Prevalence of hypertension in bus drivers

This paper reports the results of a cross-sectional study conducted to evaluate the prevalence of hypertension in 1500 black and white male bus drivers from a large urban transit system in the US. Data for this study were compiled from the files of an occupational health clinic which conducts biennial medical examinations for drivers' license renewal. To test whether prevalence of hypertension was higher among bus drivers than among employed individuals in general, drivers were compared to three groups: individuals from both a national and local health survey and individuals undergoing baseline health examinations prior to employment as bus drivers. After adjustment for age and race, hypertension rates for bus drivers were significantly greater than rates for each of the three comparison groups. These findings support previous results from international studies of bus drivers suggesting that exposure to the occupation of driving a bus may carry increased health risk. This research has expanded into an on-going study which has the goals of clarifying the extent of hypertension in bus drivers and identifying specific behavioural and occupational factors that may be responsible for increased risk of cardiovascular disease.     

Job strain and pregnancy-induced hypertension.

In a case-control study we assessed whether exposure to high job strain during the first 20 weeks of pregnancy increases the risk of preeclampsia and gestational hypertension. Cases (128 with preeclampsia and 201 with gestational hypertension) and controls (N = 401) were primiparous women who had a paid occupation for at least 1 week during the first 20 weeks of their pregnancy and who delivered between 1984 and 1986 in 10 hospitals of Quebec, Canada. Based on their job title, we assigned women scores of psychological demand and decision latitude derived from the National Population Health Survey and classified these women as exposed to high (high demand, low latitude) versus low (low demand, high latitude) job strain. Women exposed to high job strain were more likely to develop preeclampsia [adjusted odds ratio (aOR) = 2.1; 95% confidence interval (CI) = 1.1-4.1] than women exposed to low job strain. The risk was quite similar for women exposed to a full-time, high strain job (> or =35 hours per week) (aOR = 2.0) than in a part-time, high strain job (aOR = 1.8). High job strain increased the risk of gestational hypertension slightly (aOR = 1.3; 95% CI = 0.8-2.2). These results indicate that women exposed to high job strain are at higher risk of developing preeclampsia and, to a lesser extent, gestational hypertension.     

Are race differences in the prevalence of hypertension explained by body mass and fat distribution? A survey in a biracial population.

Body mass and body fat distribution are important considerations in the study of hypertension. However, few studies have investigated the relationships with regards to race differences in elevated arterial pressure. A population-based sample of black and white adults was assessed by interview and physical measurement. The prevalence of hypertension (defined as 140/90 mmHg and/or medically treated) was disproportionately higher among blacks than whites. In addition, blacks had a higher prevalence of the more severe hypertension (160/95 mmHg) and hypertension with higher prevalence at earlier ages than whites. Black females had a significantly higher distribution of body mass index (BMI) than white females, while no difference was found in the distributions of males. White males had a higher distribution of waist to hip ratio (WHR) than black males, while black females had the higher values compared to white females. The prevalence of hypertension increased with BMI and WHR. Blacks maintained higher rates of hypertension after controlling for BMI and WHR, however, the margin of difference diminished when BMI and WHR was considered together. The black-white difference in hypertension was not completely explained by BMI and WHR. In addition, the strength of the association of hypertension and body size was different for blacks and whites which suggests possible differences in the mechanisms regulating blood pressure.     

Cancer incidence among urban bus drivers in Denmark

Summary During the period from 1978–1984 the incidence of cancer among 2465 male urban bus drivers in three major cities in Denmark was studied. The information with regard to cancer diagnosis was obtained from the Danish Cancer Registry. Danish men in 1981 were used as reference. Standardized Morbidity Ratio (SMR) for bladder- and skin cancer was significantly elevated among the bus drivers with values of 206 and 202, respectively. As to other cancers, no significant deviations from the expected were found. The same result was found when only drivers with more than ten years' seniority were included in the calculations. The incidence of skin cancer remained significantly elevated when corrected for degree of urbanization. Traffic density and whether the drivers worked in Copenhagen or in the province were not related to cancer incidence.     

Peptic ulcer among urban bus drivers in Denmark

As part of a survey on the work environment of bus drivers, 2045 (83%) of 2465 male bus drivers in the three major cities in Denmark in 1978 answered a postal questionnaire on health and working conditions. In order to evaluate the relative occurrence of peptic ulcer among the bus drivers, a follow-up study was also conducted. All hospital discharges with a peptic ulcer diagnosis among the bus drivers were registered from the Danish National Patient Register. All Danish men were used as reference group. On the basis of the 1978-questionnaire association between occupational and psychosocial factors and subsequent hospital discharge with a peptic ulcer diagnosis was studied. The prevalence of abdominal pain alleviated by food intake was 12% among bus drivers and 6% in the reference group. The incidence of hospital discharge with duodenal ulcer among younger bus drivers was twice the incidence among Danish men in the same age group. The incidence of all manifestations of peptic ulcer disease among bus drivers did not differ from the incidence among Danish men. Of occupational and psycho-social factors, wage dissatisfaction and smoking showed statistically significant association with hospital discharge with PU in a 6 3/4-year period. Job dissatisfaction, stress symptoms and lack of some social network factors tended to increase the risk of hospital discharge with PU.     

Coronary heart disease risk factors in urban bus drivers

The purpose of this study was to determine the risk factors for coronary heart disease (CHD) in 2297 bus drivers and skilled workers from the Taipei Municipal Bus Administrative Bureau. Data for this study were compiled from the medical records of annual physical examinations for bus drivers and skilled workers conducted at Taipei Municipal Chronic Disease Hospital during the period from July 1998 to June 1999. The results showed that, after adjustment for age, hypertension rates for bus drivers (56.0%, 986/1361) were significantly greater than for skilled workers (30.6%, 164/536). All age groups demonstrated a similar difference. Significant differences were also noted in body mass index, serum cholesterol, serum triglyceride and ischemic heart disease between bus drivers and skilled workers. Among bus drivers, the prevalence of obesity was 9.6%, hypercholesterolemia 34.0%, hypertriglyceridemia 69.4% and ischemic heart disease 1.7%. By contrast, among skilled workers, the prevalence of obesity was only 4.6%, hypercholesterolemia 29.9%, hypertriglyceridemia 30.6% and ischemic heart disease 0.9%. These findings suggest that exposure to the occupation of driving a bus may carry an increased risk of CHD and that drivers who develop signs of cardiovascular illness should be transferred to non-driving occupations within the company.     

Low back trouble among urban bus drivers in Denmark

The occurrence of low back trouble and possible connection with psychosocial conditions among urban bus drivers were studied using a questionnaire and subsequent registration of hospital discharges. 2,045 (83%) full-time male bus drivers in the three largest cities in Denmark answered a questionnaire in 1978 regarding psychosocial factors and health. The prevalence of frequent low back pain was 57%. In a control group of 195 motormen the prevalence was 40%. Standardized Morbidity Ratio for bus drivers discharged from hospital during the period 1978-1984 with the diagnosis lumbar disc herniation was 137 compared to all Danish men. These differences were statistically significant. Of psychosocial factors only "the feeling of being mentally unbalanced" was found to be statistically significantly related to subsequent hospital discharge with a LBT-diagnosis. Long seniority as bus driver of those discharged from hospital with LBT makes it probable that LBT has etiologic factors in the work environment. The sedentary position and whole-body vibrations may be contributory causes.     

Cancer incidence in urban bus drivers and tramway employees: a retrospective cohort study

OBJECTIVE: To investigate the risk of cancer associated with exposure to air pollution among bus drivers and tramway employees. METHODS: A retrospective cohort study of 18,174 bus drivers or tramway employees in Copenhagen in the period 1900-94. Data on employment were obtained from company files. Information on cancer was obtained from the Danish Cancer Registry. RESULTS: Findings showed that bus drivers or tramway employees had an increased risk of all malignant neoplasms (standardised incidence ratio (SIR) 1.24, 95% confidence interval (95% CI) 1.19 to 1.30). The relative risk was significantly increased for both men and women (SIR 1.24, 95% CI 1.19 to 1.30 and 1.28, 1.06 to 1.53, respectively). People employed for < 3 months had no increased risk of cancer (1.04, 0.81 to 1.31). For men who were employed for > 3 months the risk of lung cancer (1.6, 1.5 to 1.8), laryngeal cancer (1.4, 1.0 to 1.9), kidney cancer (1.6, 1.3 to 2.0), bladder cancer (1.4, 1.2 to 1.6), skin cancer (1.1, 1.0 to 1.2), pharyngeal cancer (1.9, 1.2 to 2.8), rectal cancer (1.2, 1.0 to 1.5) and liver cancer (1.6, 1.2 to 2.2) was significantly increased. For women employed for > 3 months the risk of lung cancer was significantly increased (2.6, 1.5 to 4.3). CONCLUSION: This cohort study shows that bus drivers and tramway employees are at an increased risk of developing several types of cancer. This might be due to the exposure to air pollution during working hours or to other risk factors, primarily smoking.     

Definition and prevalence of sedentarism in an urban population.

OBJECTIVES: The present study sought to formulate a precise definition of sedentarism and to identify activities performed by active people that could serve as effective preventive goals. METHODS: A population-based sample of 919 residents of Geneva, Switzerland, aged 35 to 74 years, completed a 24-hour recall. Sedentary people were defined as those expending less than 10% of their daily energy in the performance of moderate- and high-intensity activities (at least 4 times the basal metabolism rate). RESULTS: The rates of sedentarism were 79.5% in men and 87.2% in women. Among sedentary and active men, average daily energy expenditures were 2600 kcal (95% confidence interval [CI] = 2552, 2648) and 3226 kcal (95% CI = 3110, 3346), respectively; the corresponding averages for women were 2092 kcal (95% CI = 2064, 2120) and 2356 kcal (95% CI = 2274, 2440). The main moderate- and high-intensity activities among active people were sports (tennis, gymnastics, skiing), walking, climbing stairs, gardening, and (for men only) occupational activities. CONCLUSIONS: The definition of sedentarism outlined in this article can be reproduced in other populations, allows comparisons across studies, and provides preventive guidelines in that the activities most frequently performed by active people are the ones most likely to be adopted by their sedentary peers.     

Predictors of nursing home admission in a biracial population.

Racial differences in predictors of institutionalization were studied in a biracial North Carolina cohort (n = 4074). During 3 years of follow-up, 8.5% of Whites and 6.4% of African Americans were admitted to nursing homes. African Americans were one half as likely as Whites to be institutionalized after adjustment for other risk factors. Among Whites, impaired activities of daily living and cognition were the strongest predictors; among African Americans, impaired instrumental activities of daily living and prior history of nursing home use were strongest. Racial differences in nursing home use were not explained by financial and social support or physical and cognitive impairment.     

An inter-racial study of the prevalence of hypertension in an urban South African population

This study was done to compare and contrast the prevalence of hypertension in the three racial groups of Durban, namely the Africans (Zulus), Indians and Whites, and was a random house-to-house study of 1,000 of each group. The prevalence of hypertension according to World Health Organization (WHO) criteria was highest in the African (25%), intermediate in the White (22·8%) and lowest in the Indian (19%). Age-corrected prevalence rates were: African 25%, Whites 17·2% and Indians 14·19%. Prevalence of hypertension was more common in females than in males in the African and Indian population, unlike the Whites. In all racial groups the mean arterial pressure rose with age. Unlike the White study, African females between the ages of 35 and 40 years had a higher prevalence than males. There was an association between hypertension and diabetes mellitus in the Indian population. This study showed that all three population groups had hypertension which was undiagnosed, undetected or inadequately treated. The high prevalence of hypertension in the White and Indian population could explain the high incidence of ischaemic heart disease (IHD) in South Africa. In the African population, whilst they are spared IHD, hypertension is a major factor for the high incidence of cerebrovascular episodes. The lower prevalence of hypertension in the rural Zulu population and the difference in the years of residence between the hypertensive and normotensive urban Zulu suggests that urbanization plays an important part in the aetiology of hypertension in the Zulu.     

Menopausal hormones and breast cancer in a biracial population

OBJECTIVES: This study examined the association between menopausal hormones and breast cancer in a biracial population. METHODS: Logistic regression was used to calculate odds ratios for breast cancer associated with hormone use among 397 cases and 425 controls, all menopausal women. RESULTS: Odds ratios for ever use of hormones were 0.8 (95% confidence interval [CI] = 0.5, 1.2) for White women and 0.7 (95% CI = 0.4, 1.2) for Black women. Risk was not increased with longer duration of use or more recent use. CONCLUSIONS: Breast cancer risk was not increased among White or Black women who used menopausal hormones, despite patterns of use varying considerably between races.     

Temporal trends in gonococcal population genetics in a high prevalence urban community.

Molecular evolutionary studies can provide insights into the spread of infectious diseases and inform infection control measures. We performed a population genetic analysis of gonococcal isolates obtained over a 15-year interval in Baltimore, MD, where gonorrhea is highly prevalent. Categorical analysis of genetic differentiation revealed temporal structuring of the gonococcal population. The use of a new method to determine the historical demography of Neisseria gonorrhoeae from sequence data showed a strong correlation with trends in the number of reported cases of N. gonorrhoeae. The historical trends may also reflect the influence of social and demographic factors and the impact of antimicrobial resistance on the molecular epidemiology of gonorrhea in Baltimore over the past 2 decades. The strong correlation between the population genetic inferences over the last 20 years and the demographic data collected over the same time period demonstrates the utility of these approaches for the accurate inference of complex population dynamics using multilocus sequence data. The real time application of population genetic analysis can provide sentinel data on gonococcal prevalence, antibiotic resistance patterns and changing epidemiology of gonococcal infections.     

某公交车公司驾驶员与高血压发病关系的研究

目的研究公交车驾驶员高血压发病的关系。方法采用职业紧张因素量表(OSI),对150名公交车驾驶员进行职业紧张与高血压关系的人群调查。结果①高血压患者的OSI的得分为(187.5±15.3),非高血压者的OSI的得分为(156.5±12.3),经t检验,差异有显著性(P<0.01);②单因素分析结果显示,职业紧张与高血压有显著相关,RR值为2.17(P<0.05)。同时构成职业紧张的6个方面中有5个方面与高血压有关联(P<0.05);③多因素非条件Logistic回归分析结果显示,高血压除体重指数高、年龄、父母亲高血压病史进入回归方程外,职业紧张程度也进入回归方程。结论驾驶员高血压发病与其工作紧张有关。     

铁路机车司机高血压患病情况及危险因素分析

目的了解某铁路机车司机高血压患病情况及其主要危险因素。方法对1585名机车司机进行调查，包括病史询问、体格检查（包括血压、身高、体重）；40岁以上者，增加总胆固醇、三酰甘油及血糖测定。采用Excel2003和SPSS10．0软件进行单因素和多因素togistic回归分析。结果高血压患病率为51．86％。单因素分析：与高血压患病可能有关的危险因素有年龄、文化程度、吸烟、饮酒、体重指数（BMI）、总胆固醇、三酰甘油及血糖等；logistic回归分析：机车司机高血压主要影响因素有年龄、饮酒、BMI，其OR值依次为1．501、1．347和1．857；40岁以上人群高胆固醇血症、高三酰甘油血症及空腹血糖异常也是高血压危险因素。结论机车司机高血压患病率较高。降低BMI值和重视血脂、血糖异常的检测干预是预防高血压发病的重要环节。     

Mortality in a historical cohort of bus drivers

In an attempt to address previously reported excesses of ischaemic heart disease (IHD), lung cancer and bladder cancer among professional drivers, the mortality (SMR) of 2134 Montreal city bus drivers employed for at least five years as of January 1962 and followed until 31 December 1985 was compared with that of the male population of greater Montreal. The vital status of 94% of the cohort was ascertained. The number of deaths observed was 804. The overall mortality was somewhat lower than expected (SMR = 97). A small, non-significant excess mortality was found for ischaemic heart disease (IHD) (O/E = 313/295, SMR = 106, 95% CI: 95-118) and circulatory system diseases (O/E = 441/405, SMR = 109, 95% CI: 99-119). However, no excesses were observed for lung cancer (O/E = 78/84.4, SMR = 92, 95% CI: 73-114) or bladder cancer (O/E = 4/7.4, SMR = 54, 95% CI: 15-138). These results are compatible with other studies which have found a small risk of IHD for bus drivers.     

Increased prevalence of hypertension in a population exposed to aircraft noise

OBJECTIVES—To investigate whether there is a relation between residential exposure to aircraft noise and hypertension.
METHODS—The study population comprised two random samples of subjects aged 19-80 years, one including 266 residents in the vicinity of Stockholm Arlanda airport, and another comprising 2693 inhabitants in other parts of Stockholm county. The subjects were classified according to the time weighted equal energy and maximum aircraft noise levels at their residence. A questionnaire provided information on individual characteristics including history of hypertension.
RESULTS—The prevalence odds ratio for hypertension adjusted for age, sex, smoking, and education was 1.6 (95% confidence interval (95% CI) 1.0 to 2.5) among those with energy averaged aircraft noise levels exceeding 55 dBA, and 1.8 (95% CI 1.1 to 2.8) among those with maximum aircraft noise levels exceeding 72 dBA. An exposure-response relation was suggested for both exposure measures. The exposure to aircraft noise seemed particularly important for older subjects and for those not reporting impaired hearing ability.
CONCLUSIONS—Community exposure to aircraft noise may be associated with hypertension.