Study on the relationship between the age at natural menopause and postmenopausal metabolic syndrome / 中华预防医学杂志

To explore the relationship between the early or delayed age at natural menopause and metabolic syndrome (MS) in women. A total of 4 734 natural menopausal women who completed the baseline survey from November 2017 to January 2020 in the Guangzhou Middle-aged and Elderly Chronic Disease Prospective Cohort Study were selected in this cross-sectional study. Data on general demographic characteristics, disease history and female physiological health indicators were collected. Logistic regression model and restricted cubic spline curve were used to analyze the relationship between the age at natural menopause and MS. The results showed that the mean age of the subjects was (60±6) years old. The median (Q1,Q3) age at natural menopause was 50 (49, 52) years old, and the prevalence of MS was 14.8%(699/4 734). After adjusting for confounders, the age at natural menopause was closely related to MS in an approximate"U"shape. Compared with the group of normal age at natural menopause, the early age at menopause (OR=1.52, 95%CI: 1.12-2.06) and delayed age at menopause (OR=1.77, 95%CI: 1.36-2.30) had a higher risk of MS. In the group with time since menopause ≤6 years and 7-9 years, the risk of MS in the group with delayed age at menopause was 2.40 times (95%CI: 1.54-3.75) and 2.19 times (95%CI: 1.11-4.31) higher than that in the group with normal menopausal age, respectively. In conclusion, the early and delayed age at natural menopause increased the risk of MS. The increased risk of MS in delayed age at natural menopause mainly occurred within 10 years since menopause.

A study on the relationship between hearing impairment and blood pressure and hypertension in workers occupationally exposed to noise / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the correlation between noise and blood pressure and/or hypertension, and its age characteristic.</p><p><b>METHODS</b>The pure tone audiometric and blood pressure examinations were performed in 14537 workers from 157 factories. Hearing impairment was used as a surrogate indicator of cumulated noise exposure. The associations of hearing impairment and duration of noise exposure with blood pressure and hypertension were analyzed respectively after age and gender stratification.</p><p><b>RESULTS</b>Most of the objects were males (81.2%), younger than 35 years old (77.8%), and the duration of exposure to noise was less than 5 years (73.6%). The prevalence of hearing impairment in males was significantly higher than that in males, and increased with age and duration of noise exposure. Only in males with age younger than 35 years old, the systolic and diastolic blood pressures of subjects with sensorineural hearing loss significantly enhanced, and the diastolic blood pressure and prevalence of hypertension increased with duration of noise exposure. The risk of hypertension in males with sensorineural hearing loss significantly increased, the odds ratios in subjects with age younger than 35 years old and with age older than 35 years old were 3.0 (95%CI: 1.5 ∼ 6.1) and 2.1 (95%CI: 1.2 ∼ 3.4), respectively.</p><p><b>CONCLUSION</b>The severe hearing impairment induced by noise was associated with hypertension. It is suggested that people should pay attention to the effects of noise on hypertension in young workers.</p>

A cross-sectional study on the industrial noise over-limit status in Guangzhou factories / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the industrial noise over-limit status of the worksites in Guangzhou factories, so as to promote the prevention and control of occupational noise hazards.</p><p><b>METHODS</b>211 factories in Guangzhou were monitored and investigated. The analysis and assessment were developed for the properties and size of the factories, the districts of the factories being located, the industries of the factories being classified and the date of monitoring.</p><p><b>RESULTS</b>In this understudied factories, most of them were national-owned and joint-ventures, medium size, located in urban, and mainly involved in the industries of manufacturing of motor vehicle, shipping, electron and electric equipment, and the industries of petroleum and chemicals. The prevalence of noise over-limit was higher in joint-ventures (36.0%) and private-run enterprises (31.2%). The over-limit status mainly presented in industries of textile, food and beverage processing, and leather producing, with getting prevalence of over-limit 46.7%, 43.1% and 41.3% respectively. Subsequence were industries of manufacturing of electron and electric equipment, motor vehicle and shipping, and industries of printing and goods producing for culture and sports, with the prevalence for all > 35%. Factories monitored during spring and summer also had higher prevalence of noise over-limit. The similar results were got after adjustment for each other using multivariable regression. The most common over-limit sites mainly focused on the operation of cutting and sawing, milling and planing, pressing, riveting, drilling, jointing, assembling and quality inspecting in industries of mechanism processing and manufacturing, on quality inspecting and packing in industries of pharmacy and food and beverage manufacture, on spinning and scutching in textile industry, and on cleaning and maintaining as assistant jobs, and patrolling and inspecting air-press machine, ventilation machine, dynamotor and pump.</p><p><b>CONCLUSION</b>Noise in Guangzhou factories widely exists with different industries and districts. To strengthen noise occupational hazards prevention and control for the high risk districts, industries and worksites should be the key job in the future.</p>

Association between anthropometric indices of obesity and cognition ability in middle and elderly population / 中华神经医学杂志

Objective To explore the association of mild cognitive impairment (MCI) with obesity level in middle and elderly population. Methods A total of 19181 subjects aged 50-85 years were collected in this study from the first and second recruitment phase of the Guangzhou Biobank Cohort Study. The subjects received face-to-face interviews to collect the detailed information on their sociodemographic background, occupational exposures, living environment, lifestyle, family and personal disease histories, and had physical examinations and tests including 12-lead ECG, chest radiograph, and pulmonary function testing. Each subject was screened for a range of fasting biochemical parameters. The cognitive ability was tested with 10-words delayed memory test. The associations between cognition function and anthropometric indices of obesity, including body mass index, waist-to-hip ratio (WHR) and waistline, were evaluated. Results Apart from fast glucose and hypertension in subjects with normal cognition function and abnormal cognition function, some lifestyle and such physiological and biochemical factors as age, education, smoking status, and drinking status were significantly different in both gender (P＜0.05). WHR was the independent risk factor of MCI in both gender (P＜0.05). Logistic regression indicated that high WHR was a risk of MCI in both gender; the greater the WHR, the poorer memory the middle and elderly population; the OR and 95％ CI was 1.57 (1.42-1.72) in female and 1.22(1.05-1.41) in male. Conclusion Centripetal obesity is associated with MCI. WHR is a sensitive indicator influencing the cognitive function in women.

Polymorphisms of vascular diseases-related genes in Guangzhou Biobank Cohort Study / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the polymorphisms of cerebrovascular and cardiovascular disease genes using Taqman single nucleotide polymorphism (SNP) genotyping kits.</p><p><b>METHODS</b>A total of 2000 subjects were recruited from the Guangzhou Biobank Cohort Study (GBCS), and 15 SNPs were detected using Taqman SNP genotyping kits and an ABI 7900HT real time PCR system. The data were tested for the Hardy-Weinberg equilibrium, and then compared with the data of the Chinese population from the International HapMap Project (HapMap_HCN).</p><p><b>RESULTS</b>(1) All genotype data of the 15 SNPs were consistent with the Hardy-Weinberg rules. (2) The significant differences were observed among two SNPs, rs4220 and rs5368 and the HapMap_HCN (rs4220 28.2% vs 17.8%; chi(2) = 4.891, P = 0.028; rs5368 22.1% vs 32.2%, chi(2) = 5.137, P = 0.024). Comparing other gene bank data, such as AFD-CHN-PANEL, the Allele Frequency Database (ALFRED) and JBIC-allele, it would be most likely that our observations represent differences between the Northern and Southern populations in China.</p><p><b>CONCLUSION</b>Such Biobank study provided a useful platform for the study of the role of genetic and environmental determinants on cerebrovascular and cardiovascular disease.</p>

Dose-response relationship between smoking status and carotid atherosclerosis / 中华流行病学杂志

Objective To examine the dose-response relationship of smoking status with carotid atherosclerosis in 959 relatively healthy Chinese men. Methods 959 older Chinese men were selected from Guangzhou Biobank Cohort Study (GBCS) on cardiovascular disease. Personal histories were collected and fasting plasma glucose and lipids, blood pressure, and common carotid artery intima-median thickness (CCA-IMT) were measured. Results ( 1 ) Composition of the cases:39.1% were non-smokers, 25.7% were former smokers and 35.2% were current smokers. The mean (95% confidence interval) carotid IMT was 0.78 (0.77-0.79) mm. 18.4% of the subjects had carotid IMT equal to or thicker than 1.0 mm while 34.1% had carotid plaque. (2)After adjusting for age, sex,physical activity, body mass index, fasting glucose, triglyceride, high-density lipoprotein cholesterol,systolic and diastolic blood pressure, compared to never smokers, current smokers had significantly increased risk for thicker IMT and carotid plaque [odds ratio (OR) = 1.82, 95% GI: 1.30-2.55 and OR=1.95, 95%CI: 1.38-2.75, respectively, all P＜0.001]. The risk for thicker IMT and carotid plaque increased with the increasing amount (cigarettes/day) and duration of smoking (years) as well with cigarette pack-years (P for trend all ≤0.01 ). Conclusion An elevated risk with a clear doseresponse relationship was found between cigarette smoking and carotid atherosclerosis. Quitting smoking or reducing the amount of smoking may lower the risk of atherosclerosis, preventing and controlling the occurrence of cardiovascular diseases, and reducing the related cardiovascular mortalities.

Study on the association between gene polymorphism of ENPP1 and left ventricular hypertrophy: A Guangzhou Biobank Cohort Study-CVD / 中华流行病学杂志

Objective To examine the association between genetic polymorphism of rs1409181 in ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) and left ventricular hypertrophy (LVH) among older Chinese in Guangzhou. Methods 390 subjects aged ≥50 years were randomly selected from the Guangzhou Biobank Cohort Study-CVD. Information on personal history, blood pressure, fasting plasma glucose and lipids were collected. Color Doppler ultrasound was used to measure the indicators of LVH, including left ventricular internal diastolic diameter (LVIDD) , thickness of the interventricular septum diastolic wall (IVSD) and the posterior wall diastolic diameter (LVPWD). LVIDD was calculated using Devereux ventricular mass (LVM)equation while the Left ventricular mass index (LVMI) equation was used to estimate LVH. The genotype of rs1409181 was determined by Taqman SNP genotyping kits using the ABI 7900HT real time PCR system. Results In the GG, CG and CC genotype groups, the proportions of LVH were 21.5%, 28.2% and 37.5% respectively. Compared with GG, the adjusted odds ratios (95% confidence interval) for the LVH were 1.39(0.78-2.50) and 2.36(1.21-4.60) for CG genotype and CC genotype of ENPP1 respectively (P for trend=0.01). Conclusion Polymorphism of ENPP1 gene rs1409181 was associated with LVH in the older Chinese people in Guangzhou.

Effect of physical activity strength on the diabetes mellitus prevalence in the elderly under the in fleuce of International Physical Activity Questionnaire / 中华流行病学杂志

Objective To examine the impact of International Physical Activity Questionnaire (IPAQ) physical activity intensity on to the prevalence of diabetes mellitus among Chinese elderly. Methods A total number of 1996 residents aged 50 or above living in Guangzhou city were recruited from the phase 3 of the Guangzhou Biobank Cohort Study. Information on physical activity and fasting plasma glucose status was derived from standardized interviews and laboratory assays. Results Among the participants who were classified as physically active (60.0%), moderate active (29.8%) and inactive (10.2%), the prevalence rates of type 2 diabetes mellitus were 9.1%, 12.0%and 14.2%,respectively. After adjustment on age, sex, obesity and other potential confounding factors, data from logistic regression model showed that the odds ratios (95% confidence interval) for diabetes on subjects in physically moderate active and active group were 0.75 (0.46-1.26)and 0.60 (0.38-0.97) respectively with P for trend as 0.03, when comparing to those physically inactive ones. Conclusion Promotion of physical activity might have had some effects in reducing the risk of diabetes mellitus among the older adults.

Personality and occupation stress of workers in processing line in Guangzhou / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study relationships between personality and occupational stress of workers in processing line in Guangzhou.</p><p><b>METHODS</b>452 workers in processing line in Guangzhou were investigated by the Eysenck Personality Questionnaire (EPQ) and Occupational Stress Indicator (OSI).</p><p><b>RESULTS</b>N scores and P scores of EPQ were positively correlated with the occupational stress and the poor physical fitness status (r value was 0.196, 0.128, 0.202, 0.218, respectively) (P < 0.01). N scores of EPQ were positively correlated with the type A behavior (r = 0.164) and negatively correlated with the mental well-being level (r = -0.196, P < 0.01). P scores of EPQ were negative correlated with the sense of job satisfaction and the stress coping ability(r value was -0.146, -0.140, respectively) (P < 0.01). E scores and L scores of EPQ were negatively correlated with the type A behavior (r value was -0.159, -0.138, respectively) (P < 0.01). E scores of EPQ were positively correlated with the stress coping ability (r = 0.176, P < 0.01). L scores of EPQ were negatively correlated with the occupational stress, the poor physical fitness status and the explanation to vicinity event (r value was -0.139, -0.140, -0.111, respectively) (P < 0.01, P < 0.05).</p><p><b>CONCLUSION</b>The personality of neuroticism, psychoticism and introversion may be related to the occupational stress, the sense of job satisfaction and unhealthy mental reaction.</p>

Impact on calcification of aortic arch by lifestyle-related,physiologic and biochemical factors / 中华流行病学杂志

Objective To explore the impact of lifestyle-related,physiological and biochemical factors on aortic arch calcification(AAC).Methods 20 430 subjects aged 50 to 85 years were included in this study from the first and second recruitment phase of the Guangzhou Biobank Cohort Study.All the subjects received face-to-face interviews to collect detailed information on their socio-demographic background,occupational exposures,living environment,lifestyle,family and personal disease histories,and received a physical examination and tests including 12-lead ECG,chest radiograph,and pulmonary function testing.Each subject was screened for a range of fasting biochemical parameters.Radiographs were reviewed by two senior radiologists.300 radiographs were independently read by the two radiologists to assess agreement using Kappa coefficient.Logistic regression was used to assess the association between life style,physiological and biocheroical factors and AAC.Resuits (1)The rate of agreement on diagnosis for the two radiologists was 85% and Kappa coefficient was 0.68(P<0.01) which showed a moderate agreementbetween the two radiologists.(2) Except hypertension,the subjects were significantly difierent on their lifestyle,physiological and biochemical factors in both men and women(P<0.05).(3)AAC was significantly associated with older age,smoking status,LDL-C,and hypertension(P<0.01)in both genders.Ors(95%CI)indicated the following results:age was 1.11(1.10-1.12) in men and 1.12 (1.12-1.13)in women;smoking as 1.31(1.17-1.47)in men and 1.31(1.09-1.57)in women;LDL-Cas 1.16(1.06-1.27) in men and 1.38(1.22-1.56) in women,hypertension as 1.33(1.18-1.50) in men and 1.27(1.18-1.38) in women.However,diabetes was found to be associated with an increased risk of AAC in women[OR(95%CI)]1.38(1.22-1.56).Conclusion Age,smoking,hypertension and Low-density lipoprotcin level were risk factors to beth genders,on AAC,while diabetes increased the risk of AAC,in women.

A cross-sectional study on smoking behavior and nicotine dependence among workers in Guangzhou / 中华流行病学杂志

Objective To investigate smoking behavior and nicotine dependence (ND), so as to provide evidence for tobacco control in workers. Methods A cross-sectional study to investigate smoking behavior and ND in 668 workers with different job assignment in Guangzhou. Fagerstrom Test for Nicotine Dependence and logistic regression model were used to analyze the association between ND and some risk factors. Results (1) The prevalence of ever-smoking was 65.0 % ( 348/535 ) in men ( 55.5 % daily smokers, 5.4% occasional smokers and 4.1% ex-smokers), and 3.0% (4/133) in women. The prevalence of current smoking for manual workers and safety officers were 67.6 % and 64.5 % respectively.(2) Among daily and occasional smokers, 66.7% and 89.7% of them had low ND respectively. Among daily smokers, ND increased with the duration of smoking. Manual workers and officers had higher ND. Conclusion The prevalence of smoking was relatively high in workers and officers and in men. However,majority of the smokers were with low ND and could be the prioritized target for a primary smoking cessation intervention program.

A cross-sectional study on self-reported health and intention of quitting smoking of smokers in Guangzhou factory workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the health status and intention of quitting smoking in factory workers, so as to provide scientific evidence for smoking control.</p><p><b>METHODS</b>A cross-sectional survey was carried out on smoking behavior, self-reported health status (SRHS), and intention of quitting smoking in 668 Guangzhou factory workers with different job types. Fagerstrom Test for Nicotine Dependence (FTND) was used on current smokers. Logistic regression model was used to analyze the association of SRHS, difficulty of quitting smoking (DQS) with some risk factors.</p><p><b>RESULTS</b>(1) 65.0% (n = 348) male and 3.0% (n = 4) female workers were ever-smokers. 90.6% of male smokers usually smoked when getting together with friends or smokers, staying at home, or at leisure time, or just after a meal. (2) 10.7% of the daily smokers and ex-smokers had a worse SRHS than the general same-age people, which is significantly higher than 5.1% of the occasional smokers and those who were never smoking. The OR was 2.22 (95% CI 1.08 approximately 4.59) after adjusting age and education. (3) Of male daily smokers, 50.5% ever thought of quitting smoking. The proportions of ever-thought of quitting smoking were 73.3%, 50.0% and 37.2% respectively in those with better, pretty the same and worse SRHS than the general same-age people (P = 0.009). The proportions of DQS self-scored 30 or less, 31 to 60 and 60 or more were 26.9%, 24.9% and 48.2% respectively in male daily smokers. The OR for DQS (self-scored > 30 vs < or =30) increased with increasing number of colleague smoked and worked around, and with nicotine dependence.</p><p><b>CONCLUSION</b>Daily smokers and former smokers have worse SRHS than those who are occasional smokers or never smokers in male workers, and most of those with worse SRHS who ever thought of quitting smoking. The DQS is mainly significantly associated with number of colleague smoking and working around, and with nicotine dependence.</p>

Electrocardiogram change of workers after disengaging occupational noise exposure / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To examine electrocardiogram (ECG) change of workers after leaving occupational noise exposure.</p><p><b>METHODS</b>In the first phase of the Guangzhou Biobank Cohort Study, 10413 Guangzhou residents aged 50 years or more received a face-to face interview including noise exposure history, a full medical check-up and laboratory tests in 2003 - 4. ECG examination was carried out using 12-lead MAC-CS ECG machine made in HP Ltd, Shanghai, China. ECG of every subject was independently diagnosed by two doctors who had obtained ECG diagnosis qualification.</p><p><b>RESULTS</b>(1) Among 10413 subjects, 70% were female, and more than half were aged 60-69 years. The mean age and education level in males were higher than those in females. (2) 2119 subjects (21.0%) were previously exposed to noise and were retired now. (3) The prevalence of ECG abnormality was respectively 82.4% and 79.1% in females and males. Rate of ECG abnormality increased with age in both females and males (P = 0.000), and was lower in females with higher education level (P = 0.000). There was not significant difference in ECG abnormality between workers previously exposed or unexposed to noise in both females and males (P > 0.05). 4 Comparing workers previously exposed to those unexposed to noise in both females and males, after adjusting for age, educational level and smoking status, the rates of arrhythmia, axes deviation, atria and ventricle hypertrophy, ST-T change and coronary artery syndrome were not significantly different (P > 0.05).</p><p><b>CONCLUSION</b>Our study showed that the prevalence of ECG abnormality was not significantly increased in workers previously exposed to noise and had left exposure now compared to those never exposed to noise. Because our study was cross section and occupational history was obtained from a questionnaire but was not confirmed by the companies, further study is needed.</p>

Epidemiological application of ion chromatography for urinary iodine monitoring / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a method of ion chromatography for urine iodide determination and evaluate its application in epidemiological studies.</p><p><b>METHODS</b>Urinary iodine was determined using ICS-2500 ion chromatography coupled with IonPac AS7 analytical column (4 mm x 250 mm), silver electrode and direct current amperometry for 467 elderly subjects (above 50 years) with their urinary Tsh and FT4 also determined. The history of thyroid diseases was examined among these subjects.</p><p><b>RESULTS</b>The peak area of the ion chromatography was linearly correlated with urinary iodine concentration, with the correlation coefficient of 0.9999. The detection limit of iodide was around 3.5 microg/L (S/N=3), with coefficients of variation ranging from 3.16% to 3.45% and mean recovery rate of 95%. The urinary iodine level in the 467 elderly subjects showed a positively skewed distribution with the median level of 224.7 microg/L.</p><p><b>CONCLUSION</b>Ion chromatography for urinary iodine determination has excellent selectivity, sensitivity, reliability, accuracy and stability, and may ensure satisfactory effect for application in epidemiological studies.</p>

The prevalence and characteristics of aortic arch calcification among middle and elderly population in Guangzhou / 中华流行病学杂志

<p><b>OBJECTIVE</b>To examine the prevalence and characteristics of aortic arch calcification (AAC) in residents aged 50 or over in Guangzhou, China.</p><p><b>METHODS</b>Face-to-face interview, physical examination and laboratory tests were conducted on 10 413 Chinese adults aged 50 or over. Posterior-anterior plain chest X-ray radiographs were obtained from 10 305 subjects using a Toshiba KSO-15R machine. The radiographs were reviewed together by two radiologists while 300 radiographs were independently gone through by two radiologists to assess the agreement with Kappa coefficient method.</p><p><b>RESULTS</b>The rate of agreement on Diagnosis for the two radiologists was 85.0% and Kappa coefficient was 0.68, with P < 0.001 which showed a moderate agreement between the two radiologists. Among the 10 305 subjects, there were 3064 men and 7349 women, with their mean age (+/- standard deviation) as 64.0 +/- 6.0 and 66.2 +/- 5.8, respectively. Most of them had educational level of middle school or below, and most of their occupations were factory or agricultural workers. The prevalence of AAC was 40.6%. Women showed significantly higher prevalence rate than men (41.4% versus 38.6%, P < 0.001) and the prevalence of AAC increased significantly with age. Subjects with primary educational level or below had the highest prevalence of AAC. There was no significant association found between occupation and AAC prevalence. 98.7% of the subjects with AAC occurred in aortic arch. Most AAC had a length of 10 mm or longer and a width from 1-4 mm, which indicated the severity of AAC among the subjects.</p><p><b>CONCLUSION</b>The prevalence of AAC among Guangzhou Biobank Cohort was about 40.6%, higher than those reported in foreign studies, while most of the lesions were quite serious.</p>

A prospective cohort study on comparison of risk of death of respiratory system diseases between occupational dust exposure and smoking / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To compare the effects of dust exposure and smoking on mortality of respiratory system diseases (RSD).</p><p><b>METHODS</b>Based on the Guangzhou Occupational Health Surveillance Record System established between 1989 and 1992, 80,987 factory workers, aged 30 years old or older, occupationally exposed or not exposed to dusts, were included in a prospective cohort study.</p><p><b>RESULTS</b>(1) The mean age of the cohort was 43.5. Most subjects were workers, had secondary education, and almost all were married. The dust exposure rate was 16.3%, the smoking rate 43.7% and the alcohol-drinking rate 33.5%. (2) The cohort was followed up for 8 years on average, but 35 people (0.04%) were lost for follow up. Among the 1593 deaths, 219 and 90 people died of lung cancer and non-cancer respiratory system diseases (NCRSD) respectively. (3) The adjusted relative risk (RR) of death of lung cancer for smokers, 3.32, was 2.2 times of that for dust exposed workers, 1.53, and the RR of death of NCRSD for dust exposed workers, 2.41, 1.28 times of that for smokers, 1.89, especially for silica dust-exposed workers, 5.72, 3.03 times of that for smokers. Dust exposure combined with smoking caused significantly higher RR of death of RSD. (4) In male, the death risks of RSD were increased with the amount of smoking per day and years of smoking.</p><p><b>CONCLUSION</b>Occupational dust exposure and smoking may cause excessive lung cancer and NCRSD death with synergistic effects. Smoking has higher RR of Lung cancer death than dust exposure. However, the dust exposure contributes to higher RR of NCRSD death. There is a significant dose-effect relationship between smoking and the death risk of RSD.</p>

Determination of cotinine in human urine with gas chromatograph-mass spectrometry / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To establish the method of gas chromatograph-mass spectrometry (GC-MS) for the determination of the cotinine (COT) in human urine.</p><p><b>METHODS</b>The conjugated trans-3'-hydroxycotinine (THOC) and COT were hydrolyzed in human urine with beta-glucuronidase. The composition of COT was extracted with the mixture of dichloromethane and n-butyl acetate (2:1) and was separated with HP-5MS fused-silica capillary column. The GC-MS was used for determining its content.</p><p><b>RESULTS</b>The monitoring limit of this method was 0.02 microg/L. Its recovery rate was higher than 90%, Its accuracy rate was 4.30%. It was used for the determination of the cotinine in human urine in Guangzhou Biological Bank the Elderly Cohort.</p><p><b>CONCLUSION</b>The GC-MS method is a good microanalysis for monitoring the cotinine in human urine rapidly and accurately with little background disturbance. It has been applied in our Guangzhou Cohort Study for determining cotinine in human urine.</p>

Analysis of the situation of occupational health surveillance and the morbidity of occupational diseases in Guangzhou / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To analyze the situation of occupational health surveillance and the characteristics of occupational diseases in Guangzhou.</p><p><b>METHODS</b>The situation of occupational health surveillance and the morbidity of occupational diseases were studied retrospectively by use of the physical examination data collected from the labour hygienic reports of the city from 1993 to 2002. The data were divided into two groups: the first group from 1993 to 1997, and the second from 1998 to 2002.</p><p><b>RESULTS</b>Annual average of occupational health examination in the past 10 years was over 75%. The data in the second group (1998 - 2002) showed that the number of hearing loss observed subjects, noise surveilled personnels, dust and chemicals contraindicated personnels were significantly higher than those in the 1st group (P < 0.01). The morbidity of chronic occupational disease newly occurred was 91 cases in lst group, and 181 cases in 2nd group (P < 0.05), in which the incidence of chemical poisoning and noise induced hearing loss increased significantly but that of pneumoconiosis between two groups was not significantly different (P > 0.05). In the past 10 years, 581 cases of occupational diseases were diagnosed, of which, 309 cases (53.18%) were acute poisonings, while 272 cases (46.82%) were chronic occupational diseases. Pneumoconiosis, lead and benzene poisoning were common in chronic occupational diseases (16.70%, 16.87% respectively). With the passage of time, the incidence ages of pneumoconiosis, chemical poisoning and total occupational diseases tended towards younger. The difference was statistically significant (P < 0.01)</p><p><b>CONCLUSION</b>A normal system for occupational health surveillance has been developed in Guangzhou. Detectable rates in focused surveillance and contraindication have been obviously increasing. The incidence of occupational disease (mainly including acute occupational poisoning, pneumoconiosis, lead and benzene poisonings) is also going up. The incidence age of chronic occupational diseases tends to be younger accompanied with a shorter work history.</p>

A prospective cohort study on the comparison of risk of occupational dust exposure and smoking to death / 中华流行病学杂志

<p><b>OBJECTIVE</b>To compare the effects of dust exposure and smoking on mortality.</p><p><b>METHODS</b>Based on the Guangzhou Occupational Health Surveillance Record System established in 1989-1992, 80 987 factory workers, aged > or = 30, occupationally exposed to dust and non-exposure to dust, were included in a prospective cohort study.</p><p><b>RESULTS</b>(1) The mean age of the cohort was 43.5. Most subjects were workers, with secondary education, and married. Out of them 16.3% having ever exposed to dust, 43.7% ever smoked and 33.5% drank alcohol. (2) The cohort were traced for 8 years on average, but 35 were lost for follow-up. Malignant neoplasm was most commonly seen among 1539 deaths. (3) The adjusted relative risk (RRs) of death of all causes, malignant neoplasm and cerebro-cardiovascular diseases for dust exposed workers were close to those for smokers. However, the adjusted RRs of death of nasopharynx cancer and respiratory system diseases for dust exposed workers were higher than those for smokers. The adjusted RRs of death of lung cancer and stomach cancer for smokers were 2.2 times and 1.5 times of that for dust exposed workers respectively. Dust exposure combined with smoking caused significantly higher death RR. (4) In males, the adjusted RRs of death of all causes, malignant neoplasm and respiratory system diseases for silica dust exposed workers and the adjusted RR of death of cerebro-cardiovascular diseases for wood dust exposed workers were higher those in smokers. (5) The population attributable risk percentage (PARP) of all causes of death for smokers was 2.5 times of that for dust exposed workers. (6) In males, the risks of death for all causes, malignant neoplasm, lung cancer and stomach cancer increased with the amount of smoking per day and the duration of smoking. The risks of death caused by coronary heart disease and respiratory system diseases were increasing with the amount of smoking per day and the duration of smoking respectively.</p><p><b>CONCLUSIONS</b>The adjusted RRs for dust exposed workers were close to those for smokers with dust exposure and smoking having synergistic effects. Some of the adjusted RRs for smokers were higher than those for dust exposed workers PARP for smokers was higher than that for dust exposed workers. Our findings suggested that there was a significant dose-effect between smoking and risk of deaths.</p>

A cohort study on the relationship between blood pressure levels and the mortality of cerebro-cardiovascular diseases in Guangzhou workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the relative risk (RR) of mortalities of cerebro-cardiovascular diseases (CVD) in Guangzhou workers with hypertension.</p><p><b>METHOD</b>Prospective cohort study was conducted in 78,379 workers, aged >or= 35, from 399 factories. Cox regression model were mainly used for data analysis.</p><p><b>RESULTS</b>(1) There were 48,705 male and 29,674 female workers in the cohort. All workers were followed-up for 8 years. 363 CVD deaths (male 305, female 58) mainly died of stroke, coronary heart disease and hypertension. The crude mortalities were 78.58/100,000 person years in male and 24.55/100,000 person years in female. (2) Compared with the optimal or normal blood pressure (ONBP), the RR (95%) of CVD deaths with high blood pressure (HBP) were 6.19 (4.85 - 7.91) in male and 2.78 (1.59 - 4.85) in female. In male, compared with ONBP, the RR of CVD deaths without illness but with 1st-grade HBP at baseline, and of those suffered non-CVD but with 1st-grade HBP at baseline, and of those suffered CVD with 2nd-grade HBP at baseline were 3.98, 3.25 and 3.15 respectively (P < 0.01). (3) After stratifying of age, smoking, drinking, educational levels and occupational exposure, the RR of CVD deaths was higher in those who were younger, or ever-smoking, non-drinking, higher educational level, exposed to occupational hazards and with hypertension.</p><p><b>CONCLUSION</b>There is relationship between BP levels and CVD mortality. High BP may affect CVD deaths at younger age. Comprehensive measures should be used to reduce the risk of CVD deaths.</p>