In situ expression of ICAM-1 and its mRNA in the lung tissue of asthmatic rats

The objective of this work was to determine whether the prevalence of respiratory symptoms differed among workers exposed to different types of metal-working fluids. As part of a mandatory surveillance system for occupational illness, from 1988-1994, the Michigan Department of Public Health received, 86 occupational disease reports of work-related asthma secondary to exposure to metal-working fluids. As part of a public health program, follow-up industrial hygiene inspections, including medical interviews of the workforce, were performed at companies where the reported cases had become ill. Metal-working fluids were the second most common cause of work-related asthma reported in the state. Most of the reports were from the automobile industry. Follow-up inspections were conducted at 37 facilities where the individuals with work-related asthma had worked. Seven hundred and fifty-five workers at these facilities were interviewed. Only one facility was above the allowable oil mist standard. Despite the exposure levels being within the legal limits, approximately 20% of the fellow workers of the reported cases had daily or weekly respiratory symptoms suggestive of work-related asthma. Workers exposed to emulsified, semisynthetic, or synthetic machining coolants were more likely to have chronic bronchitis; to have visited a doctor for shortness of breath; to have visited a doctor for a sinus problem; to be bothered at work by nasal stuffiness, runny nose, or sore throat; and to have an increased prevalence of respiratory symptoms consistent with work-related asthma, compared to workers exposed to mineral oil metal-working fluids. These findings were found in individuals who currently smoked, had never smoked or were ex-cigarette smokers. Further research to determine the chemical components or microbial contaminants responsible for these findings is needed.     

Heparin, but not other proteoglycans potentiates the mitogenic effects of FGF-2 on mesencephalic precursor cells

Occupational asthma may account for a significant proportion of adult-onset asthma, but incidence estimates from surveillance of physician reports and workers' compensation data (0.9 to 15/100,000) are lower than expected from community-based cross-sectional studies of asthma patients. We conducted a prospective cohort study of 79,204 health maintenance organization members between the ages of 15 and 55 at risk for asthma. Computerized files, medical records, and telephone interviews were used to identify and characterize asthma cases. Evidence for asthma attributable to occupational exposure was determined from work-related symptoms and workplace exposure. The annual incidence of clinically significant, new-onset asthma was 1.3/1,000, and increased to 3.7/1,000 when cases with reactivation of previously quiescent asthma were included. Criteria for onset of clinically significant asthma attributable to occupational exposure were met by 21% (95% CI 12-32%) of cases giving an incidence of 71/100,000 (95% CI 43-111). Physicians documented asking about work-related symptoms in 15% of charts, and recorded suggestive symptoms in three cases, but did not obtain occupational medicine consultation, diagnose occupational asthma, report to the state surveillance program, or bill workers' compensation for any of them. These data suggest that the incidence of asthma attributable to occupational exposures is significantly higher than previously reported, and accounts for a sizable proportion of adult-onset asthma.     

Respiratory health and immunological profile of poultry workers

OBJECTIVES: To examine work-related respiratory symptoms in poultry workers, and to test for immunologically mediated responses to poultry-related agents. DESIGN: A cross-sectional survey of differentially exposed poultry workers and unexposed blue-collar workers. SETTING: Three poultry farms and a poultry plant in Gauteng (exposed workers) and a municipal workers' clinic in Johannesburg (controls). PARTICIPANTS: 134 poultry workers (85.4% of all eligible workers) and 122 controls (> 95% response rate). OUTCOME MEASURES: Respiratory symptoms plus allergy and hypersensitivity to poultry agents identified by skin-prick tests, and by the presence of specific IgE and IgG enzyme-linked immunoflow assay and nonspecific (radial immunodiffusion) antibodies. RESULTS: Smoking habits and atopic status were similar in the poultry workers and the controls. Symptoms were very common in poultry workers, for example work-related cough in 32% and work-related wheeze in 23% of highly exposed workers. Significantly more poultry workers than controls complained of chest symptoms (increasing with increasing exposure), and of eye, skin and nose irritation at work. More poultry workers than controls had symptoms consistent with asthma (e.g. 3%, 4%, 13% and 11% in controls and subjects with low, medium and high exposure, respectively), and symptom complexes associated with organic dust exposure. Five poultry workers had positive skin-prick test reactions to poultry-specific antigens, but none of the unexposed controls reacted. More poultry workers than controls had positive immunodiffusion test reactions to chicken feed, feathers and serum, and IgE to chicken faeces. There was no association between immunological status and respiratory symptoms. CONCLUSION: We found a very high prevalence of exposure-related symptoms in poultry workers; improved hazard control is strongly indicated. Tests of allergy and hypersensitivity were associated with exposure, but not with disease. The possibility of useful tests of sensitisation has not been excluded; a prospective study design is likely to be more rewarding than cross-sectional approaches such as in this study.     

Thoracic complications associated with utilization of the air turbine dental drill

BACKGROUND: The prevalence of asthma is rising and there are recent reports of increasing asthma rates among top level skiers and runners in the Nordic countries. METHODS: The lifetime occurrence of pulmonary diseases (asthma, chronic bronchitis, emphysema) and current bronchitis symptoms was compared in former elite male athletes (n = 1282) who represented Finland between 1920 and 1965 at least once in international competitions and controls (n = 777) who, at the age of 20, were classified as healthy and who responded to a questionnaire in 1985. The presence of disease and symptoms was identified from the questionnaire and, in the case of asthma, also from a nationwide reimbursable medication register. The death certificates of the subjects of our original cohort who died between 1936 and 1985 were also investigated to determine the cause of death. RESULTS: The occurrence of the pulmonary diseases was associated with age, smoking habits, occupational group, and a history of exposure to chemicals. After adjusting for these variables, athletes who participated in mixed sports (odds ratio (OR) 0.46, 95% confidence interval (CI) 0.23 to 0.92) and power sports (OR 0.43, 95% CI 0.21 to 0.87) had lower odds ratios for emphysema, and endurance sports athletes had a lower odds ratio for the presence of at least one pulmonary disease (OR 0.53, 95% CI 0.28 to 0.98) when compared with controls. Athletes also tended to have fewer reimbursable medications for asthma and fewer current symptoms for chronic bronchitis. Between 1936 and 1985 two controls but none of the athletes died of asthma. CONCLUSIONS: The lifetime occurrence of asthma or other pulmonary diseases is not increased in former elite athletes, and exercise alone, even in a cold environment, did not appear to increase the prevalence of asthma, at least up to the mid 1980s.     

A case of PTH related protein-producing large cell carcinoma of the lung]

The aim of this study was to determine the prevalence of symptoms suggestive of asthma in children aged 7-14 years in Ankara, Turkey. For this purpose, the recently developed ISAAC (International Study for Asthma and Allergies in Childhood) questionnaire supplemented with six additional questions was issued to parents of 3154 primary school children from 12 schools. A separate page with questions regarding risk factors was also added to the questionnaire. The response rate was 88.3%. The cumulative and 12-month prevalence of wheezing were 14.4 and 4.7% respectively. The prevalence of physician-diagnosed asthma was 8.1%. A family history of atopy was found to be the strongest risk factor for having ever had wheezing (odds ratio (OR) = 2.89, 95% confidence interval (CI) = 2.32-3.60), wheezing in the past 12 months (OR = 3.21, CI = 2.21-4.67), and severe attack (OR = 2.41, CI = 1.36-4.25). Passive smoking was a risk only for having ever had wheezing (OR = 1.33, CI = 1.03-1.76). Increasing age was associated with a lower risk of current wheezing (OR = 0.85, CI = 0.81-0.90) and severe attack (OR = 0.77, CI = 0.67-0.88). Gender, socio-economic level and pet ownership did not appear to be risk factors for asthma-related symptoms. This study, the first epidemiological survey in Ankara, Turkey, using the ISAAC protocol, clearly shows that symptoms suggestive of asthma, albeit lower than in most European countries, are quite common and constitute a major health problem in Turkey.     

Quantification of alterations in structure and function of elastin in the arterial media

The effect of environmental tobacco smoke (ETS) exposure on adults with asthma has not been well characterized. In a prospective cohort study of 451 nonsmoking adults with asthma, we evaluated the impact of ETS exposure on asthma severity, health status, and health care utilization over 18 mo. There were 129 subjects (29%; 95% CI, 25-33%) who reported regular ETS exposure, falling into three categories: exposure at baseline but none at follow-up (n = 43, 10%), no baseline exposure and new exposure at follow-up (n = 56, 12%), and exposure at both baseline and follow-up (n = 30, 7%). In cross-sectional analyses, subjects with baseline ETS exposure had greater severity-of-asthma scores (score difference, 1.7; 95% CI, 0. 2-3.1), worse asthma-specific quality of life scores (score difference, 3.5; 95% CI, 0.03-7.0), and worse scores on the Medical Outcomes Study SF-36 physical component summary (score difference, 3. 0; 95% CI, 0-6.0) than unexposed subjects. They also had greater odds of emergency department visits (odds ratio [OR] = 2.1; 95% CI, 1.2-3.5), urgent physician visits (OR = 1.9; 95% CI, 1.1-3.3), and hospitalizations (OR = 1.9; 95% CI, 1.02-3.6). In longitudinal follow-up, subjects reporting ETS cessation showed improvement in severity-of-asthma scores (score reduction, -3.2; 95% CI, -4.4 to -2. 0) and physical component summary scores (score increase, 5.3; 95% CI, 2.6-8.1). Environmental tobacco smoke cessation decreased the odds of emergency department visits (OR = 0.4; 95% CI, 0.2-0.97) and hospitalizations (OR = 0.2; 95% CI, 0.04-0.97) after adjustment for covariates. Environmental tobacco smoke initiation was associated with greater asthma severity only in subjects with high-level (>= 3 h/wk) exposure (score increase, 1.4; 95% CI, 0.03-2.7). In conclusion, self-reported ETS exposure is associated with greater asthma severity, worse health status, and increased health care utilization in adults with asthma.     

Health conditions among the currently employed

This report presents national estimates of the prevalence and incidence of selected health conditions and their work-related consequences among currently employed persons 18 years of age and over. The major health conditions presented include back pain; hand discomfort; dermatitis; eye, nose, and throat irritation; and work injuries. Also presented are estimates of the distribution of workers on selected physical activities and exposures at work. Data are presented by age, sex, race, ethnicity, education, and broad occupational category.     

Nested case-control study of esophageal cancer in relation to occupational exposure to silica and other dusts

BACKGROUND: Standardized proportionate mortality ratio (SPMR) was found to be 2.2 (95% CI = 1.3-3.5) for esophageal cancer (EC) among workers exposed to refractory brick dust in a large iron-steel complex in China. METHODS: A nested case-control design within a cohort of industrial workers. One hundred and twenty-five EC cases and 250 controls were identified from the death registry file. Interviews were conducted of the next of kin for past exposure information on job, domestic, and lifestyle factors. History of occupational exposure to various dusts was reconstructed from personnel files and by interviewing colleagues utilizing a job-exposure matrix. RESULTS: After adjusting for confounders, occupational exposure to silica dust was the most important risk factor among all variables investigated, with a 2.8-fold risk and a clear dose-response by length of exposure. Alcohol drinking (OR = 1.8) and coal cooking (OR = 2.0) were risk factors and high consumption of fruit diet (OR = 0.5) and meat diet (OR = 0.6) were protective factors. CONCLUSIONS: The relationship between occupational exposure to silica dust and the risk of EC found in an earlier SPMR study was confirmed. Ingestion of silica particles after lung clearance may increase the risk of EC among workers exposed to silica.     

Nature and incidence of self-reported adolescent work injury in Minnesota

Most studies of adolescent work-related injury that have been published to date have been confined to administratively collected data available through state or national departments of labor and industry and/or occupational safety and health administrations. These data do not contain information on the severity or the sequelae of injuries. In addition, estimates of incidence may be biased due to inadequate data on the nature, amount, and seasonal variability of work done by adolescent workers. The present study is a cross-sectional survey of work and work injuries of 3,051 10th through 12th grade students from 39 high schools throughout Minnesota. Injury was defined as an event which caused any of the following: loss of consciousness, seeking medical care, and/or restricting normal activities for at least 1 day. The average hours of work per week during the summer and during the school year were 30 (95% Confidence Interval [CI] = 27, 33) and 16 (95% CI = 15, 17), respectively. There was no difference in hours worked between ethnic minorities and white students. The rate of reportable injuries was 12 per 100,000 hr worked (95% CI = 7, 18) for rural and 13 per 100,000 hr worked (95% CI = 7, 28) for urban females, 16 (95% CI = 9, 22) per 100,000 hr for urban males, and 20 (95% CI = 12, 28) per 100,000 hr for rural males. Ongoing medical problems were reported by 26% of the injured workers. Previous estimates of work-related injury to adolescents may have been low. More study is required to clearly define the incidence of injury and risk factors for these injuries.     

Evaluation of the Brusini glaucoma staging system for follow-up in glaucoma

There is evidence that bronchial responsiveness to allergen is quantitatively correlated with bronchial responsiveness to nonspecific stimuli in subjects with allergic asthma. This association has been questioned in occupational asthma due to low molecular weight substances. It was the aim of this study to assess the quantitative association of bronchial responsiveness to methacholine (MCH) and platinum salts (Pt), in the form of hexachloroplatinic acid, in workers with occupational asthma due to Pt salts. Fifty-seven subjects with exposure to Pt, work-related asthma, and a positive bronchial challenge with Pt underwent skin prick test with Pt and bronchial challenge with MCH. Using the provocation concentration causing a > or = 50% fall in specific airway conductance (PC50sGaw(Pt)) as a dependent variable, anamnestic data (period from first symptoms to removal, period between removal from exposure and diagnosis, and smoking), season of the investigation, skin prick tests with environmental allergens, total immunoglobulin E (IgE), skin reactivity to Pt (Pt concentration causing a 2 mm wheal), and PC50sGaw(MCH) were included as independent variables for regression analysis. Fifty-two subjects (91%) showed a PC50sGaw(MCH) < 8 mg.mL-1 (geometric mean for all subjects 1.6 mg.mL-1). Responsiveness to Pt varied widely between subjects (geometric mean of PC50sGaw(Pt) 9 x 10(-5) mol.L-1, range 2 x 10(-7) to 10(-2) mol.L-1). There was no univariate correlation between bronchial responsiveness to MCH and Pt, but there was a correlation between skin reactivity to Pt and PC50sGaw(Pt) (r = 0.6). This association could not be improved by considering PC50sGaw(MCH), the period from first symptoms to removal, or the period between removal from exposure and diagnosis. The parameters that showed the highest (negative) associations with PC50sGaw(Pt) were skin reactivity to Pt and the period between removal from exposure and diagnosis (r = 0.65). We conclude that there is a moderate association between bronchial responsiveness to platinum salts and skin reactivity to platinum salts. However, there is no association between methacholine responsiveness and bronchial responsiveness to allergen in occupational asthma due to platinum salts.     

Scorpion stings in Spain. Popular therapies, proverbs and pharmacopoeias]

There is evidence that bronchial responsiveness to allergen is quantitatively correlated with bronchial responsiveness to nonspecific stimuli in subjects with allergic asthma. This association has been questioned in occupational asthma due to low molecular weight substances. It was the aim of this study to assess the quantitative association of bronchial responsiveness to methacholine (MCh) and platinum salts (Pt), in the form of hexachloroplatinic acid, in workers with occupational asthma due to platinum salts. Fifty seven subjects with exposure to Pt, work-related asthma, and a positive bronchial challenge with Pt, underwent skin prick tests with Pt and bronchial challenge with MCh. Using the provocation concentration causing a > or = 50% fall in specific airway conductance (PC50sGaw(Pt)) as dependent variable, anamnestic data (period from first symptoms to removal, period between removal from exposure and diagnosis, and smoking), season of the investigation, skin prick tests with environmental allergens, total immunoglobulin E (IgE), skin reactivity to Pt (Pt concentration causing a 2 mm wheal), and PC50sGaw(MCh) were included as independent variables for regression analysis. Fifty two subjects (91%) showed a PC50sGaw(MCh) < 8 mg.mL-1 (geometric mean for all subjects 1.6 mg.mL-1). Responsiveness to Pt varied widely between subjects (geometric mean of PC50sGaw 9 x 10-5 mol.L-1, range 2 x 10-7 to 10-2 mol.L-1). There was no univariate correlation between bronchial responsiveness to MCh and Pt, but there was a correlation between skin reactivity to Pt and PC50sGaw(Pt) (r = 0.6). This association could not be improved by considering PC50sGaw(MCh), the period from first symptoms to removal, or the period between removal from exposure and diagnosis. The parameters that showed the highest (negative) associations with PC50sGaw(Pt) were skin reactivity to Pt and the period between removal from exposure and diagnosis (r = 0.65). We conclude that there is a moderate association between bronchial responsiveness to platinum salts and skin reactivity to platinum salts. However, there is no association between methacholine responsiveness and bronchial responsiveness to allergen in occupational asthma due to platinum salts.     

Occupational respiratory allergy in bakery workers: a review of the literature

Baker's asthma has long been recognized as a serious disease among workers in the bakery industry and the number of cases with baker's asthma is steadily increasing. This paper presents a review of the available literature on baker's allergy with a special focus on the allergens involved, the epidemiologic research and issues on exposure assessment, evidence of exposure-response-relationships, and possible prevention strategies. A large number of potential allergens have been identified and are described here. At present little is known about the incidence of baker's allergy. On the other hand, a large number of cross-sectional studies have been performed, showing that sensitization and work-related symptoms are common among bakery workers. Only atopy and exposure level have consistently been reported as determinants of this occupational disease. Age, gender, and smoking habits do not seem to be associated with sensitization or work-related respiratory symptoms. Recently, immunochemical methods have been developed to measure specific allergens in the bakery industry, which have been used to unravel the role of allergen exposure in the development of baker's asthma. Clear exposure-response-relationships have been found. The implications of these recent findings for prevention strategies and standard setting are discussed.     

Specific bronchial provocation tests with flour in the diagnosis of occupational bronchial asthma

The gold standard in the diagnosis of occupational asthma is the specific bronchial provocation test (sBPT), but other diagnostic criteria have been proven to have a similar sensitivity, mainly in asthma due to high molecular weight compounds. In order to assess wether some clinical findings can predict the positive response to sBPT, we studied 37 subjects (14 millers and 23 bakers) with suspected occupational asthma who underwent sBPT with wheat flour dust (dust exposure in a small cabin: geometric mean 12.1 mg/m3 for up to 30 min). A positive response to sBPT (FEV1 > 20%) was elicited in 20 subjects (11 early, 4 late, and 5 dual responses). There was no significant difference between subjects with positive or negative sBPT as regards mean age, smoking, length of employment, duration of symptoms, atopy (skin positivity to one or more common allergens) and PD20FEV1 methacholine. The percentage of subjects with work-related symptoms was significantly higher in subjects with positive sBPT with respect to subjects with negative sBPT (81% versus 41.2%, p < 0.01 by chi 2 test); furthermore, FEV1 was significantly lower in subjects with positive sBPT. The percentage of positive skin response to wheat flour extract (mean wheal diameter > or = 3 mm) was mildly but not significantly higher in subjects with positive sBPT (68.4% versus 41.2%). None of the following clinical factors (age < 35 years, asthma symptoms pre-existing occupational exposure, non smokers, atopy and bronchial hyperresponsiveness to methacholine), alone or in combination, were associated with higher prevalence of positive sBPT. We conclude that the response to sBPT in subjects with suspected occupational asthma due to flour dust can not be adequately predicted by other clinical, allergologic and functional data. Therefore, sBPT with flour dust should always be performed in subjects with suspected occupational asthma.     

Nontyrosine crystalloids in fine-needle aspiration specimens of the parotid gland: a report of two cases and review of the literature

Transitional-cell carcinoma is the dominant histological type of malignant tumors of the urinary bladder. There is limited information on risk factors for non-transitional-cell carcinoma (NTCC) of the bladder. We used data from 9 case-control studies on bladder cancer from 6 European countries to examine the association between NTCC, tobacco smoking and occupation. Information on 146 cases diagnosed with NTCC were matched by age, gender and study center to 727 non-cancer population or hospital controls and also with 722 transitional-cell-bladder-cancer controls. Lifetime smoking and occupational history were evaluated. A statistically significant excess risk for NTCC was observed for current smoking [odds ratio (OR) = 3.61, 95% confidence interval (CI) 2.08-6.28]. The risk increased with higher tobacco consumption (OR for highest tertile of pack-years = 7.01, 95% CI 3.60-13.66). The risks were higher for squamous-cell carcinomas than for other types of NTCC. Among major occupational groups, a significant excess risk was seen for field-crop and vegetable-farm workers (OR = 2.06, 95% CI 1.03-4.10). These results indicate that NTCC of the bladder is associated with smoking and specific occupations. The risk pattern seems to differ, in part, from that observed for transitional-cell carcinoma of the bladder.     

Bronchial asthma: do boys or girls have the highest incidence?

The aim of the study was to assess the gender related prevalence of asthma and asthma symptoms in schoolchildren. The survey was performed using standardized ISAAC questionnaire in two age groups: 6-7 yr. (n = 2281; girls 49.7%) and 13-14 yr. (n = 4849; girls 49.8%). It was revealed that in older group the prevalence of ever diagnosed asthma was lower in girls than in boys (2.0% versus 3.3%; odds ratio [OR] = 0.58; p = 0.004). But the prevalence of symptoms: wheeze ever (OR = 1.16; p = 0.056), current wheeze (last 12 mo) (OR = 1.26; p = 0.029), current exercise wheeze (OR = 1.40; p = 0.0008), current night cough (OR = 1.67; p = 0.0001) were higher in girls than in boys. However, in younger group of schoolchildren the prevalence of ever diagnosed asthma and asthma symptoms were higher in boys (5.1% male versus 3.5% female). The girls in comparison to boys revealed lower risk of ever asthma diagnosis (OR = 0.66; p = 0.056) and symptoms: wheeze ever (OR = 0.63; p = 0.0001), current wheeze (OR = 0.69; p = 0.003), current exercise wheeze (OR = 0.59; p = 0.008) and current night cough (OR = 0.70; p = 0.0003).     

Birth characteristics and asthma symptoms in young adults: results from a population-based cohort study in Norway

There is evidence that the origin of obstructive lung disease may be traced back to foetal life. The associations between birth characteristics and asthma symptoms were studied in a random population sample of young Norwegian adults. Respiratory symptoms were recorded in a population-based questionnaire survey. The records of all subjects aged 20-24 yrs were linked with the Medical Birth Registry of Norway. Of 868 subjects born in Norway, there were 690 (79%) responders. The associations between asthma symptoms and birth characteristics were analysed by logistic regression, adjusted for possible confounding factors. Asthma symptoms in young adults were inversely associated with birth weight (odds ratio (OR)wheeze=0.82; 95% confidence interval (CI)=0.69-0.96x500 g increase in birth weight(-1))), and after adjustment for gestational age, birth length, parity and maternal age (ORwheeze=0.69; 95% CI=0.50-0.95x500 g increase in birth weight(-1)). The association did not vary according to adult smoking habits or atopic status and remained when premature and low weight births were excluded (ORwheeze=0.73; 95% CI=0.60-0.90x500 g increase in birth weight(-1)). The association was consistent for all asthma symptoms. Adjusted for birth weight, asthma symptoms were further associated with low gestational age, high birth length and low maternal age. In a random sample of young adults, asthma symptoms were strongly associated with low birth weight, an association driven by the full-term births within the normal birth weight range. The findings show that the risk for adult asthma is partly established early in life and suggest that poor intrauterine growth is involved in the aetiology of asthma.     

Under the volcano: fire, ash and asthma?

AIMS: To investigate the prevalence of respiratory symptoms in known asthmatics, following exposure to airborne volcanic ash particles caused by the eruptions of Mount Ruapehu, New Zealand, commencing September 1995. METHOD: A one page postal questionnaire was sent to 1392 previously identified asthmatics 2 months after the first major eruption. RESULTS: Two hundred and thirty seven subjects had moved from the area, died or gone overseas since the original contact 4 years previously; therefore the target population was 1155 subjects of whom 361 lived in the exposed area and 794 in the nonexposed areas. The response rates were 246 (68.1%) in the exposed group and 477 (60.1%) in the nonexposed group making a total of 723 individuals. The prevalence of nocturnal shortness of breath in the last two months was 29.3% in the exposed group and 24.7% in the nonexposed (OR = 1.26, 95% CI; 0.83-1.78). Similarly 30.9% of the exposed group had an asthma attack in the last 2 months compared to 31.9% of the nonexposed group (OR = 0.96, 95% CI; 0.69-1.33). Finally, 48.4% of the exposed group used asthma medication in the 2 months following the eruption in comparison to 53% of the nonexposed group (OR = 0.83, 95%, CI; 0.61-1.12). CONCLUSIONS: The study showed no association between living in an area exposed to volcanic ash particles and either asthma symptoms or the use of asthma medication. There was a small but nonsignificant increase in nocturnal shortness of breath in the exposed group.     

Back pain and agricultural work among farmers: an analysis of the Colorado Farm Family Health and Hazard Surveillance Survey

BACKGROUND: Back pain is the most prevalent occupational health problem experienced by much of the world's workforce. However, agricultural work-related back pain occurring among US farmers working on small operations or family farms is usually not included in surveillance. With data collected by Colorado Farm Family Health and Hazard Surveillance Survey, this study reports characteristics of and risk factors for back pain among adult farmers living in eight Colorado counties. METHODS: A stratified probability sample of 500 farms was selected in proportion to the number of farms in study areas. During the 4-year period from 1993 through 1996, 458 farms were enrolled in the study and 759 farmers were interviewed using a questionnaire. Information on self-reported back pain and potential risk factors among 742 white farmers was evaluated and reported here. RESULTS: A total of 194 farmers (26.2%) reported to have had at least one episode of back pain lasting for 1 week or more. Males had a slightly higher prevalence of back pain than females (28.6% vs. 22.5%) and the lower back was the predominantly affected part of body among both males and females. In 45.4% of males and 43.9% of females back pain was brought on by repeated activities. Males' activities at work were more likely to cause back pain while females' activities at home were more likely to cause back pain. Three factors were found to be significantly associated with back pain: being depressed (odds ratio (OR) = 3.68, 95% confidence interval (CI) = 2.23-6.09), farming/ranching as main activities (OR = 1.66, CI = 1.17-2.36), and worked in agriculture for 10 to 29 years (OR = 1.62, CI = 1.14-2.30). CONCLUSIONS: Our analyses indicate that back pain is an occupational health problem among farmers on small operations or family farms and that back pain affected males and females differently. The finding of significant positive associations between depression, farming activities, and back pain warrants further attention.