Depression in early-onset Alzheimer's disease: clinical and neuroendocrine correlates

Hypothalamic-pituitary-adrenal system function in patients with Alzheimer's disease

The neuropathologic hallmarks of Alzheimer's disease (AD) are very prominent in the hippocampus, a brain site which is pivotal for the regulation of the hypothalamic-pituitary-adrenal (HPA) system. Thus, the combined dexamethasone-suppression/CRH-stimulation-test outcome in patients with AD was compared to that of healthy elderly controls to assess--with a more refined neuroendocrine challenge procedure--HPA function in AD. Cortisol secretion after dexamethasone (DEX) pretreatment and before CRH was increased in Alzheimer's patients and 21% of this group were DST-nonsuppressors. None of the healthy control subjects escaped DEX-induced suppression of cortisol. However, after additional CRH administration, AD patients released significantly less cortisol and ACTH than the control subjects. No correlations were found between any of the endocrine parameters and degree of severity of dementia. It is concluded that the DST part of the DEX/CRH test better reflects glucocorticoid feedback disturbances, probably at a suprapituitary level. The CRH part of the DEX/CRH-test outcome might indicate the loss of endogenous CRH-Arginine-Vasopressin (AVP) synergism of the HPA system of these patients.

Primary or depressive dementia: mental status screening

In the course of interviewing a patient, several aspects of everyday functioning must be covered to provide a range of observations necessary to suggest a provisional diagnosis. First organized by Adolf Meyer, the mental status examination consists of several techniques which, in recent times, have been shortened, structured and standardized to cover maximal ground in minimal time. In this article, the most popular scales are reviewed psychometrically for their capacity to detect, as first-stage instruments, cognitive impairment suggestive of primary dementia in the context of varying prevalence rates and confounding factors like sensory impairments, sociodemographics and depressive states. Several of the measures are found adequate in some respects though not in others, but all of the better ones, when used as front line implements during clinical intake, regularly improve detection over base rates. An analytical method modelled on ROC procedures is then described contrasting two of them before newer instruments are considered which aim to improve sensitivity at relatively little cost to specificity.