Craig Zwerling

Bio: Craig Zwerling is an academic researcher from University of Iowa. The author has contributed to research in topics: Poison control & Injury prevention. The author has an hindex of 10, co-authored 14 publications receiving 506 citations.

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

Abstract: 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.

The prevalence of depressive symptoms and risk factors among Iowa and Colorado Farmers

Abstract: 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. Am. J. Ind. Med. 37:382–389, 2000. © 2000 Wiley-Liss, Inc.

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

Abstract: 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.

The injury fact book

Abstract: This book includes detailed information on many of the factors surrounding injuries--the man-made systems and products involved, the groups at greatest risk, and effective ways to protect people from injuries. The circumstances under which injuries occur, the etiologic agents, and the characteristics of the people involved are examined. Chapter 2 summarizes the importance of injuries in relation to other prominent health problems. Subsequent chapters describe injury mortality and, in cases where good population-based studies are available, nonfatal injuries. The analyses in Chapters 3-15 are primarily of injury deaths during 1977-1979, the most recent years for which detailed mortality data were available in mid-1983 for deaths other than those related to motor vehicles. Most of these data were collected by the U.S. Department of Health and Human Services, National Center for Health Statistics (NCHS). Chapters 16-20 summarize data on deaths from motor vehicle-related injuries. Most of these detailed data were obtained from the U.S. Department of Transportation, National Highway Traffic Safety Administration (NHTSA). Data from the 1980 census provided denominators for the rates throughout the book, except for trendline calculations which were based on interpolations between census years. The purpose of this book is to improve understanding of the nature and magnitude of the injury problem in the United States. Although it includes some discussion of ameliorative approaches, there is no comprehensive coverage of injury research, theory, or prevention, since these have been comprehensively discussed elsewhere. This book is a thorough documentation of the injury problem. Most of the information presented is new, the product of analyses not previously published in any form.

Cranio-maxillofacial trauma: a 10 year review of 9,543 cases with 21,067 injuries.

Abstract: Introduction: Cranio-maxillofacial trauma management requires pertinent documentation. Using a large computerized database, injury surveillance and research data describe the whole spectrum of injuries. The goal of this study was to assess the effect of the five main causes of accidents resulting in facial injury on the severity of cranio-maxillofacial trauma. Patients and Methods: During a period of 10 years (1991-2000) 9543 patients were admitted to the Department of Oral and Maxillofacial Surgery, University Hospital of Innsbruck with cranio-maxillofacial trauma. Data of patients were prospectively recorded including cause of injury, age and gender, type of injury, injury mechanisms, location and frequency of soft tissue injuries, dentoalveolar trauma, facial bone fractures and concomitant injuries. Statistical analyses performed included descriptive analysis, chi square test, Fisher's exact test, and Mann-Whitney's U test. This was followed by logistic regression analyses for the three injury types to determine the impact of the five main causes on the type of injury at different ages in facial trauma patients. Results: Five major categories/mechanisms of injury existed: in 3613 (38%) cases it was activity of daily life, in 2991 (31%) sports, 1170 (12%) violence, in 1116 (12%) traffic accidents, in 504 (5%) work accidents and in 149 (2%) other causes. A total of 3578 patients (37.5%) had 7061 facial bone fractures, 4763 patients (49.9%) suffered from 6237 dentoalveolar, and 5968 patients (62.5%) from 7769 soft tissue injuries. Gender distribution showed an overall male-to-female ratio of 2.1 to 1 and the mean age was 25.8±19.9 years; but both varied greatly depending on the injury mechanism (facial bone fractures: 35.4±19.5 years, higher risk for males; soft tissue injuries: 28.7±20.5, no gender preference; dentoalveolar trauma: 18±15.6, elevated risk for females). For patients sustaining facial trauma, logistic regression analyses revealed increased risks for facial bone fractures (225%), soft tissue lesions (58%) in patients involved in traffic accidents, and dental trauma (49%) during activities of daily life and play accidents. When compared with other causes, the probability of suffering soft tissue injuries and dental trauma, but not facial bone fractures, is higher in sports-related accidents, 12 and 16%, respectively. Conclusion: This study differentiated between injury mechanisms in cranio-maxillofacial trauma. The specially trained surgeons treating cranio-maxillofacial trauma are the primary source of information for the public and legislators on implementing preventive measures for high-risk activities. In facial trauma, older persons are prone to bone fractures (increase of 4.4%/year of age) and soft tissue injuries (increase of 2%/year of age) while younger persons are more susceptible to dentoalveolar trauma (decrease of 4.5%/year of age).

Health effects of chronic pesticide exposure: cancer and neurotoxicity.

Abstract: Pesticides are widely used in agricultural and other settings, resulting in continuing human exposure. Epidemiologic studies indicate that, despite premarket animal testing, current exposures are associated with risks to human health. In this review, we describe the routes of pesticide exposures occurring today, and summarize and evaluate the epidemiologic studies of pesticide-related carcinogenicity and neurotoxicity in adults. Better understanding of the patterns of exposure, the underlying variability within the human population, and the links between the animal toxicology data and human health effects will improve the evaluation of the risks to human health posed by pesticides. Improving epidemiology studies and integrating this information with toxicology data will allow the human health risks of pesticide exposure to be more accurately judged by public health policy makers.

Workplace Violence against Health Care Workers in the United States.

Abstract: Violence against health care professionals in the workplace is underreported and understudied. Additional data are needed to understand steps that might be taken to reduce the risk.