These research techniques can be applied to evaluation of other health campaigns. Advancing understanding of public demand will enable tailoring of the campaign and strengthen health management.

Status of hyperhomocysteinemia in China: results from the China Stroke High-risk Population Screening Program, 2018.

A nationwide survey was conducted from October 2018 to September 2019 to assess the prevalence of hyperhomocysteinemia (Hhcy) and its influencing factors in China. A standardized questionnaire was used to collect information. Hhcy was defined as the level of serum homocysteine (HCY) ⩾ 15.0µmol/L. The H-type hypertension (HHYP) was defined as hypertension with an elevated serum HCY 15.0µmol/L). Finally, 110 551 residents ⩾ 40 years of age from 31 provinces in the mainland of China were included. Overall, the median serum HCY level was 10.9µmol/L (interquartile range 7.9-15.1). A total of 28 633 participants (25.9%) were defined as Hhcy. The Hhcy prevalence ranged from 7.9% in Shanghai to 56.8% in Tianjin. The data showed that serum HCY levels were associated with age, male gender, cigarette smoking, hypertension, diabetes, ethnicity, endurance in exercise (inverse), and fruit and vegetable intake (inverse). In addition, 15 486 participants were defined as HHYP, and the rate was 14.0%. HHYP was an independent predictor of stroke with an adjusted odds ratio of 1.752 (95% CI 1.338-2.105). The geographical distribution pattern of the Hhcy epidemic reflects dynamic differences, and national strategies should be carried out to further improve the care of patients with Hhcy across China.

Case-fatality, disability and recurrence rates after first-ever stroke: A study from bigdata observatory platform for stroke of China.

BACKGROUND: There is currently a lack of data on stroke hospitalizations and long-term outcomes in China. Therefore, we investigated 12-month stroke fatality, disability, and recurrence rates after the first-ever stroke. METHODS: This was a prospective nationwide hospital-based cohort study. From August to September 2019, all patients with first-ever stroke (ischemic stroke [IS], intracerebral hemorrhage [ICH], and subarachnoid hemorrhage [SAH]) and with symptom onset within 14 days from 232 hospitals were included. Case fatality, disability, and recurrence rates for one year were estimated. RESULTS: In total, 36250 first-ever stroke patients from 194 hospitals were recruited (median age was 65(IQR, 56-73) years and 61.4 % were male). The rate of intravenous thrombolysis and endovascular treatment for IS were 9.5 % and 4.4 %, respectively. In-hospital death rate was 1.9 % (95 %CI: 1.7 %-2.0 %) for stroke inpatients, ranging from 0.9 % (0.8 %-1.1 %) for IS to 5.1 % (4.6 %-5.6 %) for ICH. The 12-month fatality rate was 8.6 % (95 %CI: 8.3 %-8.9 %) for discharged stroke patients, ranging from 6.0 % (5.7 %-6.3 %) for IS to 17.7 % (16.7 %-18.7 %) for ICH. The 12-month disability rate was 16.6 % (95 %CI: 16.2 %-17.0 %) for stroke survivors, ranging from 11.1 % (9.3 %-12.8 %) for SAH to 29.2 % (27.9 %-30.4 %) for ICH. The stroke recurrence rate was 5.7 % (5.5 %-6.0 %) for stroke survivors, ranging from 2.5 % (1.7 %-3.3 %) for SAH to 6.4 % (6.0 %-6.7 %) for IS. CONCLUSION: Our results support the hypothesis that the prognosis of Chinese stroke patients appears to have improved and is not very bad.

Stroke-unit care for stroke patients in China: the results from Bigdata Observatory platform for Stroke of China.

BACKGROUND: To assess whether stroke patients admitted to stroke units (SU) have a better short-term outcome than those treated in conventional wards (CW). METHODS: A total of 20 hospitals from 16 provinces in China were initially selected in this study. Finally, 24,090 consecutive admissions in 2013-2015 treated in CW and 21,332 consecutive entries in 2017-2019 treated in SU were included. The primary endpoint of this study was the all-cause death or dependency condition three months after admission. RESULTS: Patients in the SU group were more likely receiving thrombolytic therapy (3.9 vs 2.1%) and intravascular treatment (1.2 and 0.7%). In-hospital death were lower in the SU group than the CW group (SU vs CW: 2.93 vs 4.58% [absolute difference, - 2.28% {95% CI, - 3.32% to - 0.93%}, odd ratio {OR}, 0.72{95% CI, 0.61 to 0.82}]. Death after discharge was also lower in the SU group than the CW (SU vs CW: 5.07 vs 6.72% [absolute difference, - 2.33% {95% CI, - 3.39% to - 0.90%}, odd ratio {OR}, 0.75{95% CI, 0.68 to 0.84}]. In addition, patients who received SU care were less likely to be dead or disabled than those patients who received CW care after adjusting for other variability (SU vs CW: 36.20 vs 44.33% [absolute difference, - 11.33% {95% CI, - 15.32% to - 7.14%}, odd ratio {OR}, 0.78{95% CI, 0.80 to 0.85}]. CONCLUSIONS: Among patients with stroke, admission to a designated SU was associated with modestly lower mortality at discharge, reduced probability of death, or being disabled at the end of follow-up.

Stroke prevention and control system in China: CSPPC-Stroke Program.

In China, stroke is a major cause of mortality, and long-term physical and cognitive impairment. To meet this challenge, the Ministry of Health China Stroke Prevention Project Committee (CSPPC) was established in April 2011. This committee actively promotes stroke prevention and control in China. With government financial support of 838.4 million CNY, 8.352 million people from 536 screening points in 31 provinces have received stroke screening and follow-up over the last seven years (2012-2018). In 2016, the CSPPC issued a plan to establish stroke centers. To shorten the pre-hospital period, the CSPPC established a stroke center network, stroke map, and stroke "Green Channel" to create three 1-h gold rescue circles, abbreviated as "1-1-1" (onset to call time <1 h; pre-hospital transfer time < 1 h, and door-to-needle time < 1 h). From 2017 to 2018, the median door-to-needle time dropped by 4.0% (95% confidence interval (CI), 1.4-9.4) from 50 min to 48 min, and the median onset-to-needle time dropped by 2.8% (95% CI, 0.4-5.2) from 180 min to 175 min. As of 31 December 2018, the CSPPC has established 380 stroke centers in mainland China. From 1 November 2018, the CSPPC has monitored the quality of stroke care in stroke center hospitals through the China Stroke Data Center Data Reporting Platform. The CSPPC Stroke program has led to a significant improvement in stroke care. This program needs to be further promoted nationwide.

Risk Factors for Incident Stroke and Its Subtypes in China: A Prospective Study.

Background Managing risk factors is crucial to prevent stroke. However, few cohort studies have evaluated socioeconomic factors together with conventional factors affecting incident stroke and its subtypes in China. Methods and Results A 2014 to 2016 prospective study from the China National Stroke Screening and Intervention Program comprised 437 318 adults aged ≥40 years without stroke at baseline. There were 2429 cases of first-ever stroke during a median follow-up period of 2.1 years, including 2206 ischemic strokes and 237 hemorrhagic strokes. The multivariable Cox regression analysis indicated that age 50 to 59 years (versus 40-49 years), primary school or no formal education (versus middle school), having >1 child (versus 1 child), living in Northeast, Central, East, or North China (versus Southwest China), physical inactivity, hypertension, diabetes mellitus, and obesity were positively associated with the risk of total and ischemic stroke, whereas age 60 to 69 years and living with spouse or children (versus living alone) were negatively associated with the risk of total and ischemic stroke. Men, vegetable-based diet, underweight, physical inactivity, hypertension, living in a high-income region, having Urban Resident Basic Medical Insurance, and New Rural Cooperative Medical System were positively associated with the risk of hemorrhagic stroke, whereas age 60 to 69 years was negatively associated with the risk of hemorrhagic stroke. Conclusions We identified socioeconomic factors that complement traditional risk factors for incident stroke and its subtypes, allowing targeting these factors to reduce stroke burden.

Stroke Center Care and Outcome: Results from the CSPPC Stroke Program.

The aim of this study was to assess the association between admission to stroke centers for acute ischemic stroke and complications and mortality during hospitalization in a Chinese population by means of an observational study using data from the China Stroke Center Data-Sharing Platform. We compared in-hospital complications and mortality for patients admitted with acute ischemic stroke (N = 13,236) between November 1, 2018 and December 31, 2018 at stroke center (SH) and non-stroke center (CH) hospitals using distance to hospitals as an instrumental variable to adjust for potential prehospital selection bias. The results showed that complication rates during hospitalization among ischemic stroke patients who received thrombolytic therapy (n = 11,203) were lower in the SH group than in the CH group: 11.1% vs 15.7% (absolute difference, - 5.11% [95% CI, - 6.05 to - 3.99%], odds ratio [OR] 0.85 [95% CI, 0.74 to 0.92]). The incidence of intracranial hemorrhage was reduced from 4.2 to 3.2%: SH group vs CH group, 3.2% vs 4.2% (absolute difference, - 1.24% [95% CI, - 1.65 to - 0.82%], OR 0.83 [95% CI, 0.69 to 0.0.98]). Furthermore, the total mortality rate in the SH group was also lower than in the CH group: SH group vs CH group, 2.2% vs 3.0% (absolute difference, - 0.92% [95% CI, - 1.48 to - 0.53%], OR 0.85 [95% CI, 0.73 to 0.96]). The data showed that admission to SH hospitals was associated with a lower risk of treatment complications and death for patients with an acute ischemic stroke receiving thrombolytic therapy.

Prevalence and risk factors of stroke in the elderly in Northern China: data from the National Stroke Screening Survey.

BACKGROUND: The overall global burden of stroke is considerable and increasing. In China, stroke is the leading cause of death and disability. METHODS: For this study, we used data from the National Stroke Screening Survey in 2012 and the 2010 Chinese population from sixth National Census of Populations to calculate a standardized (by age, gender, and education) stroke prevalence. Prevalence, risk factors, and management of stroke were compared by gender, age, and site. FINDINGS: The standardized prevalence rate of survival stroke patients in study population aged 60 and older was 4.94% in total. Hypertension was the most prevalent risk factor for stroke. Compared to men, women were more likely to have diabetes, obesity, elevated low-density lipoprotein cholesterol (LDL-C), and atrial fibrillation (P < 0.05). Men were far more likely to drink and smoke than women (P < 0.05). The rates of diabetes and atrial fibrillation were substantially higher in urban than those in rural stroke survivors (P < 0.05). Rural stroke survivors exhibited higher rates of smoking and alcohol consumption than urban stroke survivors (P < 0.05). INTERPRETATION: The stroke prevalence in China is in line with median worldwide stroke prevalence. Traditional risk factors remain highly prevalent in stroke survivors, among which hypertension was the most common. Stroke prevalence rates and risk factors varied by age, sex, and sociogeological factors.

Underuse of Oral Anticoagulants in Patients With Ischemic Stroke and Atrial Fibrillation in China.

Anticoagulant therapy is an effective stroke prevention measurement for subjects with atrial fibrillation (AF) who are at high risk of ischemic stroke. However, it is reported that oral anticoagulants (OACs) are generally underused in clinical practice. A better awareness of current usage of anticoagulant therapy would enable prevention of stroke secondary to AF. Therefore, we determined the nationwide prevalence of AF and the frequency of OACs use among patients with ischemic stroke in China. Based on the China National Stroke Screening Survey, a representative nationwide sample of 1,252,703 adults over 40 years old during 2013 and 2014 was involved. Information on demographic data, diagnosis of stroke, behavioral risk factors, family history of stroke, related diseases, and medications was collected. The community-based survey data showed that 5,588 patients (12.0%) with ischemic stroke had previous, or newly diagnosed, AF. Therefore, more than 2.15 million ischemic stroke patients had AF in China. Among ischemic stroke patients with AF, the strongest risk factor was coronary heart disease (odds ratio = 2.53), whereas dyslipidemia accounted for the largest contribution (population-attributable risk proportion = 17.33%). Of ischemic stroke patients with AF, only 2.2% had taken OACs; of them, 98.2% had taken warfarin. In conclusion, a large number of ischemic stroke patients with AF are significantly undertreated with OACs in China. This highlights the need for improvement of prevention of ischemic stroke secondary to AF.

Lifestyle Factors and Gender-Specific Risk of Stroke in Adults with Diabetes Mellitus: A Case-Control Study.

BACKGROUND: The lifestyle interventions are effective preventive measures for stroke in general population, and the stroke risk with lifestyle factors may be modified by gender, health conditions, etc. Therefore, we conducted a case-control study to investigate the gender-specific association between stroke risk and lifestyle factors in adults with diabetes based on the China National Stroke Screening Survey. METHODS: Structured questionnaires were used to collect demographic data and information regarding lifestyle factors, history of chronic medical conditions, and family history of stroke and the status of treatment. The case group comprised individuals diagnosed with first-ever stroke in 2013-2014 screening period. Their corresponding controls (frequency-matched for age group and urban/rural ratio) were randomly selected from individuals with diabetes without stroke. RESULTS: There were 170 total stroke cases (500 controls) and 152 ischemic stroke cases (456 controls) among men with diabetes, and 183 total stroke cases (549 controls) and 168 ischemic stroke cases (504 controls) among women with diabetes. We found that physical inactivity was significantly associated with increased risk of total stroke (odds ratio [OR] = 1.50, 95% confidence interval [CI] 1.02-2.21) and of ischemic stroke (OR = 1.57, 95% CI 1.04-2.36) in women with diabetes. We found no significant association of smoking, overweight/obesity, or physical inactivity with risk of total or ischemic stroke in men with diabetes. CONCLUSION: Among the lifestyle factors of smoking, overweight/obesity, and physical inactivity, physical inactivity might increase the risk of total and ischemic stroke in women with diabetes.

Rapid transitions in the epidemiology of stroke and its risk factors in China from 2002 to 2013.

OBJECTIVE: To estimate the current prevalence, temporal incidence trends, and contribution of risk factors for stroke in China. METHODS: The China National Stroke Screening Survey (CNSSS) is an ongoing nationwide population-based program. A representative sample of 1,292,010 adults over 40 years old with 31,188 identified stroke cases from the 2013 and 2014 CNSSS database was analyzed to provide descriptive statistics of the prevalence and risk factors for stroke in 2014. In addition, a retrospective evaluation of 12,526 first-ever stroke cases in 2002-2013 and stroke mortality data from the 2002-2013 China Public Health Statistical Yearbook was conducted to estimate the incidence rates. RESULTS: In 2014, the adjusted stroke prevalence was 2.06% in adults aged 40 years and older. After full adjustments, all risk factors assessed showed significant associations with stroke (p < 0.01); the largest contributor was hypertension (population-attributable risk 53.2%), followed by family history, dyslipidemia, atrial fibrillation, diabetes, physical inactivity, smoking, and overweight/obesity. The incidence of first-ever stroke in adults aged 40-74 years increased from 189/100,000 individuals in 2002 to 379/100,000 in 2013-an overall annual increase of 8.3%. Stroke-specific mortality in adults aged 40-74 years has remained stable, at approximately 124 deaths/100,000 individuals in both 2002 and 2013. CONCLUSIONS: In 2002-2013, the incidence of stroke in China increased rapidly. Combined with a high prevalence, a trend toward a younger age, and stable mortality, this finding suggests that additional clinical and behavioral interventions for metabolic and lifestyle risk factors are necessary to prevent stroke, particularly in certain populations.