The tryptophan depletion theory in delirium: not confirmed in elderly hip fracture patients.

Background: The tryptophan depletion theory assumes that low tryptophan levels are present in delirium. These lower levels may be regarded as a biochemical marker for cellular immune activation, which may lead to increased catabolism of tryptophan into kynurenine via stimulation of the enzyme indoleamine 2,3-dioxygenase (IDO) by interferon-γ.

Objective: To compare plasma tryptophan and kynurenine levels, and IDO activity in hospitalized patients with and without delirium.

Cortisol, insulin, and glucose and the risk of delirium in older adults with hip fracture.

Objectives: To determine the relationship between perioperative delirium and cortisol, glucose, and insulin in older adults acutely admitted for hip fracture.

Design: Prospective cohort study.

Setting: Tertiary university center.

The effects of melatonin versus placebo on delirium in hip fracture patients: study protocol of a randomised, placebo-controlled, double blind trial.

Background: With an ageing population, older persons become a larger part of the hospital population. The incidence of delirium is high in this group, and experiencing delirium has major short- and long-term sequelae, which makes prevention crucial. During delirium, a disruption of the sleep-wake cycle is frequently observed.

Cortisol, interleukins and S100B in delirium in the elderly.

In independent studies delirium was associated with higher levels of cortisol, interleukin(IL)s, and S100B. The aim of this study was to simultaneously compare cortisol, IL-6, IL-8, and S100B levels in patients aged 65years and older admitted for hip fracture surgery with and without delirium. Cortisol, IL-6, IL-8, and S100B were assayed in repeated blood samples.