An Aeromedical Review of Sickle-Cell Trait in Army Aviation

Sickle-cell trait (HbAS) is present in approximately 8% of American black recruits and 0.05% of non-black recruits. HbAS has caused major concern in the aviation medical community as a possible causal and latent health-risk factor for aircrewmembers. Concern stems from reports purporting to show in HbAS individuals a causal relation between altitude-induced hypoxia and splenic infarction and between physical exertion at altitude and sudden death. These concerns have been offset by the lack of research establishing such a direct cause-effect relationship. In light of the prevailing controversy a literature review of the aeromedical aspects of HbAS was undertaken.