OBJECTIVEUsing case-crossover design to estimate the acute effect of ambient air pollution on daily mortality in Shanghai, and to explore the applicability of if in studying the acute health effects of air pollution.

METHODSCase-crossover technique was used to evaluate the relationship between air pollution and daily mortality from June 2000 to December 2001 in Shanghai. The results of the bi-directional control sampling approach were compared with unidirectional approach.

RESULTSThe validity of relative risks in case-crossover studies varied greatly depending on the strategy used in control sampling. When a bi-directional six control sampling approach was used an increase of relative risk of non-accident mortality on each 10 micro g/m(3) over a 48-hr moving average of PM(10), SO(2) and NO(2) corresponds to 1.003 (95% CI: 1.001 - 1.005), 1.016 (95% CI: 1.011 - 1.021), and 1.020 (95% CI: 1.012 - 1.027) respectively was seen.

CONCLUSIONThe results reinforced the deleterious role of current air pollution level on human health in Shanghai, and provided information on the applicability of case-crossover design in studying the acute health effects of air pollution.

Air Pollution ; adverse effects ; Cardiovascular Diseases ; etiology ; Cross-Over Studies ; Humans ; Logistic Models ; Mortality ; Pulmonary Disease, Chronic Obstructive ; etiology

OBJECTIVETo evaluate the risk factors for peripheral arterial disease (PAD) and the relationship of low ankle brachial index (ABI) to all-cause and cardiovascular disease (CVD) mortality in Chinese male patients with hypertension.

METHODSThe data of 1606 male participants with hypertension from the eight hospitals in Beijing and Shanghai were analyzed. ABI was ascertained at baseline by measuring the systolic pressures on bilateral brachial and tibial arteries. ABI < or = 0.9 was used as the diagnostic criteria for PAD identification. The follow-up survey was conducted from November 2005 to January 2006.

RESULTSOf 1606 male participants with hypertension at baseline, 406 (25.3% ) were in low-ABI group and 1200 (74.7%) were in normal-ABI group. Older age, TC, history of diabetes, history of smoking and 2-grade hypertension were associated with low ABI in male patients with hypertension. During the (12.87 +/- 2.94) months follow-up, there were 153 deaths. Of which, 62 were attributable to CVD. Low ABI was associated with adjusted all-cause and CVD mortality risk of 1.728 (1.223-2.441) and 2.388 (1.409-4.046) respectively in Cox regression models. Rate of survival for the low-ABI group was significantly worse than for the normal-ABI group. The risk of all-cause and CVD mortality was increased with the decline of ABI.

CONCLUSIONLow ABI is independently associated with the high risks of all-cause and CVD mortality in Chinese male patients with hypertension. The utility of ABI as a tool for predicting mortality in the patients with hypertension should be popularized.

Ankle Brachial Index ; Cardiovascular Diseases ; mortality ; China ; Follow-Up Studies ; Humans ; Hypertension ; epidemiology ; etiology ; Male ; Risk Factors

BACKGROUNDEarly onset severe preeclampsia is a specific type of severe preeclampsia, which causes high morbidity and mortality of both mothers and fetus. This study aimed to investigate the clinical definition, features, treatment, outcome and risk factors of early onset severe preeclampsia in Chinese women.

METHODSFour hundred and thirteen women with severe preeclampsia from June 2006 to June 2009 were divided into three groups according to the gestational age at the onset of preeclampsia as follows: group A (less than 32 weeks, 73 cases), group B (between 32 and 34 weeks, 71 cases), and group C (greater than 34 weeks, 269 cases). The demographic characteristics of the subjects, complications, delivery modes and outcome of pregnancy were analyzed retrospectively.

RESULTSThe systolic blood pressure at admission and the incidence of severe complications were significantly lower in group C than those in groups A and B, prolonged gestational weeks and days of hospitalization were significantly shorter in group C than those in groups A and B. Liver and kidney dysfunction, pleural and peritoneal effusion, placental abruption and postpartum hemorrhage were more likely to occur in group A compared with the other two groups. Twenty-four-hour urine protein levels at admission, intrauterine fetal death and days of hospitalization were risk factors that affected complications of severe preeclampsia. Gestational week at admission and delivery week were also risk factors that affected perinatal outcome.

CONCLUSIONSEarly onset severe preeclampsia should be defined as occurring before 34 weeks, and it is featured by more maternal complications and a worse perinatal prognosis compared with that defined as occurring after 34 weeks. Independent risk factors should be used to tailor the optimized individual treatment plan, to balance both maternal and neonatal safety.

Adult ; Cardiovascular Diseases ; epidemiology ; etiology ; Female ; Fetal Death ; Gestational Age ; Humans ; Pre-Eclampsia ; epidemiology ; mortality ; Pregnancy ; Pregnancy Complications ; epidemiology ; mortality ; Risk Factors

OBJECTIVETo obtain the exposure-response functions that could be used in health-based risk assessment of particulate air pollution in China.

METHODSMeta analysis was conducted on the literatures on air particulate matter and its adverse health outcomes in China and worldwide.

RESULTSFor each health outcome from morbidity to mortality changes, the relative risks were estimated when the concentration of air particulate matter increased to some certain units.

CONCLUSIONThe exposure-response functions recommended here can be further applied to health risk assessment of air particulate matter in China.

Acute Disease ; Adult ; Air Pollutants ; adverse effects ; toxicity ; Asthma ; epidemiology ; etiology ; Bronchitis ; epidemiology ; etiology ; Bronchitis, Chronic ; epidemiology ; etiology ; Cardiovascular Diseases ; epidemiology ; etiology ; Child ; China ; Dust ; Environmental Exposure ; Hospitalization ; Humans ; Mortality ; Particle Size ; Risk ; Risk Assessment

BACKGROUNDIncreased blood pressure and elevated total cholesterol (TC) level are the two most important modifiable risk factors of cardiovascular disease (CVD) in the world. Hypertension and hypercholesterolemia co-exist more often than would be expected and whether there is a synergistic impact on fatal CVD between elevated TC and hypertension need to be further examined in Chinese population.

METHODSWe conducted a cohort study which recruited 5092 Chinese male steelworkers aged 18 - 74 years in 1974 - 1980 and followed up for an average of 20.84 years. Totally 302 fatal CVD events were documented by the year of 2001. Cox proportional hazards regression models were undertaken to adjust for baseline variables with fatal CVD events as the outcome variable. Additive interaction model was used to evaluate the interaction between elevated TC and hypertension.

RESULTSHypercholesterolemia and hypertension were significantly associated with an increased hazard ratio (HR) of fatal CVD (1.67 (95%CI 1.18 - 2.38) and 2.91 (95%CI 2.23 - 3.80) respectively. Compared to participants with normotension and TC < 240 mg/dl, the HRs were 1.11 (95%CI 0.56 - 2.21), 2.74 (95%CI 2.07 - 3.64) for hypercholesterolemia and hypertension respectively, and 5.51 (95%CI 3.58 - 8.46) for participants with both risk factors. There was an additive interaction with a 2.65 (95%CI 0.45 - 4.85) relative excess risk (RERI) between hypercholesterolemia and hypertension on CVD.

CONCLUSIONWe found that the risk of fatal CVD was significantly associated with an additive interaction due to hypercholesterolemia and hypertension besides a conventional main effect derived from either of them, which highlights that the prevention and treatment of both risk factors might improve the individual risk profile thus reduce the CVD mortality.

Adolescent ; Adult ; Aged ; Asian Continental Ancestry Group ; Cardiovascular Diseases ; blood ; etiology ; mortality ; Cholesterol ; blood ; Humans ; Hypercholesterolemia ; blood ; complications ; Hypertension ; blood ; complications ; Male ; Middle Aged ; Steel ; Young Adult

BACKGROUNDThe association between increased serum uric acid (SUA) levels and cardiovascular risk has been debated for decades. Several large studies have provided conflicting results regarding the clinical significance of elevated SUA levels in cardiovascular disease (CVD) or cerebrovascular disease. The aim of this study was to investigate the relationship between SUA and CVD and all-cause mortality and their potential diagnostic value.

METHODSA total of 3570 in-patients ranging in age from 56 to 95 years (mean (67.36 +/- 11.36) years) were selected from 20 hospitals in Beijing and Shanghai. A carefully designed questionnaire was used to gather baseline data of each patient. All patients were divided into two main groups according to their SUA levels: high SUA and normal SUA groups. Serum indices and other important parameters were measured.

RESULTSCompared with normal SUA group, high SUA group had significant difference in systolic blood pressure (SBP), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), body mass index (BMI), and age (P < 0.05 or P < 0.01). High SUA prevailed in female and patients with history of essential hypertension, while history of smoking and diabetes showed no significant difference between two groups. All-cause and CVD mortality occurred more frequently in high SUA group than in normal SUA group. In the accumulative survival analysis, high SUA group had lower survival rate than normal SUA group both in CVD and all-cause mortality. COX regression analysis indicated that the history of smoking, age and high SUA were independent risk factors for the development of CVD.

CONCLUSIONSThese preliminary observations suggest that patients with high SUA levels would face higher risk of mortality. SUA measurement may be applied as a routine predictor for clinical assessment.

Aged ; Aged, 80 and over ; Asian Continental Ancestry Group ; Cardiovascular Diseases ; blood ; etiology ; mortality ; Female ; Humans ; Male ; Middle Aged ; Risk Factors ; Uric Acid ; blood

OBJECTIVES: Diabetes and obesity each increases mortality, but recent papers have shown that lean Asian persons were at greater risk for mortality than were obese persons. The objective of this study is to determine whether an interaction exists between body mass index (BMI) and diabetes, which can modify the risk of death by cardiovascular disease (CVD). METHODS: Subjects who were over 20 years of age, and who had information regarding BMI, past history of diabetes, and fasting blood glucose levels (n=16 048), were selected from the Korea Multi-center Cancer Cohort study participants. By 2008, a total of 1290 participants had died; 251 and 155 had died of CVD and stroke, respectively. The hazard for deaths was calculated with hazard ratio (HR) and 95% confidence interval (95% CI) by Cox proportional hazard model. RESULTS: Compared with the normal population, patients with diabetes were at higher risk for CVD and stroke deaths (HR, 1.84; 95% CI, 1.33 to 2.56; HR, 1.82; 95% CI, 1.20 to 2.76; respectively). Relative to subjects with no diabetes and normal BMI (21 to 22.9 kg/m2), lean subjects with diabetes (BMI <21 kg/m2) had a greater risk for CVD and stroke deaths (HR, 2.83; 95% CI, 1.57 to 5.09; HR, 3.27; 95% CI, 1.58 to 6.76; respectively), while obese subjects with diabetes (BMI > or =25 kg/m2) had no increased death risk (p-interaction <0.05). This pattern was consistent in sub-populations with no incidence of hypertension. CONCLUSIONS: This study suggests that diabetes in lean people is more critical to CVD deaths than it is in obese people.
Aged ; Blood Glucose/analysis ; *Body Mass Index ; Cardiovascular Diseases/etiology/*mortality ; Cohort Studies ; Diabetes Complications ; Diabetes Mellitus/*pathology ; Female ; Humans ; Male ; Middle Aged ; Proportional Hazards Models ; Risk Factors ; Stroke/etiology/mortality

OBJECTIVETo analyze the impact of hypertensive left ventricular hypertrophy (LVH) on cardiovascular events (CVD) in adult Beijing residents.

METHODSCVD risk factor survey was conducted in 7023 Beijing residents aged 25 - 64 by a stratified-random sample design from 1984 to 1993 in three years interval. CVD events were followed up and the association of the hypertensive LVH and risk of CVD and total death was analyzed by multivariable Cox Regression Model. All subjects were followed up to December 2004.

RESULTSThere were 211 non hypertensive LVH patients in the cohort and were excluded from the study. (1) There were 2240 hypertensive patients among 6812 subjects on baseline. The total prevalence of LVH was 11.8% (16.1% in male and 7.5% in female). (2) Compared to the group with normal blood pressure and without left ventricular hypertrophy, subjects with hypertensive LVH had significantly higher risk for acute coronary, acute stroke, total CVD and total death rate. The relative risks (RR) were 4.92 (95% CI: 2.3, 10.7), 4.2 (95% CI: 2.6, 7.0), 4.1 (95% CI: 2.6, 6.3) and 3.3 (95% CI: 2.0, 5.3), respectively. (3) Compared to the group with hypertension and without LVH, the group with hypertensive LVH had also significantly higher risk for acute stroke, total CVD and total death rate. The RR were 1.8 (95% CI: 1.1, 2.8), 1.7 (95% CI: 1.2, 2.3) and 1.7 (95% CI: 1.1, 2.7), respectively. (4) The population attribute risks (PAR) of hypertensive LVH to the incidents of acute CHD, acute stroke, total CVD and total death were 13.0%, 11.0%, 10.4% and 7.9%, respectively.

CONCLUSIONSHypertensive left ventricular hypertrophy was an independent risk factor for long term risk of cardiovascular events and death.

Adult ; Cardiovascular Diseases ; epidemiology ; etiology ; mortality ; Cause of Death ; China ; epidemiology ; Female ; Follow-Up Studies ; Humans ; Hypertension ; complications ; epidemiology ; Hypertrophy, Left Ventricular ; epidemiology ; etiology ; mortality ; Male ; Middle Aged ; Prospective Studies ; Risk Assessment ; Sampling Studies

OBJECTIVETo verify the optimal cut-off points for overweight and obesity in Chinese adults based on the relationship of baseline body mass index (BMI) to all-cause mortality, and incidence of cardiovascular diseases from pooled data of Chinese cohorts.

METHODSThe prospective study data of existing cohort studies in China were collected, and the age-adjusted all-cause mortality stratified by BMI were estimated. The similar analysis was repeated after excluding deaths within the first three years of follow-up and after excluding smokers. The incidence of age-adjusted coronary heart disease (CHD) and stroke stratified by BMI were also analyzed. Multiple Cox regression coefficients of BMI for the incidence of CHD and stroke after controlling other risk factors were pooled utilizing the methods of weighting by inverse of variance to reveal whether BMI had independent effect and its strength on the incidence of CHD and stroke.

RESULTSThe data of 4 cohorts including 76,227 persons, with 745,346 person-years of follow-up were collected and analyzed. The age-adjusted all-cause mortality stratified by BMI showed a U-shaped curve, even after excluding deaths within the first three years of follow-up and excluding smokers. Age-adjusted all-cause mortality increased when BMI was lower than 18.5 and higher than 28. The incidence of CHD and stroke, especially ishemic stroke increased with increasing BMI, this was consistent with parallel increasing of risk factors. Cox regression analysis showed that BMI was an independent risk factor for both CHD and stroke. Each amount of 2 kg/m2 increase in baseline BMI might cause 15.4%, 6.1% and 18.8% increase in relative risk of CHD, total stroke and ischemic stroke. Reduction of BMI to under 24 might prevent the incidence of CHD by 11% and that of stroke by 15% for men, and 22% of both diseases for women.

CONCLUSIONBMI < or = 18.5, 24-27.9 and > or = 28 (kg/m2) is the appropriate cut-off points for underweight, overweight and obesity in Chinese adults.

Adult ; Aged ; Body Mass Index ; Cardiovascular Diseases ; epidemiology ; etiology ; mortality ; Cause of Death ; China ; epidemiology ; Cohort Studies ; Female ; Humans ; Male ; Middle Aged ; Obesity ; complications ; Prospective Studies ; Reference Values ; Smoking ; adverse effects ; Stroke ; epidemiology ; etiology ; mortality

PURPOSE: Reduced heart rate variability significantly increases cardiovascular mortality. Metabolic syndrome increases the cardiac autonomic dysfunction. Recently, increasing cardiovascular mortality has been reported in patients with schizophrenia. This study was done to compare heart rate variability between adults with and without schizophrenia and to compare the relationship of heart rate variability to metabolic syndrome in hospitalized patients with schizophrenia. METHODS: This was a descriptive and correlational study in which 719 adults without schizophrenia and 308 adults with schizophrenia took part between May and June 2008. We measured the following: five-minute heart rate variability; high-frequency, low-frequency, the ratio of low-frequency to high-frequency, and the Standard Deviation of all the normal RR intervals. Data was also collected on metabolic syndrome, abdominal obesity, triglycerides, HDL cholesterol, blood pressure and fasting glucose. RESULTS: The Standard Deviation of all the normal RR intervals values of heart rate variability indices were 1.53+/-0.18. The low-frequency and high-frequency values of heart rate variability indices were significantly higher in hospitalized patients with schizophrenia (3.89+/-1.36; 3.80+/-1.20) than those in the healthy participants (2.20+/-0.46; 2.10+/-0.46). There were no significant differences between the schizophrenic patients with and without metabolic syndrome. CONCLUSION: The results of this study indicate that schizophrenia patients have significantly lower cardiac autonomic control, but they have significantly higher low-frequency and high-frequency values than those of healthy adults. Use of antipsychotic drug may affect the autonomic nervous system in schizophrenic patients. Metabolic syndrome was not associated with cardiac autonomic control in schizophrenia patients.
Adult ; Autonomic Nervous System/physiopathology ; Blood Glucose/analysis ; Blood Pressure ; Cardiovascular Diseases/complications/diagnosis/mortality ; Cholesterol, HDL/blood ; Female ; *Heart Rate ; Hospitalization ; Humans ; Male ; Metabolic Syndrome X/*complications/*physiopathology ; Middle Aged ; Obesity/etiology ; Schizophrenia/*complications/mortality/*physiopathology ; Triglycerides/blood