Neuropsychiatric aspects of failure to thrive in late life.

Both depression and dementia can lead to failure to thrive (FTT). Depression can lead to FTT by two routes: a direct path related to decreased appetite as a symptom of depression; and an indirect path related to the effect of depression in increasing disability. Depression associated with FTT should usually be treated with antidepressant medication. In Alzheimer's patients with FTT, the thrust of treatment is the identification and treatment of the medical and psychiatric comorbidities and the appropriate titration of environmental supports.