Stress and mood
Sustained stress can lead to high levels of circulating cortisol (regarded as one of the more important of the several "stress hormones"). Such levels may result in an allostatic load, which can lead to various physical modifications in the bodys regulatory networks. Effects during pregnancy
During human pregnancy, increased fetal production of cortisol between weeks 30 and 32 initiates production of fetal lung pulmonary surfactant to promote maturation of the lungs. In fetal lambs, glucocorticoids (principally cortisol) increase after about day 130, with lung surfactant increasing greatly, in response, by about day 135, and although lamb fetal cortisol is mostly of maternal origin during the first 122 days, 88% or more is of fetal origin by day 136 of gestation. Although the timing of fetal cortisol concentration elevation in sheep may vary somewhat, it averages about 11.8 days before the onset of labor. In several livestock species (e.g. cattle, sheep, goats, and pigs), the surge of fetal cortisol late in gestation triggers the onset of parturition by removing the progesterone block of cervical dilation and myometrial contraction. The mechanisms yielding this effect on progesterone differ among species. In the sheep, where progesterone sufficient for maintaining pregnancy is produced by the placenta after about day 70 of gestation, the prepartum fetal cortisol surge induces placental enzymatic conversion of progesterone to estrogen. (The elevated level of estrogen stimulates prostaglandin secretion and oxytocin receptor development.) Exposure of fetuses to cortisol during gestation can have a variety of developmental outcomes, including alterations in prenatal and postnatal growth patterns.
Eventually, the term Alzheimers disease was formally adopted in medical nomenclature to describe individuals of all ages with a characteristic common symptom pattern, disease course, and neuropathology.The National Institute of Neurological and Communicative Disorders and Stroke (NINCDS) and the Alzheimers Disease and Related Disorders Association (ADRDA, now known as the Alzheimers Association) established the most commonly used NINCDS-ADRDA Alzheimers Criteria for diagnosis in 1984, extensively updated in 2007. These criteria require that the presence of cognitive impairment, and a suspected dementia syndrome, be confirmed by neuropsychological testing for a clinical diagnosis of possible or probable Alzheimers disease. A histopathologic confirmation including a microscopic examination of brain tissue is required for a definitive diagnosis. Good statistical reliability and validity have been shown between the diagnostic criteria and definitive histopathological confirmation. Society and culture
Social costs
Dementia, and specifically Alzheimers disease, may be among the most costly diseases for societies worldwide. As populations age, these costs will probably increase and become an important social problem and economic burden. Costs associated with AD include direct and indirect medical costs, which vary between countries depending on social care for a person with AD. Direct costs include doctor visits, hospital care, medical treatments, nursing home care, specialized equipment, and household expenses.