The Relationship Between Deployment Frequency and Cumulative Duration, and Discharge for Disability Retirement Among Enlisted Active Duty Soldiers and Marines.

BACKGROUND The frequency and duration of deployments associated with increased morbidity is a significant concern for force health protection within the military population. Understanding the association between deployment and disability may provide a clearer understanding of factors adversely affecting U.S. military force readiness. METHODS A case-control analysis was conducted using records on enlisted active duty personnel in the Army and Marine Corps who were evaluated for a musculoskeletal disability and received a final disability disposition between FY 2003 and 2012. The study compared deployment, deployment frequency, and total time deployed in personnel who received musculoskeletal disability retirement to those with a musculoskeletal disability discharge other than retirement. RESULTS For females and males in either service, any deployment was associated with an increased risk of disability retirement (adjusted odds ratios [aOR] [95% confidence intervals (CI)]: males 1.76 [1.65-1.87]; females 1.41 [1.21-1.64]). Furthermore, increasing number of deployments (3+ deployments males aOR [95% CI]: 2.21 [1.92-2.53]) and time spent deployed (24+ months Army Males aOR [95% CI]: 2.07 [1.79-2.40]) significantly increased the odds for disability retirement. CONCLUSION Increasing frequency and duration of military deployments has an increased risk of disability retirement in service members with a musculoskeletal disability. Further research on this relationship is needed in a more representative sample of the U.S. military population.