Some disorders occur almost exclusively in older people. (See also Overview of Aging.) They are sometimes called geriatrics syndromes (geriatrics refers to the medical care of older people).
Other disorders affect people of all ages but may cause different symptoms or complications in older people. The following are some examples:
Underactive thyroid gland (hypothyroidism): Usually, younger people gain weight and feel sluggish. In older people, the first or main symptom may be confusion.
Overactive thyroid gland (hyperthyroidism): Usually, younger people become agitated and lose weight. In contrast, older people may become sleepy, withdrawn, depressed, and confused.
Depression: Usually, younger people become tearful, withdrawn, and noticeably unhappy. Sometimes older people do not seem unhappy. Instead, they become confused, forgetful, and listless, lose interest in their usual activities, or seem lonely.
Heart attack: Usually, younger people have chest pain. Older people may not have chest pain but may have difficulty breathing or abdominal pain. They may sweat profusely, suddenly feel tired, pass out, or become confused.
Abdominal perforation: An organ in the digestive tract, such as the stomach or intestine, occasionally tears (perforates), causing widespread serious infection in the abdominal cavity. Usually, younger people have severe abdominal pain and fever, and the abdomen feels tight. In contrast, older people may have none of these symptoms. Instead, they may become confused or feel very weak.
The confusion that these disorders cause in older people is often mistaken for dementia.
Older people often have more than one disorder at a time. Each disorder may affect the other. For example, depression may make dementia worse, and an infection may make diabetes worse.
However, disorders no longer have the same devastating or incapacitating effects that they once had in older people. Disorders that were once likely to result in death for older people, such as heart attacks, hip fractures, and pneumonia, can often be treated and controlled. With treatment, many people with chronic disorders, such as diabetes, kidney disorders, and coronary artery disease, can remain functional, active, and independent.