A prediction model of military combat and training exposures on VA service-connected disability: a CENC study.

Background: Research has shown that number of and blast-related Traumatic Brain Injuries (TBI) are associated with higher levels of service-connected disability (SCD) among US veterans. This study builds and tests a prediction model of SCD based on combat and training exposures experienced during active military service.Methods: Based on 492 US service member and veteran data collected at four Department of Veterans Affairs (VA) sites, traditional and Machine Learning algorithms were used to identify a best set of predictors and model type for predicting %SCD ≥50, the cut-point that allows for veteran access to 0% co-pay for VA health-care services.Results: The final model of predicting %SCD ≥50 in veterans revealed that the best blast/injury exposure-related predictors while deployed or non-deployed were: 1) number of controlled detonations experienced, 2) total number of blast exposures (including controlled and uncontrolled), and 3) the total number of uncontrolled blast and impact exposures.Conclusions and Relevance: We found that the highest blast/injury exposure predictor of %SCD ≥50 was number of controlled detonations, followed by total blasts, controlled or uncontrolled, and occurring in deployment or non-deployment settings. Further research confirming repetitive controlled blast exposure as a mechanism of chronic brain insult should be considered.

Audiologic characteristics in a sample of recently-separated military Veterans: The Noise Outcomes in Servicemembers Epidemiology Study (NOISE Study).

Military Service Members are often exposed to high levels of occupational noise, solvents, and other exposures that can be damaging to the auditory system. Little is known about hearing loss and how it progresses in Veterans following military service. This epidemiology study is designed to evaluate and monitor a cohort of Veterans for 20 years or more to determine how hearing loss changes over time and how those changes are related to noise exposure and other ototoxic exposures encountered during military service. Data reported here are from baseline assessments of the first 100 study participants (84 males; 16 females; mean age 33.5 years; SD 8.8; range 21-58). Each participant was asked to complete a comprehensive audiologic examination and self-report questionnaires regarding sociodemographic characteristics, noise and solvent exposures, health conditions common among post-deployment Veterans, and the social and emotional consequences of hearing loss. For this relatively young cohort, 29% exhibited hearing loss, defined as average hearing threshold >20 dB HL in the conventional audiometric range. Forty-two percent exhibited hearing loss in the extended-high-frequency audiometric range using the same criterion (average hearing threshold >20 dB HL). Certain factors were found to be associated with poorer hearing in both conventional and extended-high-frequency ranges, including age, type of military branch, years of military service, number of military deployments, noise exposure, tinnitus, and a positive screen for post-traumatic stress disorder. Although the majority of participants had hearing within normal limits, 27% reported a self-perceived mild/moderate hearing handicap and 14% reported a significant handicap. Further research is needed to identify a cause for this discrepancy in audiologic results versus self-report. The information obtained from this longitudinal study could be used in future resource planning with the goal of preventing, as much as possible, the development of hearing loss during military service, and the exacerbation of prevalent hearing loss after military service and over Veterans' lifetimes.

Agricultural injuries among operation household members: RRIS-II 1999.

The purpose of this study was to determine the magnitude and consequences of agricultural injuries, and to reveal potential risk factors among agricultural household members. The Regional Rural Injury Study (RRIS-II) collected injury and exposure data on agricultural households of 16,538 people in Minnesota, Wisconsin, North Dakota, South Dakota, and Nebraska for each six-month period of 1999. Adjusted injury rates, consequences, and potential risk factors were identified through analyses. Selection of variables for multivariate analyses was based on a causal model. Injuries reported here occurred while the individuals were involved in activities associated with their own farm or ranch, unless otherwise stated. Estimates of injury rates and the effects of various exposures were derived by Poisson and logistic regression. These models accounted for correlation within both subject and household, and were adjusted for non-response. The rate of agricultural injury to household members on their own operation was 74.5 injuries per 1,000 persons per year. Differences in rates due to age and gender diminished when rates were calculated according to hours worked. Although only 5% of injured persons required in-patient hospitalization, 28% required emergency department treatment, and 84% required some type of professional health care. Moreover, 47% of all injuries required time off from agricultural work, and 7% required time off from non-agricultural work. In multivariate analyses, decreased risks were associated with Minnesota, and increased risks were identified for those with prior injuries and for males.This study provides a basis for further research on agricultural injuries and their prevention.