FREQUENTLY MISSED DIAGNOSIS IN GERIATRIC PSYCHIATRY

The population of the United States is aging rapidly. In the early 1900s about 4% of the population was older than 65. By the year 2000 it is estimated that nearly one quarter of the population will be age 65 or older. 140 The fastestgrowing segment of the population is that over the age of 85, growing at an estimated rate of 135% per year. 140 Life expectancy from birth is about 79 years for women and 75 years for men in the United States. If an individual survives until the age of 75, however, the average life remaining is about 12 years for women and 8 years for men; even those 85 years of age have an average life expectancy of 6 to 8 years. 103 These demographics indicate that most practitioners will treat an increasing number of older patients and that those patients will live longer. The majority of care providers, however, have had little, if any, formal education or training concerning older adults. Medical education, research programs, consensus recommendations, and treatment guidelines tend to neglect this growing population. Even our health care delivery system has evolved primarily to care for younger and middle aged populations, focusing mainly on outpatient clinics or inpatient hospitalizations. Older adults are not just aged versions of young adults. They have unique characteristics and caring for them requires special knowledge. Aging effects every organ system in the body and alters organ function. These changes lead to decreased physical reserve and altered disease presentation. Common illnesses look very different in an 85 year old compared with a 65 year old. Many experts now subdivide geriatric populations into the "young" old (65 to 74), "middle" old (75 to 84), and "old" old (85+) in an attempt further to define and recognize important clinical differences of this heterogeneous group. Pathophysiology and disease presentation in older adults cannot simply be extrapolated from knowledge concerning younger populations. For example, the most common clinical presentation of myocardial infarction (MI) after the age of 80 is diaphoresis, shortness of breath, and mental status changes. Only 20% experience chest pain typical of MI in younger adults. 128 If practitioners depend only on the symptom of chest pain to recognize MI, 80% of MIs in older adults would be missed. Similar examples occur with common psychiatric disorders in the elderly. Unrecognized medical problems often produce psychiatric symptoms in older adults that require medical management rather than psychiatric treatment. Cognitive deficits may not be recognized in early dementia, fluctuating mental status missed in delirium, and major depression overlooked because depressed mood is absent. Missed diagnoses in the elderly can lead to increased morbidity, mortality, decreased comfort, and impaired function.