Tractor overturn concerns in Iowa: perspectives from the Keokuk county rural health study.

Agriculture remains one of the most hazardous industries in the U.S., with tractor overturns producing the greatest number of agricultural machinery-related fatalities. Rollover protective structures (ROPS) and seatbelts effectively reduce tractor overturn deaths. However, a large proportion of tractors in use in American agriculture are older tractors without ROPS and seatbelts. This article describes the tractor-related responses from participants in a population-based study conducted in Keokuk County, Iowa. This study was designed to measure rural and agricultural adverse health and injury outcomes and their respective risk factors. Questionnaires were partially developed from well-documented national surveys. Questions about agricultural machinery use, presence of safety equipment on the machinery, work practices, and attitudes about farm safety were included. Study participants on farms who owned tractors had an average of 3.1 tractors with an average age of 27 years. Only 39% of the 665 tractors had ROPS. Tractor age was associated with the presence of ROPS; 84% of tractors manufactured after 1984 were ROPS-equipped, whereas only 3% of tractors manufactured before 1960 were ROPS-equipped. ROPS-equipped tractors were significantly more common on larger farms and households with higher income. Only 4% of the farmers reported that their tractors had seatbelts and they wore them when operating their tractors. The results of this study support the findings of other studies, which indicate that many older tractors without ROPS and seatbelts remain in use in American agriculture. Until a dramatic reduction in the number of tractors in the U.S. operated without ROPS and seatbelts is achieved, the annual incidence of 120 to 130 deaths associated with tractor overturns will persist.

A population based study of reporting patterns and characteristics of men who abuse their female partners.

OBJECTIVE: This study estimates the prevalence of male abusive behavior reported by men and their female partners and identifies characteristics of abusive men. DESIGN: Baseline survey from a population based cohort study of general health. SETTING: A rural county in Iowa, USA. SUBJECTS: 572 men and their cohabitating female partners. MAIN OUTCOME MEASURES: Male-to-female physical, emotional, and sexual abuse reported by either partner. RESULTS: In this cohort, 13.6% of men had performed at least one act of physical abuse and 34.9% emotional abuse. More than 45% of abusive men reported their own behaviors. Alcohol problems, antisocial personality characteristics, depressive symptoms, and financial stress were all positively associated with both physical and emotional abuse, but suicidal thoughts were less likely among abusers. CONCLUSION: Identification of common characteristics of abusive men may predict proclivity towards partner violence and barriers to behavior modification.

Vegetable oil sprinkling as a dust reduction method in swine confinement.

The aim of this project was evaluate the effectiveness of an oil sprinkling system as a dust-reduction method for swine production facilities. This article presents the results of the second-year experiment of a multi-year study. The first-year experiment demonstrated that a 5% oil-water emulsion automatically applied at the rate of 3 and 5 g/pig/day achieved a 23% to 34% reduction in total dust. The modifications for the second year experiment included: (1) increasing oil application rate to 7 and 8 g/pig/day, (2) replacing sprinkler heads to achieve a smaller droplet size and a more direct spray pattern on pen-floor surfaces, and (3) more closely matching the treatment and control rooms by stage in the pig production cycle. Four swine finishing rooms were used for this study; two were treatment rooms (soybean oil at 7 g/pig/day, and canola oil 8 g/pig/day) and two were control rooms. The treatment rooms had a low-pressure oil-sprinkling system, which sprinkled 5% oil-to-water mixture 12 times per day, 12 s each time. Concentrations of several environmental contaminants were measured. The average total dust concentration in the control rooms was 1.39 mg/m3. The average total dust concentration in the treatment rooms was 0.65 mg/m3. The treatment reduced dust by an average of 52%, (p = 0.0001). There was no difference in the degree of dust control between soybean oil and canola oil. The respirable dust concentrations were very low in all rooms, and there were no significant differences between rooms in ammonia, carbon dioxide, temperature, or humidity.

Identification of risk factors for non-fatal child injury in a rural area: Keokuk County Rural Health Study.

OBJECTIVE: To identify risk factors for non-fatal injury among rural children. DESIGN: Cross sectional health interview survey, 1994-98. SETTING: A rural Iowa county, not adjacent to a metropolitan area. SUBJECTS: Stratified, random sample of households, including all resident children and adults. MAIN OUTCOME MEASURES: Injury episodes in the past 12 months among children aged 0-17 years and the parental and child characteristics associated with these episodes. RESULTS: Of the 621 children in participating households, 137 or 22.1% were injured during the past 12 months. Children age 5-17 on a sports team were 1.88 times (95% confidence interval (CI) 1.07 to 3.31) more likely than other children to be injured. Children age 12-17 who binge drink were 3.50 times (95% CI 1.31 to 9.50) more likely than other children to be injured. Compared with children not on sports teams, girls on teams were 2.26 times (95% CI 1.02 to 5.13) more likely while boys on teams were 1.60 times (95% CI 0.71 to 3.68) more likely to have an injury episode. Compared with children who did not binge drink, girls binge drinking were 8.11 times (95% CI 1.52 to 43.33) more likely while boys binge drinking were 2.19 times (95% CI 0.70 to 6.84) more likely to have an injury episode. CONCLUSIONS: Local studies such as this can provide useful clues regarding the etiology of injury. Some known and some new potential risk factors including behavioral aspects for childhood non-fatal injury in a very rural area were investigated. It is planned to address these cross sectional findings in future longitudinal follow up of this population.

Integrative assessment of multiple pesticides as risk factors for non-Hodgkin's lymphoma among men.

BACKGROUND: An increased rate of non-Hodgkin's lymphoma (NHL) has been repeatedly observed among farmers, but identification of specific exposures that explain this observation has proven difficult. METHODS: During the 1980s, the National Cancer Institute conducted three case-control studies of NHL in the midwestern United States. These pooled data were used to examine pesticide exposures in farming as risk factors for NHL in men. The large sample size (n = 3417) allowed analysis of 47 pesticides simultaneously, controlling for potential confounding by other pesticides in the model, and adjusting the estimates based on a prespecified variance to make them more stable. RESULTS: Reported use of several individual pesticides was associated with increased NHL incidence, including organophosphate insecticides coumaphos, diazinon, and fonofos, insecticides chlordane, dieldrin, and copper acetoarsenite, and herbicides atrazine, glyphosate, and sodium chlorate. A subanalysis of these "potentially carcinogenic" pesticides suggested a positive trend of risk with exposure to increasing numbers. CONCLUSION: Consideration of multiple exposures is important in accurately estimating specific effects and in evaluating realistic exposure scenarios.

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.

Epidemiology of unintentional adult injury in a rural population.

BACKGROUND: The purpose of this study was to describe the frequency, characteristics, and risk factors of unintentional adult injury in a rural population. METHODS: We interviewed 1,644 adults representing an all-rural county in Iowa. Analyses used bivariate and multivariable logistic regression. RESULTS: Participants' mean age was 53 years, and 54% were women. Twenty-three percent (n = 380) of participants reported an injury during the past 12 months, of which four fifths were treated. Overexertion (25%) and falls (22%) caused nearly half the injuries. Women with high levels of depression symptoms had 1.57 times (95% confidence interval, 1.05-2.33) the prevalence of injury occurrence as did women with low levels of depression symptoms. Men with a CAGE score of 2 or more had between 0.98 and 2.56 times (according to the range of values of the relevant odds ratio 95% confidence interval) the prevalence of injury episode of men without this exposure. CONCLUSION: The association of injury occurrence with alcohol problems is consistent with prior research, but the increased prevalence of injury associated with high levels of symptoms of depression requires further study and explanation.

Agricultural use of organophosphate pesticides and the risk of non-Hodgkin's lymphoma among male farmers (United States).

OBJECTIVE: Data from three population-based case-control studies conducted in Kansas, Nebraska, Iowa, and Minnesota were pooled to evaluate the relationship between the use of organophosphate pesticides and non-Hodgkin's lymphoma (NHL) among white male farmers. METHODS: The data set included 748 cases of non-Hodgkin's lymphoma and 2236 population-based controls. Telephone or in-person interviews were utilized to obtain information on the use of pesticides. Odds ratios (OR) adjusted for age, state of residence, and respondent status, as well as other pesticide use where appropriate, were estimated by logistic regression. RESULTS: Use of organophosphate pesticides was associated with a statistically significant 50% increased risk of NHL, but direct interviews showed a significantly lower risk (OR = 1.2) than proxy interviews (OR = 3.0). Among direct interviews the risk of small lymphocytic lymphoma increased with diazinon use (OR = 2.8), after adjustment for other pesticide exposures. CONCLUSIONS: Although we found associations between the risk of NHL and several groupings and specific organophosphate pesticides, larger risks from proxy respondents complicate interpretation. Associations, however, between reported use of diazinon and NHL, particularly diffuse and small lymphocytic lymphoma, among subjects providing direct interviews are not easily discounted.

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.

Rural population survey of behavioral and demographic risk factors for loaded firearms.

OBJECTIVES: In the United States, firearm deaths are almost as frequent as motor vehicle deaths. Firearm unintentional and suicide death rates are raised in rural areas. This study examines firearm prevalence and storage practices in three different types of rural households. METHODS: Adults from a stratified random sample of 983 households in a rural Iowa county were interviewed. The chi2 test of independence was used to assess association between loaded, unlocked firearms and seven behavioral and demographic risk factors. RESULTS: Nearly 67% of respondents reported firearms in their households. Nearly 7% of households had a loaded, unlocked gun. Prevalence of firearms at home was higher while prevalence of loaded, unlocked guns was lower than reported in other surveys. Prevalence of loaded, unlocked guns in farm households, 10.5%, was about twice the level in town households, 5.5% (chi2 test, p=0.033). Having taken a gun safety course was associated with more than double the prevalence of a loaded, unlocked gun, 13.5% v 5.1% (chi2 test, p=0.001). The prevalence of loaded, unlocked guns in households with a handgun, 19.3%, was four and one half times higher than in households with a long gun only, 4.2% (chi2 test, p=0.001). Households with someone with a lifetime prevalence of alcohol abuse or dependence were about twice as likely as other households, 13.0% v 6.6% (chi2 test, p=0.004), to report having loaded, unlocked firearms. CONCLUSIONS: Anyone interested in promoting safe storage of firearms in rural homes should consider these observations.

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 injury in rural Iowa: round one of the Keokuk County Rural Health Study.

BACKGROUND: Unintentional injuries represent a major cause of morbidity and mortality in rural communities. This study aimed to determine the distribution of injury risk factors in a rural Iowa community and to identify the rural subgroups at highest risk for injury. METHODS: We reported on 1583 participants, aged > or =25 years, from Round One of the Keokuk County Rural Health Study, a longitudinal panel study of a rural community. The self-reported data were collected during face-to-face interviews. RESULTS: Our data suggested that several risk factors for injury are not uniformly distributed among rural populations. Male farmers were significantly less likely to wear their seatbelts than townspeople or rural nonfarmers. However, farm women were as likely to wear seatbelts as other women. Both male and female farmers were more likely to use all-terrain vehicles than townspeople or rural nonfarmers. In contrast, townspeople were more likely to ride bicycles than either farmers or rural nonfarmers. Townspeople were less likely to have firearms in their homes than either farmers or rural nonfarmers. Farmers were most likely to have fired a gun in the last year. Male farmers aged <65 years were less than half as likely as other men the same age to report a history of alcohol abuse. Binge drinking was equally frequent among farmers, rural nonfarmers, and townspeople. CONCLUSIONS: These differences in risk behavior in a rural county suggest the possibility of targeting specific rural injury prevention interventions at those with the highest risk for dangerous behavior.

Factors that influence African-Americans' willingness to participate in medical research studies.

BACKGROUND: The underrepresentation of African-Americans among medical research participants is receiving considerable attention because of recent government mandates for the inclusion of all racial/ethnic groups in human subject research. Therefore, there is a need to determine factors that influence minority enrollment in medical research studies. METHODS: Between 1998-1999, 91 African-American residents of the Detroit Primary Metropolitan Statistical Area participated in a mail and telephone survey designed to examine impediments to participation in medical research studies. Chi-square tests and multiple logistic regression analyses were used to examine the association between race, issues related to trust in medical researchers, and the willingness to participate in medical research studies. RESULTS: African-American respondents were somewhat less willing to participate if they attributed high importance to the race of the physician when seeking routine medical care, believed that minorities or the poor bear most of the risks of medical research, and, most especially, their knowledge of the Tuskegee Study resulted in less trust in medical researchers. CONCLUSIONS: These data reiterate the need for medical researchers to build trusting relations with African-Americans and to conduct research in an ethical manner. This includes maximizing benefits, reducing risks, and assuring distributive justice to all medical research study participants.

Vaginal ultrasound as an adjunct to cervical digital examination in women at risk of early delivery.

AIM: To study the utility of transvaginal ultrasound (TVU) in women at high risk of preterm delivery. METHODS: Women who were scheduled for frequent digital examinations of the cervix from 16 to 26 weeks of gestation had TVU determinations of cervical length before their clinical examinations. Clinicians were blinded to the TVU results. Therefore, clinical decision-making was independent of the unreported TVU data. The plan was to relate the ultrasound characterization of the cervix to the study's primary endpoint, the need for hospitalization prior to 26 weeks of gestation for: preterm premature rupture of membranes, preterm labor, cerclage placement, or delivery. RESULTS: Seventeen subjects completed the study. All 3 who met the primary endpoint had ultrasound cervical lengths <20 mm on earlier prenatal visits, when digital examinations of the cervix did not detect problems. A 4th woman had ultrasound lengths <20 mm (she delivered at 27(6)/(7) weeks). CONCLUSION: TVU determination of cervical length provides an earlier warning of cervical shortening than does digital examination.

Indoor environmental quality in six commercial office buildings in the midwest United States.

The aims of this study were to characterize physical, mechanical, and environmental factors influencing indoor environmental quality (IEQ) in commercial office buildings; document occupant perceptions and psychosocial attributes; and evaluate relationships among these parameters. Six large office buildings in metropolitan areas were selected in Iowa, Minnesota, and Nebraska. Comprehensive sampling was conducted over one week in each building, during all four seasons. This paper presents the study methods and selected results from the first round of sampling (November 1996 to April 1997). Air flow and recirculation rates were quite variable, with the proportion of outdoor air provided to occupants ranging from 10 to 79 CFM/person. Carbon dioxide, carbon monoxide, and temperature were within ranges anticipated for nonproblem buildings. Relative humidity was low, ranging from 11.7 to 24.0 percent. Indoor geometric mean concentrations of total volatile organic compounds (TVOCs) ranged from 73 to 235 microg/m3. The most prevalent compounds included xylene, toluene, 2-propanol, limonene, and heptane. Geometric mean formaldehyde concentrations ranged from 1.7 to 13.3 microg/m3, and mean acetaldehyde levels ranged from <3.0 to 7.5 microg/m3. Airborne concentrations of culturable bacteria and fungi were low, with no samples exceeding 150 CFU/m3. Total (direct count) bioaerosols were more variable, ranging from 5010 to 10,700 organisms/m3. Geometric mean endotoxin concentrations ranged from 0.5 to 3.0 EU/m3. Respirable particulates (PM10) were low (14 to 36 microg/m3). Noise levels ranged from 48 to 56 dBA, with mean light values ranging from 200 to 420 lux. Environmental parameters were significantly correlated with each other. The prevalence of upper respiratory symptoms (dry eyes, runny nose), central nervous system symptoms (headache, irritability), and musculoskeletal symptoms (pain/stiffness in shoulders/neck) were elevated compared to other studies using similar questionnaires. Importantly, psychosocial factors were significantly related to increased symptoms in females, while environmental factors were more closely correlated with symptoms in males. Endotoxin concentrations were associated with symptoms in both males and females. These data will help to identify and quantify the relative role of factors that contribute to sick building syndrome. The data collected in this study may also be used to evaluate the effectiveness of current building operation practices, and can be used to prioritize allocations of resources for reduction of risk associated with IEQ complaints.

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.

Randomized trial assessing the feasibility and safety of biologic parents as RBC donors for their preterm infants.

BACKGROUND: Most very low birth weight (<1.0 kg) infants receive RBC transfusions. Several reports have demonstrated that RBCs stored up to 42 days can be transfused safely in small volumes to preterm infants to decrease donor exposure without consequent hyperkalemia, acidosis, or other adverse effects. Although biologic parents are likely candidates as donors of blood for their neonates, it has been suggested that their blood may be serologically incompatible with that of their infants. STUDY DESIGN AND METHODS: A two-arm randomized study was conducted to compare the feasibility and immediate safety of two single-donor programs for providing small-volume RBC transfusions to preterm infants: in one arm, infants received RBCs collected from unrelated donors and stored up to 42 days, and in the other arm, RBCs were collected from one of the biologic parents and stored identically. All infants received compatible RBCs that were WBC reduced before storage, stored in AS-3, and gamma-radiated. All transfusions were given uniformly as 15 mL per kg of RBCs transfused over 5 hours, during which time the infants were closely observed for clinical reactions. In addition, laboratory studies were performed shortly before and after each transfusion. RESULTS: A total of 40 preterm infants received 120 RBC transfusions. Biologic parents experienced several donor eligibility problems. However, once enrolled as donors, they were able to supply all RBCs needed by their infants. Significant differences in rates of clinical transfusion reactions and laboratory abnormalities were rare and had no apparent clinical importance, regardless of whether RBCs were donated by biologic parents or unrelated donors. CONCLUSION: A single-donor system, in which AS-3 RBCs were collected either from unrelated blood donors or from biologic parents and then stored up to 42 days, was able to supply small-volume RBC transfusions needed by individual preterm infants without immediate, adverse effects. Because the risk of infectious disease transmission is likely reduced by limiting donor exposure, it is logical to conclude that single-donor programs should increase transfusion safety and that biologic parents should be considered as blood donors for their infants.

Adaptive responses during anemia and its correction in lambs.

There is limited information available on which to base decisions regarding red blood cell (RBC) transfusion treatment in anemic newborn infants. Using a conscious newborn lamb model of progressive anemia, we sought to identify accessible metabolic and cardiovascular measures of hypoxia that might provide guidance in the management of anemic infants. We hypothesized that severe phlebotomy-induced isovolemic anemia and its reversal after RBC transfusion result in a defined pattern of adaptive responses. Anemia was produced over 2 days by serial phlebotomy (with plasma replacement) to Hb levels of 30-40 g/l. During the ensuing 2 days, Hb was restored to pretransfusion baseline levels by repeated RBC transfusion. Area-under-the-curve methodology was utilized for defining the Hb level at which individual study variables demonstrated significant change. Significant reciprocal changes (P < 0.05) of equivalent magnitude were observed during the phlebotomy and transfusion phases for cardiac output, plasma erythropoietin (Epo) concentration, oxygen extraction ratio, oxygen delivery, venous oxygen saturation, and blood lactate concentration. No significant change was observed in resting oxygen consumption. Cardiac output and plasma Epo concentration increased at Hb levels <75 g/l, oxygen delivery and oxygen extraction ratio decreased at Hb levels <60 g/l, and venous oxygen saturation decreased and blood lactate concentration increased at Hb levels <55 g/l. We speculate that plasma Epo and blood lactate concentrations may be useful measures of clinically significant anemia in infants and may indicate when an infant might benefit from a RBC transfusion.

The prevalence of depressive symptoms and risk factors among Iowa and Colorado farmers.

BACKGROUND: Farmers have been previously reported to have higher rates of depression and suicide compared to other occupations. Comparisons of depressive symptoms and risk factors for states should increase understanding of depression in farmers. METHODS: Representative samples of 385 Iowa and 470 Colorado male principal farm operators in the respective state Farm Family Health and Hazard Surveillance projects were evaluated for depressive symptoms by using the CES-D scale. Risk factors were determined by using weighted multiple logistic regression analyses. RESULTS: Iowa farmers were 1.74 times (P < 0.05) more likely to have had depressive symptoms than Colorado farmers. Being unmarried (odds ratio=3.46), having negative life events within the past year [legal problems (4.67), substantial income decline (2.71), loss of something of sentimental value (3.20)], and lower perceived general health status were risk factors (P < 0.05) for depressive symptoms for male Iowa and Colorado farmers. Higher levels of most risk factors for Iowa farmers, almost twice the frequency of substantial income decline, accounted for the majority of the difference in depressive symptoms between Iowa (12.2%) and Colorado (7.4%). CONCLUSIONS: Although Iowa farmers had 1.74 times higher level of depression symptoms than Colorado farmers, this difference was not significant after adjusting for the higher levels of most risk factors for Iowa farmers.