Pathoplastic Effects of Age
Age appears to influence psychopathology in three ways (Table 8.1). A few mental disorders appear almost to be age-specific and not to occur outside a certain age range. Feeding disorder of infancy or early childhood (failure to thrive) is a disturbance restricted to the first several years of life because of a child’s total dependence on caregivers for food during this time. Dementia of the Alzheimer’s type is much more common after the age of 65 years; few cases develop before age 50 years.
More commonly, disorders that may occur at virtually any age have an usual onset at certain stages in life. Mental retardation, learning disorders, disruptive behavior disorders and elimination disorders, among others, usually have their onset and are first diagnosed during childhood. The median age at onset for
the first psychotic episode of schizophrenia is in the early to mid-twenties for men and in the late twenties for women (American Psychiatric Association, 2000).
Most mental disorders can occur at various times in life’s stages. Some of these are expressed differently depending on age. For example, although the core symptoms of major depression are the same regardless of a person’s age, in children somatic symptoms, irritable mood and social withdrawal may be espe-cially common. In depressed elderly persons, cognitive symp-toms such as memory loss, disorientation and distractibility may predominate.