Depressive symptoms as a risk factor for unintentional injury: a cohort study in a rural county.

OBJECTIVE: The authors used data from a population based prospective cohort study to determine if depressive symptoms predicted incidence of unintentional injury. METHODS: The Keokuk County Rural Health Study, based in Iowa, is a prospective cohort study of health status that includes injury outcomes. Depressive symptoms were measured using the 11-item Center for Epidemiologic Studies Depression Scale at the beginning of the study on 1493 participants. Quarterly follow up phone calls were made to measure injury incidence. RESULTS: 471 injuries were reported for an overall injury rate of 9.8 per 100 person-years. Crude injury rates were significantly higher for those with depressive symptoms (p = 0.0003). Those with depressive symptoms had a 41% increased risk for injury after controlling for antidepressant medication use, gender, prior injury, income, and sleepiness (RR = 1.41, 95% CI 1.10 to 1.80). Depressive symptoms remained a risk factor for injury regardless of current antidepressant medication use (no medication use, RR = 1.43, 95% CI 1.09 to 1.88; medication use, RR = 1.31, 95% CI 0.76 to 2.26). CONCLUSIONS: Depressive symptoms were found to be risk factors for unintentional injury. Medical practitioners should consider talking about safety with their patients, especially those reporting symptoms of depression, and recognize that an increased risk for injury remains until the depressive symptoms subside.

Fatal motor vehicle crashes in rural and urban areas: decomposing rates into contributing factors.

OBJECTIVES: Motor vehicle crash fatality rates have been consistently higher in rural areas than in urban areas. However, the explanations for these differences are less clear. In this study the decomposition method was used to explore the factors associated with increased fatal crash involvement rates in rural communities. DESIGN: Using national databases, the fatal crash incidence density was decomposed into the product of three factors: the injury fatality rate, the crash injury rate, and the crash incidence density. RESULTS: As expected, the fatal crash incidence density was more than two times higher in rural than in urban areas. This was driven primarily by the injury fatality rate, which was almost three times higher in rural areas. CONCLUSIONS: Further research should examine the relative roles of crash severity and the timely receipt of definitive medical care after a crash.

Risk factors for agricultural injury: a case-control analysis of Iowa farmers in the Agricultural Health Study.

The purpose of this case-control study nested in the Agricultural Health Study was to assess risk factors for agricultural injury among a large group of Iowa farmers. A questionnaire sent to 6,999 farmers identified 431 cases who had a farm work-related injury requiring medical advice/treatment in the previous year and 473 controls who had no injury in the previous year. We assessed several potential risk factors for injury. A multiple logistic regression analysis showed significant associations between farm work-related injury and weekly farming work hours (> or = 50 hours/week) (OR = 1.65; 95% CI = 1.23-2.21), the presence of large livestock (OR = 1.77; 95% CI = 1.24-2.51), education beyond high school (OR = 1.61; 95% CI = 1.21-2.12), regular medication use (OR = 1.44; 95% CI = 1.04-1.96), wearing a hearing aid (OR = 2.36; 95% CI = 1.07-5.20), and younger age. These results confirm the importance of risk factors identified in previous analytic studies and suggest directions for future research in preventive intervention strategies to reduce farm work-related injuries.

Health risk factors and occupation among Iowa workers.

BACKGROUND: Health behaviors represent major risks for premature morbidity and mortality. This study aimed to establish whether health risks varied substantially across occupational groups. METHODS: We focused on the 2223 Iowa Behavioral Risk Factor Surveillance System (BRFSS) subjects who reported, in 1999, that they were currently working. RESULTS: Even after controlling for age and gender, we found significant associations between occupation and health risk factors. We found these associations among the different categories of health risk factors, including insurance/access, health conditions, preventive behaviors, and screening behaviors. CONCLUSIONS: The considerable differences in the prevalence of risk factors for chronic disease and injury across occupational groups in Iowa underscore the need for nationwide ongoing collection of occupational status in the BRFSS. These national data on the distribution of risk factors across occupations will support development of more targeted prevention interventions.

Nested case-control analysis of high pesticide exposure events from the Agricultural Health Study.

BACKGROUND: A nested case-control analysis of high pesticide exposure events (HPEEs) was conducted using the Iowa farmers enrolled in the Agricultural Health Study (AHS). METHODS: In the 12 months of the study, 36 of the 5,970 farmer applicators randomly chosen from the AHS cohort (six per 1,000 farmer applicators per year) met our definition of an HPEE, by reporting "an incident with fertilizers, weed killers, or other pesticides that caused an unusually high personal exposure" resulting in physical symptoms or a visit to a health care provider or hospital. Eligibility criteria were met by 25 HPEE cases and 603 randomly selected controls. RESULTS: Significant risk factors for an HPEE included: poor financial condition of the farm which limited the purchase of rollover protective structures OR = 4.6 (1.5-16.6), and having a high score on a risk acceptance scale OR = 3.8 (1.4-11.2). Other non-significant factors were also identified. CONCLUSIONS: The limited statistical power of this study necessitates replication of these analyses with a larger sample. Nonetheless, the observed elevated odds ratios of an HPEE provide hypotheses for future studies that may lead to preventive action.

Risk factors for work-related injury among male farmers in Iowa: a prospective cohort study.

Agriculture is one of the most hazardous occupations in the United States. We examined the work-related injury rate and risk factors among 290 Iowa male principal farm operators using a population-based, prospective study. Baseline data were collected between 1991 and 1994, and injury events were surveyed in the fall of 1995. Cumulative incidence of farmwork-related injury during the previous year was 10.5%. We found that depressive symptoms (odds ratio, 3.22; 95% confidence interval, 1.04 to 9.99) and the number of hours working with animals (odds ratio, 2.14; 95% confidence interval, 1.04 to 4.44) were associated with the incidence of farmwork-related injuries.

Farm-related dermatoses in Iowa male farmers and wives of farmers: a cross-sectional analysis of the Iowa Farm Family Health and Hazard Surveillance Project.

Agricultural workers are exposed to a variety of hazards that increase their risk for dermatitis. Nevertheless, the prevalence, patterns, and risk factors for dermatitis have not been well characterized among farmers in the United States. We assessed the prevalence and risk factors for dermatitis among 382 male farmers and 256 wives of farmers in Iowa using a cross-sectional study design. From 1992 to 1994, we collected data on potential risk factors and dermatitis. The results showed that 9.6% of male farmers and 14.4% of wives of farmers reported dermatitis during the previous 12-month period. In multivariable models, a history of allergy (odds ratio [OR], 8.2; 95% confidence interval [CI], 2.0 to 33.3) was strongly associated with dermatitis among male farmers. Among wives of farmers, some college education (OR, 3.4; 95% CI, 1.1 to 9.9) and exposure to petroleum products (OR, 3.1; 95% CI, 1.3 to 7.0) were associated with dermatitis. These results can be used to form preventive efforts in controlling farmwork-related exposures.

Risk factors for back pain among male farmers: analysis of Iowa Farm Family Health and Hazard Surveillance Study.

BACKGROUND: Back pain causes considerable morbidity, disability, and economic loss among workers. Farmers handle heavy objects, often in awkward postures. However, the prevalence of back pain among farmers and the risk factors associated with back pain are not well known. METHODS: In this study, we assess the frequency of risk factors for back pain among 287 Iowa male farmers. From 1992 to 1994, using a mail questionnaire, we collected data on potential risk factors for back pain. Eighteen months later, we surveyed occurrence of back pain as the outcome measure. RESULTS: Thirty-one percent of farmers reported having daily back pain for a week or more during the past 12 months compared to 18.5% in the general working population. Using a multiple logistic regression model, we found two factors associated with back pain: 45-59 years of age (OR = 2.13, 95% CI 1.02-4.43) and having a non-agricultural job as the major occupation (OR = 2.02, 95% CI 0.98-4.17, P = 0.055). CONCLUSIONS: Farmers had a significantly higher prevalence of back pain than the general working population. Middle-aged farmers and those with additional non-agricultural jobs had the highest risk for back pain.

Respiratory symptoms: associations with pesticides, silos, and animal confinement in the Iowa Farm Family Health and Hazard Surveillance Project.

BACKGROUND: Farmers are at risk for airways diseases resulting from exposures which include organic agents and chemicals on the farm. Few data on airways disease and farm exposures are available from population-based studies. The Iowa Farm Family Health and Hazard Surveillance Project provided the opportunity to assess associations between symptoms of airway disease and several farm exposures, including pesticides, grain dust, animal confinement, and exposures from silos, in a population-based study. METHODS: A stratified two-stage cluster sample was used to provide a representative farmer sample from the state. Participants provided questionnaire responses concerning demographic, respiratory symptoms, smoking, and exposure information. Associations between farm exposures and airways disease symptoms were assessed in the 385 farmer participants using chi(2) analysis and logistic regression analysis adjusting for age and smoking. RESULTS: The most frequently reported respiratory symptoms were flu-like symptoms in connection with dusty work (22%), dyspnea (21%), and phlegm (15%). Current smoking was uncommon (13%). Among farmers, applying pesticides to livestock was associated with significantly increased odds of phlegm (OR = 1.91, 95% CI 1.02-3.57), chest ever wheezy (OR = 3.92, 95% CI 1.76-8.72), and flu-like symptoms (OR = 2.93, 95% CI 1.69-5.12) in models adjusting for age and smoking. Conventional vertical silos were significantly associated with increased odds of chest ever wheezy (OR = 2.75, 95% CI 1.23-6.12) and flu-like symptoms (OR = 2.40, 95% CI 1.31-4.37). There were also significant associations between several respiratory symptoms and the presence of animal confinement facilities on the farm. CONCLUSIONS: The association between insecticide application to livestock and symptoms of airways disease is a new finding that could lead to further study of specific airway responses and exposures associated with this practice. Results confirming associations between respiratory symptoms and conventional vertical silos may be important in future studies aimed at prevention and control of exposures in those farm buildings.

Prevalence of elevated blood leads and exposure to lead in construction trades in Iowa and Illinois.

BACKGROUND: Despite lowering of the permissible exposure level for lead in construction from 200 to 50 microg/m3 in 1993, excessive lead exposure continues to be a problem. Relatively little data are available from the Midwestern U.S. on the environmental lead concentrations generated during various construction activities and the potential for worker exposure. This study characterized the prevalence of blood lead concentrations in high-risk construction trades in Iowa/Illinois, and identified risk factors for occupational exposure to lead in these construction workers. METHODS: A sample of 459 workers was selected from the total population of all union members from trade groups of painters, plumbers/pipefitters, ironworkers, laborers, and electricians. Participants completed an interviewer-administered questionnaire obtaining information on demographics, symptoms, occupational history, work practices, personal protective equipment, and training. Venous blood samples were collected from each participant and analyzed for blood lead (using atomic absorption spectroscopy) and free erythrocyte protoporphyrin levels. RESULTS: Blood lead levels (BLLs) of construction workers ranged from 0.1 to 50 microg/dL. Geometric mean blood lead concentrations by trade group were: laborers (7.6 microg/dL, n = 80); painters (5.9 microg/dL, n = 83); ironworkers (5.2 microg/dL, n = 87); plumbers (4.4 microg/dL, n = 82); electricians (2.4 microg/dL, n = 91). Blood lead levels for painters and laborers were significantly higher than other trade groups, and levels for electricians were significantly lower (p < 0. 01). Participants reported working primarily on commercial and industrial projects including new construction, renovation, and demolition. There were significant differences between the types of projects performed by different trade groups with laborers performing more highway/bridge renovation (p < 0.01), and plumbers reporting more residential remodeling (p = 0.05), repair of water lines containing lead (p = 0.04), or work on lead joints (p < 0.01). In addition to trade, elevated blood lead levels were associated with the type of construction project (especially bridge renovation and residential remodeling) and activities that include welding, cutting, rivet busting. The age of the home in which the worker lived, and hobbies such as casting/smelting lead for bullets or sinkers, were also important risk factors. Compliance with OSHA's Construction Lead Standard, and implementation of good occupational health and safety practices in general, was poor. CONCLUSIONS: Blood lead levels of 459 construction workers differed by the type of trade, type of project and specific job activity owing to differences in the inherent exposure potential of each task. Although the numbers of workers performing lead abatement projects were small, the trend for lower BLL in this group provides evidence that training, implementation of engineering controls, and proper use of personal protective equipment such as respirators is effective in controlling lead poisoning.

Occupational injuries among older workers with disabilities: a prospective cohort study of the Health and Retirement Survey, 1992 to 1994.

OBJECTIVES: We tested the hypothesis that among older workers, disabilities in general, and hearing and visual impairments in particular, are risk factors for occupational injuries. METHODS: Using the first 2 interviews of the Health and Retirement Study, a nationally representative survey of Americans aged 51 to 61 years, we conducted a prospective cohort study of 5600 employed nonfarmers. RESULTS: Testing a logistic regression model developed in a previous cross-sectional study, we found that the following occupations and risk factors were associated with occupational injury as estimated by odds ratios: service personnel, odds ratio = 1.71 (95% confidence interval = 1.13, 2.57); mechanics and repairers, 3.47 (1.98, 6.10); operators and assemblers, 2.33 (1.51, 3.61); laborers, 3.16 (1.67, 5.98); jobs requiring heavy lifting, 2.05 (1.55, 2.70); self-employment, 0.50 (0.34, 0.73); and self-reported disability, 1.58 (1.14, 2.19). Replacing the general disability variable with specific hearing and visual impairment variables, we found that poor hearing (1.35 [0.95, 1.93]) and poor sight (1.45 [0.94, 2.22]) both had elevated odds ratios. CONCLUSIONS: Poor sight and poor hearing, as well as work disabilities in general, are associated with occupational injuries among older workers.

Occupational injuries among older workers with visual, auditory, and other impairments. A validation study.

This study aims to validate a previously defined model of the risk of occupational injuries among older workers with visual, auditory, or other impairments. That model was based upon the Health and Retirement Study (HRS). The previous logistic regression model was recalculated using data from the 1994 National Health Interview Survey (NHIS). The parameter estimates for impaired hearing (.181 in NHIS, 1.55 in HRS), impaired vision (2.42 in NHIS, 1.48 in HRS), and self-employment (0.22 in NHIS, 0.49 in HRS) were in same direction and of roughly the same magnitude. The previously defined model was confirmed using NHIS data. The data suggest that as the workforce ages, more attention must be paid to the accommodation of disabilities in the workplace, especially sensory impairments-poor vision and hearing.

Work-related injuries among Iowa farm operators: an analysis of the Iowa Farm Family Health and Hazard Surveillance Project.

In 1994, the Iowa Farm Family Health and Hazard Surveillance Project carried out a two-stage, stratified, cluster survey of Iowa farms using a mail survey. With data from this representative sample of Iowa farmers, we examined the associations between farm-work-related injuries and possible risk factors for 390 principal farm operators. Forty (10.3%) of these operators reported being injured while doing farm work. We developed a logistic regression to assess associations between potential risk factors and injury. We found three factors significantly associated with injury: younger age (odds ratio [OR] = 3.1, confidence interval [CI] = 1.1-9.3), having an impairment or health problem that limits work (OR = 2.4, CI = 1.5-3.8), and hand or arm exposure to acids or alkalis (OR = 2.6, CI = 1.1-5.9). In the univariate analysis, safety training did not seem to protect farmers from injuries.

Factors associated with fatalities and injuries from hot-air balloon crashes.

CONTEXT: Despite the increased popularity of hot-air balloon flight, data on injuries and fatalities associated with hot-air balloon crashes are limited. OBJECTIVE: To determine factors associated with injury and death in hot-air balloon crashes. DESIGN: Retrospective review of data collected from reports and investigations by the Civil Aeronautics Board and the National Transportation Safety Board. STUDY SUBJECTS: Individuals involved in US hot-air balloon crashes from 1964 to 1995. MAIN OUTCOME MEASURES: Total number of crashes and factors associated with fatality or serious injury. RESULTS: From 1964 to 1995, a total of 495 hot-air balloon crashes involving 1533 persons were reported and included 92 fatalities and 384 serious injuries. Pilot error or incapacitation was determined subjectively by crash investigators to contribute to 85.1% of the crashes. In univariate analysis, collision with the ground was the most significant predictor of a fatality or serious injury (P<.001), and power-line contact was the most significant predictor of fatality (P<.001). In multiple logistic regression, only the type of object struck by a balloon predicted a fatal crash or a fatality or serious injury. CONCLUSIONS: Although a number of factors likely contribute to increased severity of hot-air balloon crashes, the object struck during a crash is most predictive of fatality or serious injury. Preventive efforts are needed to decrease future injuries.

Respiratory symptoms and lung function abnormalities among machine operators in automobile production.

This cross-sectional study was designed to assess differences in prevalence of respiratory symptoms and lung function between machine operators exposed to semisynthetic or soluble metal-working fluids (MWFs) and unexposed assemblers and to assess exposure-response relationships with MWF type, total aerosol, endotoxin, culturable bacteria and fungi. We evaluated 183 machine operators and 66 assemblers from one large automobile transmission plant using questionnaires, spirometry data, and cross-shift assessment of both lung function and respiratory symptoms. We found that airborne exposures to total aerosol, endotoxin, culturable bacteria and fungi were higher in machine operations than in the assembly area. There was a correlation between bulk and airborne culturable bacteria, but not between bulk and airborne culturable fungi. Machine operators had significantly more usual cough, usual phlegm, work-related chest tightness and post-shift symptoms of chest tightness, throat irritation, and cough compared with assemblers. We found exposure-response relationships between respiratory symptoms and total aerosol, as well as culturable fungi and bacteria. Associations with endotoxin were not strong or consistent, possibly because airborne levels were generally low. Cross-shift lung function decrements did not differ between machine operators and assemblers and there were no associations with MWF or specific exposures. The finding of respiratory symptoms at low levels of exposure in this study suggests the need to re-assess total aerosol thresholds. Associations between airborne fungal exposures and respiratory symptoms need further study to characterize sources of exposure other than MWF in machining operations.

Lead poisoning among construction workers renovating a previously deleaded bridge.

This study evaluated lead poisoning among construction workers renovating a previously deleaded bridge. Twelve of 44 tested workers had blood leads exceeding 20 micrograms/dL. One was 50 micrograms/dL and two exceeded 40 micrograms/dL. Following medical intervention, blood leads dropped significantly, while ZPPs did not. Renovation released lead that had been inaccessible during deleading. Workers did not use engineering controls or respirators, change clothes, wash hands, or shower. Intervention included a lead-compliance program with provisions for exposure evaluation, training, hygiene, and engineering controls. Construction contractors and workers need to be aware that deleading of bridges and other structures may not remove lead from inaccessible locations. In particular, owners of these structures should specify provisions for anticipating and controlling this hazard in contracts.

Health impairments among refuse derived fuel workers.

We conducted this study to address concerns regarding a perceived increase in bronchitis, skin rashes, and diarrhea and long term health effects in workers at two Refuse Derived Fuel (RDF) processing plants. We abstracted medical records to assess symptom occurrence, and to identify spirometry and lab abnormalities. Overall FEV1 and FVC showed no decrease over time for workers with more than five years of exposure. The primary self reported symptoms were low back pain and headaches followed by skin rashes, colds, 'flu', hay fever and ear problems. Conclusions from this analysis are limited by lack of standardized protocols or a control group. However, results from this analysis pointed out potential occupational health problems among RDF workers for future epidemiological and environmental studies.

Occupational injuries among workers with disabilities: the National Health Interview Survey, 1985-1994.

CONTEXT: As the baby boom generation ages, more people will be working with disabilities, but we have little information regarding how disabilities affect risk for occupational injury. OBJECTIVE: To test the hypothesis that work-limiting disabilities in general and hearing and visual impairments in particular are risk factors for occupational injuries. DESIGN: Retrospective cohort study. SETTING: The National Health Interview Survey (NHIS), 1985 to 1994. PARTICIPANTS: The 459827 participants in the NHIS from 1985 to 1994 who listed "working" as their primary activity, who were not farmers, and who were between 18 and 65 years of age. MAIN OUTCOME MEASURE: Occupational injuries in the year preceding the interview causing a residual impairment at the time of interview. RESULTS: After adjusting for occupation, self-employment, and age, occupational injury was associated with preceding work disability (odds ratio [OR], 1.36; 95% confidence interval [CI], 1.19-1.56); blindness (OR, 3.21; 95% CI, 1.32-7.85); deafness (OR, 2.19; 95% CI, 1.17-4.12); hearing impairment (OR,1.55; 95% CI, 1.29-1.87); upper extremity impairment (OR, 1.46; 95% CI, 1.05-2.05); and arthritis (OR, 1.34; 95% CI, 1.07-1.68). Visual impairment was not associated with a significantly increased risk (OR, 1.37; 95% CI, 0.87-2.17). CONCLUSIONS: Workers with disabilities, especially sensory impairments, appear to have an elevated risk for occupational injury. Further research in the design and evaluation of improved workplace accommodations for workers with these disabilities is needed.

The utility of preliminary surveys to detect the cause of acute metalworking fluid hazards.

This paper describes preliminary studies undertaken to optimize a later epidemiologic study, the aim of which was to identify a causative agent of adverse respiratory effects and dermatitis among production machinists. Two methods were used to rate coolant system hazards. The results of a voluntary plantwide questionnaire with an 18% participation rate showed that both dermatologic and respiratory symptoms were higher among machine operators than among maintenance or assembly workers, that symptoms were not more prevalent early in the week, and that dermatitis may be associated with smoking status; however, the questionnaire was not helpful in rating individual coolant system hazards. The hazard ratings provided by an in-plant expert panel were strongly associated with particular synthetic coolant containing an ethoxylated phenol; however, the resulting design for a later epidemiologic study could not be implemented due to changes in coolants used at the plant.

Dermatitis among automobile production machine operators exposed to metal-working fluids.

This cross-sectional study was designed to assess differences in prevalence of contact dermatitis between machine operators exposed to metal-working fluids (MWFs) and unexposed assemblers, and to assess potential risk factors for contact dermatitis among these machine operators. In their work, machine operators were exposed to either semisynthetic or soluble oil MWFs. We evaluated 158 machine operators and 51 assemblers from one large automobile transmission plant using questionnaires, dermatologist examination of the skin, and dermal dosimetry to measure wetness and metal exposures. We found that machine operators had more combined (definite plus possible) dermatitis (27.2% vs. 13.7%, chi(2) = 3.9, p = 0.05, 1 df) compared with assemblers. Among machine operators, risk factors significantly associated with (combined) dermatitis were subjective assessment of wetness of the work, exposure to semisynthetic as opposed to soluble oil MWF, current cigarette smoking, and increasing worker age. These risk factors suggested preventive and control measures including control of wet work, surveillance program including early self-report of dermatitis, consideration of replacement of semisynthetic with soluble oil MWFs, and strictly limiting smoking among machine operators exposed to MWFs.