But what is functional status? Ironically, despite the importance of functional status to Geriatrics, defining what functional status is, or how it should be assessed is not so obvious. In practice, most functional status evaluations focus on assessing whether or not patients can do specific tasks important to day to day life. For example, can you do basic activities of daily living such as take a bath or shower, get dressed, or walk across a room with assistance? Can you do housework, manage your finances, and manage your medicines?
But there is increasing interest in more holistic views of functional status. These views focus not just on tasks you can or can't do, but on how well you live despite of functional problems. One of the most interesting of these new ways of thinking about functional status is Life Space. Life Space considers the size of the person's world. Are you confined to your home, or you able to get out to town, or even out of town?
Consider the following example:
Older person A is independent in all basic activities of daily living and can walk moderate distances. But she is depressed and has limited social support and seldom gets out of her residence. Older person B depends on the help of others for basic activities of daily life such as bathing. She can only walk a few steps without assistance. But she has a supportive family that helps with basic activities. With her motorized scooter, she makes it to church and her weekly bridge game. Her family helps help her get out of town on their family vacations.
Who is more disabled? Classical measures of functional status would say patient B. But a Life Space approach recognizes Patient B as doing much better than patient A.
A recent study in the Journal of the American Geriatrics Society from Dr. Patricia Boyle provides important evidence supporting the assessment of life space by showing that it is strongly associated with mortality. They followed over 1400 elders for up to 8 years. Those who had wide life spaces had much better survival than those who had a constricted life space. For example, among those able to get out beyond their home town, 5 year mortality was about 13%. However, among those restricted to the confines of their home, 5 year mortality was about 24%. Life space was associated with mortality even after accounting for classic measures of disability such as difficulty with basic activities of daily living. This means that life space is telling us something important, beyond the tasks an older person can or can not do.
We need more focus on functional status measures that tells us how well our patients live, rather than simply what tasks than can or can not do. We need to incorporate more measures of life space into Geriatric practice and research. I wonder if more attention to these measures will improve practice by helping us think not just about an elder's degree of disability, but how we palliate their disability by helping them live well despite disability.
by: [Ken Covinsky]