A cohort study on the relationship between cerebrovascular hemodynamic changing and risk of stroke / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the role of cerebrovascular hemodynamic indexes (CVHI) changing in stroke and to provide reference for stroke prevention and risk factor study.</p><p><b>METHODS</b>From 2003 to 2004, participants aged 40 years and above in two communities in Fengxian district were recruited by cluster sampling. Risk factors of stroke and CVHI were investigated and checked during baseline investigation. A total of 10 565 individuals completed the survey and met the inclusion criterion. After baseline investigation, the cohort was followed up for stroke occurrence. Relative risk (RR) of CVHI and common risk factors were estimated by cohort study design.</p><p><b>RESULTS</b>Age of the cohort was (56.2 ± 11.4) years. 4444 (42.1%) were males and 6121 (57.9%) were females. Total follow-up duration was 67 885.7 person-years. A total of 195 stroke cases occurred and incidence density of stroke was 287.2 per 100 000 person-years. Stroke incidence in exposure groups of hypertension, heart disease and alcohol drinking was 3.47% (108/3118), 2.96% (21/710) and 2.50% (47/1882), respectively. The incidence in corresponding non-exposure group was 1.17% (87/7448), 1.77% (174/9855) and 1.70% (148/8683) respectively. There was significant difference between 2 groups (χ(2) value was 62.72, 4.56 and 4.94, respectively, P < 0.05). Stroke incidence in CVHI score < 25, 25 - 49, 50 - 74 and ≥ 75 groups was 9.12% (59/647), 5.68% (44/775), 2.52% (39/1545) and 0.72% (53/7403)(χ(2)trend = 273.57, P < 0.05), respectively. Incidence of stroke in 40 - 49, 50 - 59, 60 - 69, ≥ 70 years age group was 0.22% (8/3565), 1.28% (43/3357), 2.71% (50/1848) and 5.88% (94/1600) (χ(2)trend = 181.48, P < 0.05), respectively. Multiple Cox regression analysis indicated that RR (95%CI) value of hypertension and cigarette smoking was 1.40(1.02 - 1.92) and 1.59(1.19 - 2.12), respectively when comparing with non-exposure group. RR (95%CI) value in CVHI score < 25, 25 - 49 and 50 - 74 points group were 6.15 (4.08 - 9.26), 4.55 (2.98 - 6.96) and 2.68 (1.75 - 4.09), respectively when comparing with the score ≥ 75 points group. RR (95%CI) value in age 50 - 59, 60 - 69 and ≥ 70 years group was 4.61 (2.16 - 9.82), 7.81 (3.67 - 16.60) and 13.49(6.44 - 28.24), respectively when comparing with below 40 years group.</p><p><b>CONCLUSION</b>CVHI score is the strong independent predictive factor and hypertension, cigarette smoking and age are the independent risk factors of stroke.</p>

Monitoring of stroke morbidity and mortality in 2 rural communities of Shanghai from 2008 to 2010 / 中国脑血管病杂志

Objectives: To monitor stroke morbidity and mortality in 2 rural communities of Shanghai and to provide a reference for stroke prevention and epidemiological study. Methods: A modified cluster-sampling method was used to extract about 100 000 natural populations in the 2 communities of Fengxian District, Shanghai. The demographic data were collected annually. In the monitored populations, the tertiary monitoring network was established to investigate the morbidity and mortality of stroke, and to analyze and monitor the morbidity and mortality and the distribution of clinical types of stroke in the populations from 2008 to 2010. The morbidity and mortality of stroke were adjusted by the National Population Sample Survey 2009. Results: Circled digit oneA total of 100 622 subjects were monitored from 2008, and 304 306 person times were monitored cumulatively up to 2010. A total of 585 subjects had first attack of strokes and 313 died. The morbidity in the 3 years was 275.3/100 000, 173.5/100 000 and 129.3/100 000, respectively, and the average annual stroke morbidity was 192.2/100 000; the standardized morbidity was 180.7/100 000, 115.3/100 000 and 81.7/100 000, respectively. The stroke mortality was 113.3/100 000, 102.1/100 000 and 93.3/100 000, respectively. The average annual stroke mortality was 102.9/100 000; the standardized mortality was 73.5/100 000, 67.5/100 000 and 57.2/100 000, respectively. Circled digit twoIn the <45, <45 to 64 and ≥65 age groups, the average annual morbidity was 4.9/100 000, 122.8/100 000 and 913.8/100 000, respectively, and the average annual mortality was 2.8/100 000, 22.6/100 000 and 591.8/100 000, respectively. The differences were statistically significant (P < 0.01). Circled digit threeThere was no significant difference in the average annual morbidity and mortality between the genders. In the 45 to 64 age group, the average annual morbidity and mortality were 156.7/100 000 and 32.0/100 000 in males; while the average annual morbidity and mortality were 90.4/100 000 and 13.6/100 000 in females. The differences were statistically significances (P < 0.01). Circled digit fourThe constituent ratios of intracerebral hemorrhage, cerebral infarction, subarachnoid hemorrhage and unclassified stroke were 22.6%, 75.7%, 0.9% and 0. 9%, respectively. Conclusion: The stroke morbidity and mortality in the rural communities of Shanghai are 192.2/100 000 and 102.9/100 000. The morbidity and mortality increased with age. The stroke morbidity and mortality in males is higher than those in females in the 45 to 64 age group. The proportion of patients with cerebral infarction is significantly higher than intracerebral hemorrhage.

Study on over-weight, obesity and the exposure to stroke risk factors among 40 year olds and over in a community-based population / 中华流行病学杂志

Objective To describe the distribution of over weight and obesity to discover the level of exposure on risk factors of stroke among people aged 40 and over, in a community-based population.Methods From 2003 to 2004, people aged t≥40 years in a community of Fengxian district in Shanghai were selected by cluster sampling. Out of 11 791 individuals who were selected, 10 565 met the inclusion criteria and responded to the investigation. By face to face interview, a cross-sectional survey was carried out, using a questionnaire for risk factors of stroke. Height, weight and blood pressures were measured and cerebrovascular hemodynamic parameters (CVHP) were checked. Age and gender distribution of over weight and obesity in the population were described. Using 60 year as cut-off point, participants were grouped into three: normal, over weight and obesity by body mass index. Level of stroke risk factor exposure between groups was compared and logistic regression model was used for multiple analyses. Results Proportions of over weight and obesity were 28.5 percent and 4.1 percent in male and 26.3 percent and 4.2 percent in female (P=0.045 ). Systolic and diastolic blood pressure in over weight group were (132.5±19.4)ram Hg and (83.9±10.5)mm Hg(1 mm Hg= 0.133 kPa),which were higher than that in normal weight group and lower than that in obese group (P<0.05). Exposure rate of heart disease,family history of stroke in < 60 year old group and diabetes in ≥60 year group increased along with the increase of weight. Exposure rate of hypertension, abnormality of CVHP score in both age groups were also increased with the increase of weight. Data from multiple logistic regression indicated that hypertension,family history of stroke and heart disease, CVHP score below 75 points, sex and age were independent factors of over weight and obese. Conclusion The prevalence of over weight or obesity in a community-based population among aged 40 years or over was around 30 percent. The overall exposure rate of stroke risk factors were increasing along with the increase of weight, especially for those in the middle age.

Baseline study and analysis on a stroke risk factor-related cohort in Fengxian county of Shanghai / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the exposed level of stroke risk factors in Fengxian county of Shanghai and the relationships between risk factors and stroke.</p><p><b>METHODS</b>Community based populations including 10,565 individuals aged 40 years old and over were cluster sampled from Fengxian county in 2003 or 2004. Status of exposure on common risk factors such as hypertension, cardiovascular disease, diabetes, family history of stroke, cigarette smoking, alcohol intake were gathered while cerebral vascular hemodynamic index (CVHI) was examined, with CVHI score below 75 points as abnormal. During 2003 to 2006, 78 stroke cases occurred. The relationships between risk factors and stroke were analyzed by univariate and Cox proportional hazards regression models.</p><p><b>RESULTS</b>Rates of exposure regarding hypertension, cardiovascular disease, diabetes, family history of stroke, obesity (BMI > or = 28 kg/m2), smoking, drinking and CVHI score abnormal were 21.14%, 6.72%, 1.88%, 5.63%, 4.17%, 34.96%, 17.81% and 29.43%, respectively. Data from Univariate analysis indicated that relative risk (95% CI) of above-mentioned risk factors were 2.76 (1.76-4.32), 2.19 (1.16-4.14), 1.52 (0.38-6.19), 1.58 (0.69-3.62), 1.24 (0.45-3.38), 1.75 (1.12-2.73), 2.10 (1.30-3.39) and 12.72 (7.02-23.06), respectively. Results from Cox proportional hazards regression models analysis showed that cigarette smoking, CVHI score abnormal were screened into equation.</p><p><b>CONCLUSION</b>Among all the risk factors, rate of hypertension was the highest while hypertension, cardiovascular disease, cigarette smoking, alcohol intake and abnomal CVHI score had remarkable etiological correlations to stroke. Abnormal CVHI score, cigarette smoking seemed to be the independent forecasting factors related to stroke.</p>

Evaluation on the indirect economic burden of stroke using combination of disability-adjusted life years and human capital method / 中华流行病学杂志

<p><b>OBJECTIVE</b>Using the indirect economic burden of stroke in a rural population to develop rational allocation of future health resources, in Hanzhong area.</p><p><b>METHODS</b>Cluster sampling which involved 53 natural villages with a total number of 75,000 people selected from the 'stroke monitoring base' of rural population was adopted in this study in the Hanzhong area. All of the 164 stroke cases were studied through a self-designed questionnaire. In calculating disability-adjusted life years (DALYs), fixed value was used in accordance with the value of GBD. The disability assessment was simplified in DALYs calculation and modified Barthel's ADL was used in disability assessment of stroke patients. In indirect economic burden analysis, the human capital method combined with DALYs was adopted with the formula as: indirect economic burden = GNP per capita x DALYs x productivity weight.</p><p><b>RESULTS</b>The total DALYs were 598.88, with an average DALY of stroke as 3.65 per case. The total indirect economic burden of stroke patients in rural areas was 1,993,977.8 RMB and the average of indirect economic burden of stroke was 12,158.4 RMB per case with the largest seen in the 45-59 age group, accounted for 74.4%.</p><p><b>CONCLUSION</b>In our study, the use of method in combining the human capital with DALYs was the first time being adopted in calculation of the indirect economic burden of stroke in rural population in China. The burden seemed to be much lower than literature cited from other countries. It was reasonable to evaluate indirect economic burden of stroke using method in integrating DALYs with human capital, but it was difficult to calculate the DALYs.</p>

Baseline study on a stroke-related cohort in the rural community of Shanghai / 中华流行病学杂志

<p><b>OBJECTIVE</b>To present data from a baseline investigation on stroke-related cohort population in rural area of Shanghai.</p><p><b>METHODS</b>A cross-sectional study was carried out in a cluster sampling population aged 40 years and over. General information and data on common risk factors in the population were gathered and cerebral vascular hemodynamic indexes were checked. Hemodynamic score was estimated according to single indexes by unified methods. 5335 persons who had met the inclusion criteria were enlisted in the study. Exposure level of risk factors, prevalence of stroke, and hemodynamic indexes were analyzed and distributional characteristics were described.</p><p><b>RESULTS</b>Exposure rate of hypertension, heart disease, diabetes, family history of hypertension, overweight or obesity in males were 31.74%, 6.09%, 1.16%, 3.22%, 17.64%, 29.68% and were 32.76%, 9.22%, 1.55%, 3.84%, 19.22%, 29.44% in female respectively. Standard prevalence of stroke was 1167.3/100000, which in male was significantly higher than that in female (P < 0.05). The change of cerebral vascular hemodynamic indexes was significantly associated with age. Hemodynamic score in 21.3% of the subjects was below 75 points.</p><p><b>CONCLUSIONS</b>Among population of 40 years old and over in rural areas, hypertension was the principal risk factor regarding the rate of stroke. Prevalence of stroke in males was significantly higher than that in females. Abnormal rate of hemodynamic score was about 20% in this population.</p>

Effectiveness of Nao'an Capsule on stroke prevention among high risk population in Nanhui, Shanghai / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the effectiveness of stroke prevention among high risk population, using Nao'an Capsules.</p><p><b>METHODS</b>Participants were selected from 696,558 residents in Nanhui, using county of Shanghai city. Individuals aged 35 years old and over with at least one risk factor exposure to stroke, received cerebral vascular hemodynamic examination. 18,271 cases meeting the criteria of cerebral vascular hemodynamic indexes accumulative score below 70 points were defined as individuals with high-risk and targets to receive intervention. According to the willingness of the participants, 10,313 cases received Nao'an Capsules for intensive intervention based on general intervention measures compared to 7958 cases only receiving general intervention. After the implementation of intervention, incidence and mortality rates of stroke and the effectiveness of three-year intervention were studied.</p><p><b>RESULTS</b>Incidence of stroke in Nao'an Capsules group was significantly lower than that of the general intervention (P < 0.01) with 53.8% in males and 58.4% in females. The relative risk (RR) in two gender groups were 0.46 (0.33 - 0.64) and 0.39 (0.30 - 0.50) respectively. Multiple logistic regression analysis indicated that the history of hypertension, accumulative score of cerebral vascular hemodynamic indexes, age, gender and Nao'an Capsules intervention were the variables selected into the equation and significantly related to stroke. Among the variables, Nao'an Capsule was the strongest factor with a RR of 0.41.</p><p><b>CONCLUSION</b>Incidence of stroke in Nao'an Capsule intervention group was significantly lower than that in the general intervention group after 3 years of intervention, suggesting that Nao'an Capsule intervention was the strongest factor affecting stroke occurrence in individuals at high-risk.</p>

Analysis on direct economic burden of stroke in the rural population of Hanzhong, Shaanxi Province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To analyze the direct economic burden of stroke in rural areas of Hanzhong.</p><p><b>METHODS</b>Plan on primary interview was made after the purpose of the study had been informed to the managers of the 'surveillance field base', heads and members of the monitor assistants and detailed information was collected in the fields. Every single patient of stroke was then interviewed by the above said interviewers,using a self-designed questionnaire. 164 patients with stroke were interviewed in 53 villages with 75,000 persons lived there. The main items involved in the questionnaire would include: costs for inpatient or outpatient, reaching-out fees, fee for accommodation during treatment as outpatient, costs for treatment at home, long term medicine, caregivers and funerals as well as average income.</p><p><b>RESULTS</b>The median of annual direct economic burden was 3100 Yuan for each patient in Hanzhong rural area. There were no significant differences seen between males and females or among age groups (P > 0.05). The proportion of patients with medians of annual direct economic burden of: 1000 Yuan and below, 1001-5000 Yuan, 5001-10,000 Yuan, 10,001-20,000 Yuan and over 20,001 Yuan, were 29.2%, 36.0%, 18.3%, 9.8% and 6.0% respectively. The median of annual direct economic burden of first episode stroke was 5500 Yuan for each patient, and that of stroke was 1700 Yuan for each chronic patient. The direct economic burden of first episode was significantly higher than that of stroke (P < 0.01). The costs of hospitalization, accommodation of hospitalization and treatment at home of middle-aged patients were significant higher than that of old age patients (P < 0.05).</p><p><b>CONCLUSION</b>In this study, the direct economic burden of stroke was 2.9 times of the annual personal average income, which was contrary to the reports from other countries. However, the State Health Bureau bore 87.1% of the direct economic burden for urban patients, but patients in the rural areas had to pay from their own pockets. The direct economic burden of stroke was heavy in Hanzhong rural region, which called for measures to be made to decrease the direct economic burden of stroke in the region.</p>

The relationship between hypertension and cerebral hemodynamic scores of vascular function accumulative / 中华流行病学杂志

<p><b>OBJECTIVE</b>To probe into the relationship between hypertension and hemodynamic score of cerebral vascular accumulative function by though studying the history of hypertension and level of blood pressure.</p><p><b>METHODS</b>The database of blood pressure and cerebral vascular hemodynamic indexes (CVHI) were from baseline data and measurement in a cohort. 18,512 participants who met the included criteria were enlisted in the study. The function scores were estimated using uniform methods according to CVHI. Participants were grouped by age, years of having hypertension and level of blood pressure. Differences of the function score between different groups were compared.</p><p><b>RESULTS</b>The function score in hypertension group was significantly lower than that of normal tension group, which decreased by 13.3 points. Within 5 years of hypertension history, the function score decreased as course of hypertension prolonged. The same trend was found between the score and level of both systolic and diastolic blood pressure. When systolic blood pressure elevated to 140 mmHg or diastolic blood pressure elevated to 95 mmHg, the function score was below 75 points.</p><p><b>CONCLUSION</b>There were significant relationship between decrease of the function scores and medical history, course of hypertension as well as level of blood pressure.</p>

Study on the application of the Chinese version of SF-36 scales and selection of interceptive cents for its grade range / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the possibility of measuring quality of life by Medical Outcomes Study 36-Item Short-Form Health Survey scale and to subdivide grade range of Medical Outcomes Study 36-Item Short-From Health Survey (SF-36) total cents through a Quality of Life questionnaire among the elderly Chinese.</p><p><b>METHODS</b>The quality of life of the 167 elderly Chinese in Suzhou was measured simultaneously by SF-36 and the Quality of Life questionnaire developed by Epidemiology Group of Geriatric Medicine Committee of China for the elderly. Validity and reliability were analyzed and subdivided the grade range of SF-36 total scores by Quality of Life questionnaire for the Chinese elderly.</p><p><b>RESULTS</b>Eight common factors from factorial analysis were in accordance with their theoretical structure, and the cumulative contribution rates of the Quality of Life questionnaire for the elderly and SF-36 were 74.244% and 72.081%. The split-half reliability of the Quality of Life questionnaire for the elderly was 0.6676. The split-half reliability of SF-36 was 0.9384. In SF-36, the Cronbach's alpha coefficient of internal consistency reliability ranged from 0.81 to 0.89, which was satisfactory for group comparison except 0.63 for the social functioning and 0.42 for mental health scale and 0.69 for vitality scale. The Quality of Life questionnaire for old people seemed to have good validity and reliability but the SF-36 was better. The cent of the furthest truncation between the good quality of life and the medium one in the SF-36 was 117 with a Kappa value of 0.58.</p><p><b>CONCLUSION</b>The SF-36 scale could be used for measuring and evaluating the quality of life for the Chinese elderly. The cent of the furthest truncation could provide reference to judge the level of the quality of life of the elderly.</p>

Study on mortality, incidence and risk factors of stroke in a cohort of elderly in Xi'an, China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To prospectively study the relationship between risk factors and stroke incidence and mortality in the Chinese elderly.</p><p><b>METHODS</b>An analytic study in a cohort population of 1,268 male retired cadres in a military setting. A health-screening program was carried out for all cadres aged 55 years or older in Xi'an in February 1987. Baseline data on smoking, cholesterol, triglyceride, blood pressure, body mass index (BMI), histories of hypertension, hyperlipidemia and coronary heart disease (CHD), stroke, diabetes and family histories of cardiovascular disease were investigated. Main outcome measures were stroke incidence, stroke and all-cause mortality.</p><p><b>RESULTS</b>The cohort was followed up until June 30, 2001 and a total number of follow-up person-year was 15,546. During the follow-up period, there were 113 new stroke cases identified and the adjusted incidence was 727 per 100,000 person-year. Forty-five deaths were due to stroke and the adjusted mortality was 289 per 100,000 person-year. Using Cox model analysis, after adjustment on age, total cholesterol, triglyceride, smoking, drinking and physical exercise, we noticed that the systolic pressure, BMI, history of CHD and hyperlipidemia were independent risk factors for stroke incidence and morality.</p><p><b>CONCLUSION</b>The incidence and mortality of stroke in this cohort were lower than those in the same age group of general population. Monitoring and controlling body mass index and blood pressure level seemed to be important factors for the prevention of stroke in the elderly.</p>

Principal component analysis and integral methods of cerebral vascular hemodynamic parameters / 中华流行病学杂志

<p><b>OBJECTIVE</b>To establish a predicting model for stroke according to cerebral vascular hemodynamic indexes and major risk factors of stroke.</p><p><b>METHODS</b>Participants selected from a stroke cohort with 25,355 population in China. The first step was to carry out principal component analysis using CVHI. Logistic regression with principal component and main risk factors of stroke were then served as independent variables and stroke come on as dependent variables. The predictive model was established according to coefficient of regression and probability of each participant was also estimated. Finally, ROC curve was protracted and predictive efficacy was measured.</p><p><b>RESULTS</b>The accumulative contribution rates of four principal components were 58.1%, 79.4%, 88.4% and 94.6% respectively. Seven variables were being selected into the equation with the first to fourth principal component as history of hypertension, age and sex. Area under ROC curve was 0.855 and optimal cut-off point was probability over 0.05. Sensitivity, specificity and accuracy of stroke prediction were 80.7%, 78.5% and 78.5% respectively.</p><p><b>CONCLUSION</b>The model established by principal component and regression could effectively predict the incidence of stroke coming on.</p>

A cohort study on cerebral vascular hemodynamics accumulative score and risks of stroke / 中华流行病学杂志

<p><b>OBJECTIVE</b>To estimate relative risk (RR) of cerebral vascular hemodynamics indexes (CVHI) accumulative score as well as some other risk factors of stroke.</p><p><b>METHODS</b>A cohort study was carried out in 25 355 participants aged 35 and over in Northeast of China from 1994 to 2001. In the baseline survey, exposure rates of hypertension, diabetes, family history of stroke and hypertension, etc. were collected and CVHI was examined. CVHI accumulative score was synthesized according to contribution of single index. During the 7-year following up, 228 stroke cases were identified and stroke coming on was defined as the endpoint of observation. Uni-variable and multiple variables analysis were carried out for estimating RR of CVHI and other risk factors of stroke.</p><p><b>RESULTS</b>Uni-variables analysis indicated that RR (95% confidence interval, CI) of Hypertension, heart diseases, diabetes, family history of hypertension and stroke, overweight or obesity, alcohol intake, cigarette smoking and CVHI < 75 scores were 3.23 (2.48 - 4.20), 2.53 (1.92 - 3.33), 2.38 (1.55 - 3.64), 1.32 (1.02 - 1.72), 1.82 (1.37 - 2.41), 1.62 (1.25 - 2.11), 1.48 (1.07 - 2.04), 1.76 (1.34 - 2.31) and 7.30 (5.43 - 9.80) respectively. Cox regression analysis showed that CVHI below 75 points, family history of stroke, cigarette smoking, heart disease, hypertension, age and sex were the factors being selected in equation. There was a significant dosage response between the decrease of CVHI score and the increase of stroke risk. RR of stroke reached 12.55 when CVHI below 75 points and history of hypertension appeared in the same individuals.</p><p><b>CONCLUSION</b>Abnormality of CVHI score seemed to be the most important and independent factor among stroke risk factors. Decrease of CVHI score might serve as a marker of high risk and play important role in stroke, especially coexistence with hypertension.</p>