Current application of placebo in Chinese clinical studies in past 30 years / 中国中药杂志

To analyze and discuss placebo-related information in clinical research literatures in the past 30 years, including placebo's dosage form, ingredients, preparation process and quality control. Effort were made to research the CNKI. full-text database to preliminary find 700 placebo-related clinical research literature, screen out 301 eligible articles by hand, read the literatures to extract placebo-related information and make statistics and discussions. According to the results, Chinese randomized placebo-controlled clinical studies were characterized by diverse dosage forms of placebo with lack of reports for components, as evidenced by the only 17 literatures describing placebo's preparation or specific composition among the 301 literatures. Placebo-controlled clinical trials covered a wide range of disease spectra, but with a specific tropism of diseases in terms of system classification. Although placebo plays a key role in blinded clinical studies, researchers made less records of placebo, perhaps because they paid less attention to placebo or more attention to the research process or restricted by other objective conditions. Moreover, placebo production, quality control and quality evaluation also need to be further standardized.

Prospective study on associations between levels of total cholesterol, triglyceride and risk of ischemic and hemorrhagic strokes / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore associations between levels of total cholesterol (TC), triglyceride (TG) and incidence of ischemic and hemorrhagic strokes in populations.</p><p><b>METHODS</b>Baseline investigations on stroke-related risk factors and physical examinations were performed in 10 093 (> 35 years) stroke-free urban community residents from 5 cities in China during May to July in 1987, follow-up investigations on stroke events were made during 1998 to 2000. The hazard ratios and 95% confidence intervals (CI) of ischemic and hemorrhagic strokes in middle, high tertiles of baseline TC or TG levels were compared with low baseline tertile residents using the Cox regression model.</p><p><b>RESULTS</b>There were 491 first strokes during the 8-years cohort follow-up. Compared with the low tertile, risk of ischemic stroke in the middle and high tertiles of TC level was increased by 61% (HR: 1.61, 95%CI: 1.14-2.27) and 58% (HR: 1.58, 95%CI: 1.12-2.22) after adjustments for DBP, age, sex and other variables in the Cox proportional hazards model. Compared with the low tertile, risk of ischemic stroke in the high tertile of TG level was increased by 43% (HR: 1.43, 95%CI: 1.02-2.00). However, risk of hemorrhagic stroke in the middle and high tertiles of TC level decreased by 12% (HR: 0.88, 95%CI: 0.64-1.22) and 33% (HR: 0.67, 95%CI: 0.48-0.95) compared with the low tertile.</p><p><b>CONCLUSIONS</b>Elevated serum TC and TG are independent risk factors for risk of ischemic stroke. However, low TC was related with increased risk of hemorrhagic stroke.</p>

Study on the relationship between hypertension management and the risk of stroke at community level / 中华流行病学杂志

<p><b>OBJECTIVE</b>To observe whether the community-based management for patients with hypertension can reduce the incidence of stroke.</p><p><b>METHODS</b>Sample of this study included 36 863 people aged 35 years or more who came from a cohort consisting three communities from Tiantan Hospital, Puren Hospital and the Gymnasium Road Hospital in Beijing, based on the surveys on the Integrated Community Intervention Measures of Cerebro-vascular Diseases. Some patients with hypertension in this cohort were followed up and under management. First-ever stroke was considered as the end-point event.</p><p><b>RESULTS</b>In both groups diagnosed as borderline hypertension or definite hypertension group, the rates of management and control showed an annual increase. The management rate for women was higher, but the control rate was lower (P < 0.05) than that for men. In the third year of this study, the control rate was nearly 18%. With the qualification of control rate, the risk factors of overall stroke, ischemic stroke or hemorrhagic stroke reduced gradually, and the qualification of control rate showed more effects on hemorrhagic stroke. The qualification of control rate in the three years could cause the risk factors of total stroke, ischemic stroke or hemorrhagic stroke to reduce by 25.7%, 19.1%, 27.4%, respectively. When comparing with blood pressure level at < 160/95 mm Hg (1 mm Hg = 0.133 kPa), the level of < 140/90 mm Hg could reduce the risk factors as: 12.3% to total stroke, 12.8% to ischemic stroke and 14.9% to hemorrhagic stroke.</p><p><b>CONCLUSION</b>Programs as long-term followed-up and management for patients with hypertension, and control the blood pressure at low level etc. could significantly reduce the incidence of stroke.</p>

Evaluation on a community-based intervention program among people with different risk factors of stroke / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the effect of a long-term community-based intervention program on risk factors of stroke among people with different risk factors.</p><p><b>METHODS</b>In 1987,2 geographically separated communities with 10 000 registered residents of each, were selected as either intervention or control communities in Beijing and Changsha. A cohort containing 2700 subjects at the age of 35 years or older,and free of stroke were sampled from each community. The baseline survey was conducted to screen the subjects at high risk for intervention and there were 5319 and 5506 subjects enrolled in intervention and control cohorts,respectively. Then,a program for controlling the risk factors of stroke was initiated in the intervention cohort and health education was provided to the whole intervention community. A follow-up survey was conducted in 1999. The information on incidence and mortality of stroke was collected.</p><p><b>RESULTS</b>Comparing with the control cohort, the risk of incidence and mortality of stroke decreased by 22 % ( HR = 0.78,95 % CI:0. 66-0.92) and 73 % (HR = 0.27,95 % CI:0. 17-0.42) in intervention cohort. The risks of stroke were lower in intervention cohort than in control cohort among almost all of the sub-groups with or without risk factors of stroke except for being male,current smokers and current alcohol drinkers. The risk of death caused by stroke decreased significantly in those with or without the risk factors of stroke.</p><p><b>CONCLUSION</b>The long-term community intervention on the risk factors of stroke could effectively reduce the risk of incidence and mortality of stroke among people with or without the risk factors of stroke. More attention should be paid to the males and those who smoke or drink alcohol.</p>

Community intervention on hypertension and stroke / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the community-based intervention on reduction of hypertension and stroke in different age groups and subtypes hypertension.</p><p><b>METHODS</b>In 6 cities, 2 geographically separated communities with a registered population about 10 000 of each were selected as either intervention or control communities. A cohort containing 2 700 subjects, 35 years or older, and free of stroke were sampled from each community. The baseline survey was conducted to screen the subjects for intervention. In each city, a program for control of hypertension, heart diseases and diabetes was initiated in the intervention cohort and health education was provided to the whole intervention community. A follow-up survey was conducted 3 years later.</p><p><b>RESULTS</b>Within 3 years, the prevalence of hypertension increased in both intervention and control cohorts, as well as in the middle and elderly cohorts, especially in the middle aged in control group. Among hypertensives in the intervention cohort, the rates of awareness, treatment and control of hypertension got improved. The incidence of stroke was 29% lower (HR = 0.71, 95% CI: 0.58 - 0.87) and mortality of stroke was 40% lower (HR = 0.60, 95% CI: 0.42 - 0.86) in the intervention cohort than the control cohort. The intervention was most effective in reduction of stroke for those with isolated systolic hypertension and combined systolic and diastolic hypertension (All P < 0.05). Meanwhile, all-cause mortality was 11% lower (HR = 0.89, 95% CI: 0.78 - 0.99) in the intervention cohort than in the control cohort.</p><p><b>CONCLUSION</b>The community-based intervention was effective in controlling the development of hypertension and stroke, while the elderly people benefit more than the middle aged people from the intervention.</p>

Evaluation of effectiveness of intervention on risk factors for cerebrovascular disease in three cities of China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluate the effects of community intervention on risk factors of cerebrovascular disease.</p><p><b>METHODS</b>With cluster sampling, 2,586 and 2,723 women and men aged 35 to 74 were selected randomly as intervention cohort and control cohort, respectively, from about 300 thousand community population in Beijing, Shanghai and Changsha, during 1997 to 2000. Their blood pressure, levels of blood lipid, body mass index (BMI) were measured and status of smoking and alcohol consumption were surveyed as indices of evaluation. Health education for smoking quit, alcohol consumption restriction and reinforced treatment for diabetic and hypertensive patients were implemented in the intervention communities. And, 2,544 and 2,533 persons in the two cohorts responded three years after intervention, and then all the indices mentioned above were measure again for them.</p><p><b>RESULTS</b>Average reduction in systolic blood pressure by 3.21 mm Hg and serum level of total cholesterol by 0.58 mmol/L was achieved in intervention cohort after intervention, but with 0.48 mmol/L increase in triglyceride. Average blood levels of both high density lipoprotein-cholesterol (HDL-C) and glucose increased in the two cohorts after intervention, but with 0.30 mmol/L net increase of blood glucose in control cohort. There was no significant difference in average increase of HDL-C between the two cohorts. BMI increased by 0.56 in control cohort, and no significant change in intervention cohort. Proportion of smoking decreased by 5.4% in men and 2.4% in women of intervention cohort, and no change in control cohort.</p><p><b>CONCLUSION</b>Level of risk factors for cerebrovascular disease reduced significantly with community intervention.</p>