Temporal changes in the nature of disability: US Army soldiers discharged with disability, 1981-2005

Background: We sought to (1) document and describe the relative proportion of disabilities by major type over the study period, (2) describe the population at risk for different types of disability, and (3) document and describe the type of compensation (an indicator of severity) awarded for different types of disability and any temporal changes in these associations. Methods: Time-series, logistic regression analyses, and direct standardization of rates were used to study 108,119 active-duty Army soldiers discharged with permanent disability between 1981 and 2005. Results: Of all disability, 91% is captured within the top five most prevalent types of disability: musculoskeletal (72%, n=77,418), neurological (6%, n=6,896), mental health (5%, n=5,075), cardiovascular system (4%, n=4,429), and respiratory (4%, n=4,202). Musculoskeletal disability rates are increasing rapidly (+2.5% per year); neurological and cardiovascular disability rates are decreasing (-1.3% and -10.0% annually, respectively), and respiratory and mental health disability rates did not change significantly. Demographic risk factors vary by disability type. At greatest risk for musculoskeletal disability were female soldiers, soldiers who were between the ages of 21 and 35 years, white, in lower-to mid-level enlisted ranks with relatively short service tenure, and soldiers without a college education. Compensation awards also varied by disability type: Overall, 77% (n=83,320) received separation with severance pay, 15% (n=16,107) received a permanent disability retirement, and 8% (n=8,692) received separation without benefits. Separation with severance pay was the largest and fastest growing disability disposition for all disabilities and for musculoskeletal disability specifically. Conclusions: Demographic risk factors vary by type of disability and by compensation award. Musculoskeletal disability rates are rapidly increasing as is separation with severance pay-particularly among white, young, lower ranking female soldiers. (C) 2008 Elsevier Inc. All rights reserved.