Hormonal changes clearly influence brain function and certain mental disorders, such as depression, are associated with, and may even result from, disorders of the endocrine system. As normal aging is associated with varying degrees of dysregulation in the endocrine system, this book addresses the hormonal basis of mental disorders in older people, which offers the possibility of new therapeutic approaches in an ever growing aged population.

The first section of the book provides a concise and comprehensive overview of the diverse sites and cellular mechanisms of action of steroid and thyroid hormones in the brain as well as their synthesis in the endocrine organs or in the brain itself. The second section identifies age related changes in the prevailing levels of cortisol, thyroid hormones, and sex steroids (estrogen, progesterone, testosterone, and dehydroepiandrosterone) and assesses the evidence for ascribing a role for these changes in the emergence of common mental disorders. For example, animal and human studies suggest that high corticosteroid concentrations in elderly subgroups are associated with a higher risk of developing cognitive defects; reduced responsiveness of the hypothalamo-pituitary-thyroid axis in aging seems to be related to mood disorders; therapy with estrogen (women) or testosterone (men) may be protective against developing depressive symptoms and estrogen may have beneficial effects on cognition and dementia. Sex differences and, by implication, a role for sex steroid hormones, are also noted in schizophrenia, anxiety disorders, pain perception, immune function, and psychotropic drug metabolism. However, many contributors emphasise the inconsistencies in the scientific literature and the general lack of properly controlled hormone replacement studies in elderly people. Therefore, the view that youthful hormonal profiles will promote healthier aging must remain speculative until more conclusive evidence is available. In its critical approach, this book should be an impetus to such potentially important research and it provides valuable information for clinicians and basic researchers alike in this complex and growing area.