Karshi-Khanabad Surveillance Program (K2SP): Initial Morbidity and All-Cause Mortality Findings.

Abstract

The aim of this study was to evaluate associations between deployment to Karshi-Khanabad (K2) and adverse health outcomes. This is a retrospective cohort study comparing K2 veterans (2001 to 2005) with two matched groups: veterans deployed to Southwest Asia (Operation Enduring Freedom [OEF]-deployed) and non-deployed veterans (OEF-era). Morbidity (through 2022) was identified via Veterans Affairs (VA)/Department of Defense health care databases, and prevalence ratios were estimated using generalized linear models. Mortality (through 2021) was assessed via VA/DoD Mortality Data Repository using standardized mortality ratios and Cox proportional hazards models. Only 2 of the 60 outcomes had elevated prevalence but did not show a pattern suggesting association with K2 deployment. Mortality (hazard ratio: 1.03; 95% confidence interval: 0.88 to 1.22) was not elevated among K2 veterans. Deployment to K2 does not appear to be associated with increased morbidity or mortality at this time. Continued surveillance of this cohort is planned over the next decade.