C-reactive protein levels predict the incidence of delirium and recovery from it

Abstract

SIR—Delirium (acute confusional state, a sudden onset, fluctuating state of cognitive decrement and disordered consciousness) is a very common condition that complicates the hospital treatment of many older people, particularly in the specialties of medicine, orthopaedics, and general and cardiovascular surgery. It is greatly distressing, life-shortening, and associated with longer hospital stays and residual cognitive impairment [1]. No laboratory test exists to assist in the diagnosis of delirium and thus its diagnosis depended only on clinical observations [2] and is often missed even in specialist centres [3]. The most consistent known risk factor is pre-existing dementia, suggesting that delirium is actually a part of the syndrome of dementia itself [4]. Its mechanism is unknown and, although anticholinergic activity has been given precedence as a basis for specific therapeutics for many years, no randomised controlled trials of cholinergic enhancement have been published. A possible neuroinflammatory basis for delirium is also emerging and low levels of insulin-like growth factor I (IGF-I) have recently been found as a risk factor for incident delirium [5].