Causes of delirium

Delirium in elderly people usually represents not a specific brain disease but a non-specific sign of acute medical illness. While brain disorders such as stroke and meningitis need to be excluded as causes, this can usually be accomplished rapidly. What is left, and what overwhelmingly gives rise to delirium, is the inventory of illnesses that commonly occur in elderly people. While in theory the list is long, in practice it amounts to comparatively few causes, readily grouped as medications, infections, heart problems and metabolic abnormalities. These problems often occur in combination. These common disorders can be screened for in a cost-effective way before looking for more exotic causes. This contribution argues that the failure to develop focused approaches to the causes of delirium undermines its recognition and effective management, so that demythologizing the cornucopia of causes is essential to promoting care for this common and commonly mismanaged problem.