Functional status can be viewed as a summary measure of the overall impact of health conditions in the context of a patient’s physical and psychosocial environmental. Functional status information is important for planning, monitoring responses to therapy, and for determining prognosis. Functional impairment is common in older adults and has many potential causes, including age-related physiological and cognitive changes, disuse, disease, social factors, and the interplay between any of these. According to the 2007 Centers for Medicare and Medicaid Services, Medicare Current Beneficiary Survey, 29% of patients age 65 years and older had limitations in basic activities of daily living (ADLs: bathing, dressing, eating, transferring, continence, toileting) and 14% had limitations in instrumental ADLs (IADLs; transportation, shopping, cooking, using the telephone, managing money, taking medications, cleaning, laundry). IADLs are activities that are essential for independent living. Subtle or new declines in IADL function may be an early sign of dementia, or other disease, such as Parkinson disease. Loss of ADL or IADL function often signals a worsening disease process or the combined impact of multiple comorbidities. Level of ADL and IADL impairment can usually be determined by self- or proxy report, but should be corroborated when possible. When accurate functional information is essential for planning, direct observation by a physical or occupational therapist can be invaluable.
For highly functional independent elders, standard functional screening measures will not capture subtle functional impairments. One technique that may be useful for these elders is to identify and regularly query about a target activity, such as playing bridge, golf, or fishing that the patient enjoys and regularly participates in (advanced ADLs). Although many of these activities reflect patient preferences that may change over time, if the patient begins to drop the activity, it may indicate an early impairment, such as dementia, incontinence, or worsening vision or hearing loss.
Functional status should be assessed initially and periodically thereafter, particularly after hospitalization, severe illness, or after the loss of a spouse or caregiver. Unexpected changes in functional status should prompt a comprehensive evaluation. If no reversible cause of functional decline is found after a reasonable medical search, the clinician should focus on supportive services, and when necessary, placement in a different living setting. For more information about functional ability and assessment in older persons, refer to Chapter 2, “Consideration of Function & Functional Decline.”