CHAPTER
2
Implications of an Aging
Population for Rehabilitation:
Demography, Mortality, and Morbidity
of Older Adults
Andrew A. Guccione, PT, PhD, DPT, FAPTA
What are the implications of an increase in the number
of older persons in American society, particularly as it
affects rehabilitation specialists such as physical therapists? Some have portrayed the “graying” of America
during the past 60 years as a social problem of vast numbers of resource-guzzling older adults who threaten
to strip the health care system of its scarce resources.
Others have portrayed this same group as a rich resource
to their families and their communities: a group still very
much engaged in life as healthy, active older adults. Is
it possible that these two contrasting representations
of America’s older persons refer to the same set of
individuals?
The purpose of this chapter is to review the sociodemographic characteristics of older adults in American
society, then relate these factors to mortality and
morbidity in this population. In doing so, we shall
find that conflicting portrayals of older persons as
active and healthy, or as sick and frail, are neither incorrect nor contradictory, but more appropriately
applied to only some segments of a heterogeneous
population.
Although physical therapists implement interventions in a plan of care designed for individual patients
or clients, each of us has physical, psychological, and
social characteristics by which we can be categorized
into groups. Knowing that individuals with certain
characteristics—for example, being a particular age or
sex—are more likely to experience a particular health
problem can assist physical therapists in anticipating
some clinical presentations, placing an individual’s
progress in perspective, and even sometimes altering
outcomes through preventive measures. It is also useful
to know the prevalence of a particular condition
(i.e., the number of cases of that condition in a population) and its incidence (the number of new cases of a
16
condition in a population within a specified time period). Taken beyond examination of a single person,
physical therapists can use this information to plan
and develop services that will meet the needs of an
aging society whose members span a continuum across
health, infirmity, and death.
There is one critical caveat to any of the inferences
about aging or older persons that may be drawn from
the data below. Much of what we in the United States
know in gerontology and geriatrics has been derived
from two specific cohorts. The first cohort was born
near the end of the 19th century, many of them impoverished child immigrants or born into families recently
arrived in America. Thus the initial emergence of
gerontological research in the 1970s is based largely on
these individuals whose early health and vitality into
adulthood were determined long before the medical
advances and economic prosperity that marked the
“American Century.” Their children comprise the second cohort, whose experiences define our current-day
understanding of aging. Geriatric and gerontological
research in this group is also contextually situated in
the defining events of the first half of the 20th century:
two world wars and the Great Depression. Thus, whenever we choose to explicate aging and the status of
older adults, be it their physical health or social wellbeing, we must also appreciate that what we understand is based on what either has been or is currently
the case, not necessarily what will be the norm in the
future. As the adults of the post–World War II “baby
boom” begin to retire in 2011, we can expect that gerontological theories and geriatric practice—geriatric
physical therapy included—will change markedly by
mid–21st century to accommodate new findings that
emerge from scientific study of this third and markedly
distinct cohort.
Copyright © 2012, 2000, 1993 by Mosby, Inc., an affiliate of Elsevier Inc.
CHAPTER 2 Implications of an Aging Population for Rehabilitation
SUCCESSFUL VS. OPTIMAL AGING
“Successful aging” was a multidimensional concept first
articulated in the late 1980s and further elaborated in
the 1990s to distinguish between individuals with the
characteristics of usual aging and those adults who had
managed successful aging. The concept of successful aging encompassed three elements: avoiding disease and
disability, maintaining high physical and cognitive function, and sustaining engagement in social and productive
activities.1,2 The research that supported the concept
suggested that biological orientations to aging in gerontological research were biased toward “usual” or “average” aging but ignored the equally important long-term
effects of diet, exercise, and lifestyle that characterized
the successful aging of many who had escaped the usual
decline and disability of average aging. Physical therapists can assist the promotion of successful aging by
encouraging modification of some extrinsic factors,
particularly in teenagers and young adults, which lead
to less disease and disability in the later years. For those
with disease and disability, the physical therapist should
work within the concept of “optimal aging,” which
allows an individual to achieve life satisfaction in multiple domains—physical, psychological, and social—
despite the presence of disabling medical conditions.
Physical therapists can promote optimal aging by reducing the disabling effects of disease and stopping a vicious
cycle of “disease–disability–new incident disease” to
maintain quality of life.
1900. In 1940 they were 6.9% of the population, and
by 1950, they were equal to 8.2%. Although they represented just fewer than 10% of the population in 1970,
they currently account for almost 13% of the U.S.
population.4 Individuals born between the years 1946
and 1964 are frequently referred to as the “Baby Boomers” and will be responsible for a sharp rise in the number of older people between 2010 and 2030, when the
older population is predicted to account for nearly 20%
of the total U.S. population.4 Individuals older than age
85 years currently represent just under 10% of people
older than age 65 years (5.3 million people in 2006),
but their representation within the general populace is
likely to quadruple by 2050 (Figure 2-1).4 The number
of individuals older than 100 also continues to increase,
even though the actual proportion of the total population (1 of every 10,000) is relatively small.5
Two concurrent factors that have affected the increase
in the proportion of aged in our society are a declining
birthrate and a declining death rate. With fewer births
overall and more survivors at older ages, the age structure of the population changes from a triangular shape,
with a larger number of younger individuals at the base,
to a more rectangular distribution of the population by
age, with a trend over time for a larger proportion of
older individuals at the top, especially among the oldest
old.6 In 1990 and 2000, the shape of the age pyramid
shows remnants of the traditional triangular structure as
well as the beginning “rectangularization” (Figure 2-2).
DEMOGRAPHY
Number of people age 65 and older, by age group,
selected years 1900-2006 and projected 2010-2050
Defining “Older” Adult
100
90
80
70
Millions
The first gerontological question is how a particular segment of a population comes to be categorized as “older”?
The chronological criterion that is presently used for
identifying the older adult in America is strictly arbitrary
and usually has been set at age 65 years. However, the
onset of some of the “geriatric” health problems of older
individuals may occur as soon as they enter their early
50s, and, as detailed elsewhere, “older” athletes may be
only in their 40s. As the mean age of the population increases and more individuals live into their ninth and
tenth decades, we can expect that our notion of who is
“older” will change.
60
50
40
65 and older
30
20
85 and older
10
0
1900
1920
1940
1960
1980
2000
2006
Population Estimates and Age Structure
The number of Americans age 65 years and older continues to grow at an unprecedented rate. In 2007 the
best available estimate of persons age 65 years or older
was 37.3 million,3 reflecting the major changes in the
population structure of the United States in the past
century. Individuals who had reached their 65th birthday accounted for only 4% of the total population in
17
2020
2040
Projected
Note: Data for 2010-2050 are projections of the population.
Reference population: These data refer to the resident population.
Source: U.S. Census Bureau, Decennial Census, Population
Estimates and Projections.
FIGURE 2-1 Growth of the population age 65 years and older,
past and projected, with projected growth of adults age 85 years
and older to midcentury. (From Federal Interagency Forum on
Aging-Related Statistics: Older Americans 2008: key indicators of
well-being. Washington, DC: U.S. Government Printing Office,
March 2008.)
CHAPTER 2 Implications of an Aging Population for Rehabilitation
18
(NP-P2) Projected Resident Population of the
United States as of July 1, 2000, Middle Series.
100 and
over
95 to 99
90 to 94
85 to 89
80 to 84
75 to 79
70 to 74
65 to 69
60 to 64
55 to 59
50 to 54
45 to 49
40 to 44
35 to 39
30 to 34
25 to 29
20 to 24
15 to 19
10 to 14
5 to 9
Under 5
Age
Age
(NP-P1) Resident Population of the United States as of July 1, 1990.
100 and
over
95 to 99
90 to 94
85 to 89
80 to 84
75 to 79
70 to 74
65 to 69
60 to 64
55 to 59
50 to 54
45 to 49
40 to 44
35 to 39
30 to 34
25 to 29
20 to 24
15 to 19
10 to 14
5 to 9
Under 5
5 4.5 4 3.5 3 2.5 2 1.5 1 .5 .0 .5 1 1.5 2 2.5 3 3.5 4 4.5 5
5 4.5 4 3.5 3 2.5 2 1.5 1 .5 .0 .5 1 1.5 2 2.5 3 3.5 4 4.5 5
Male
Percent
Female
Male
Age
Age
5 4.5 4 3.5 3 2.5 2 1.5 1 .5 .0 .5 1 1.5 2 2.5 3 3.5 4 4.5 5
100 and
over
95 to 99
90 to 94
85 to 89
80 to 84
75 to 79
70 to 74
65 to 69
60 to 64
55 to 59
50 to 54
45 to 49
40 to 44
35 to 39
30 to 34
25 to 29
20 to 24
15 to 19
10 to 14
5 to 9
Under 5
5 4.5 4 3.5 3 2.5 2 1.5 1 .5 .0 .5 1 1.5 2 2.5 3 3.5 4 4.5 5
Percent
Male
Female
(NP-P4) Projected Resident Population of the
United States as of July 1, 2050, Middle Series.
(NP-P3) Projected Resident Population of the
United States as of July 1, 2025, Middle Series.
100 and
over
95 to 99
90 to 94
85 to 89
80 to 84
75 to 79
70 to 74
65 to 69
60 to 64
55 to 59
50 to 54
45 to 49
40 to 44
35 to 39
30 to 34
25 to 29
20 to 24
15 to 19
10 to 14
5 to 9
Under 5
Percent
Percent
Female
Male
Female
FIGURE 2-2 Change in the population age structure by age and sex from 1990 to 2050 showing shifts in proportions of younger individu-
als to older individuals. (Source: National Estimates Program, Population Division, U.S. Census Bureau, Washington, DC, 20233. From U.S.
Census Bureau: U.S. population projects: population pyramids [website]: http://www.census.gov/population/www/projections/natchart.html;
Accessed February 27, 2010.)
By 2050, the age structure “pyramid” is relatively rectangular except among the older age groups.
Life Expectancy
In 2007, the median age of the total population of the
United States was 36.4 years, whereas the median age of
individuals 65 years and older was 74.8 years.3 In the
first half of the 20th century, mortality declined primarily as a result of advances in health at birth and younger
ages, especially infant mortality. However, by 2000 the
changes in life expectancy were primarily the result of
reduced mortality at older ages, not the least of which
was the dramatic increase in the number of adults who
lived to age 85 years.6 In 1900, a person who lived until
age 65 years might expect another 12 years of life.
Additional life expectancy for individuals age 65 years in
2000 had grown to 18 years. However, female life expectancy continues to outpace male life expectancy, despite
gains made for both sexes, although the gap has begun
to decrease. Racial differences in life expectancy have
also been demonstrated, as white women generally live
CHAPTER 2 Implications of an Aging Population for Rehabilitation
the longest, whereas black women and white men live
about the same and black men have the lowest survivorship.6 There has been a long-standing controversy in the
literature regarding whether there is a racial crossover at
the oldest ages, where black survivorship may improve.
Some have argued that the phenomenon is actually a
statistical artifact of misreporting and data inconsistencies, or not accounting for confounding variables; other
researchers have drawn conclusions about “survival of
the fittest,” arguing that individuals who surmount racial, socioeconomic, and health disadvantages early in
life represent the most “fit” to survive into old age.
Race and Ethnicity
Racial and nonwhite ethnic minorities are currently
underrepresented among the nation’s older adults relative
to the distribution of these subgroups in the general population. In 2006, approximately 81% of the population age
65 years and older was non-Hispanic white, whereas
blacks accounted for 9%, Asians 3%, and Hispanics of
any race 6%.4 Hispanic representation in the older population has the fastest overall growth rate of any subgroup,
likely to surpass the black subpopulation of older adults
by 2028, and anticipated to be 15 million in 2050, or
nearly eight times as large as it was in 2005.4 More recent
immigrations in the 1990s of peoples from Southeast
Asia will likely add to the relatively small number (about
1 million) of older Asians in the United States to a projected 7 million by 2050.4 Clearly, the geriatric physical
therapist must recognize that the older adult of the future,
especially those who will be considered the “oldest old,”
will be more racially and culturally diverse than those
patients currently served, and culturally competent care
will literally require a global appreciation of diversity.
Sex Distribution and Marital Status
Simply put, there is a marked sex differential in mortality, and a number of social and life factors beyond biologic predisposition may lead to shorter lives for men
overall.6,7 Married people have a lower mortality at all
ages than their unmarried peers, and married men appear to derive a greater survival advantage than married
women.6 However, because women typically live longer
than men, the problems of America’s older adults are
largely the problems of women, of whom fewer will have
a living spouse at the age of 65 years and older in contrast to their male counterparts (Figure 2-3).8 Older men
are more likely to be married than older women and
married men are generally older than their wives, who
have a greater life expectancy by virtue of their sex
across all racial and ethnic groups.6 Women age 65 years
and older are three times more likely to be widowed as
comparably aged men, with the proportion growing
with each decade of aging.3 There have been many theories proposed to explain the salutary effects of marriage
19
on longevity, generally focusing on social support and
shared resources. However, like most social institutions,
marriage or partnered relationships defy easy characterizations, suggesting that one must look at the specific
attributes of a particular relationship before drawing
conclusions.
In addition to the caregiving burdens and socioeconomic implications of being partnered, loss of a significant
other brings its own set of psychosocial challenges to the
individual in contemporary society. Any individual whose
identity is linked to being a couple or part of a long-term
relationship may experience a severe disruption of social
roles when left alone. This disruption complicates the
search for self-validation through the recognition, esteem,
and affection of another that may have been present in a
marital or partnered relationship.
Living Arrangements
In 2000, 28% of the population age 65 years and older
lived alone,9 noting that older non-Hispanic white
women and black women were more likely to live alone
than other racial or ethnic groups.4 Older black, Asian,
and Hispanic women are more likely than non-Hispanic
white women to live with nonspousal relatives.4 When
older adults need assistance in basic and instrumental
activities of daily living (ADLs), spouses and children
often provide the majority of help. Decline in functional
abilities strongly predicts the likelihood that an older
adult living alone will seek other arrangements.
Nursing home utilization has changed since the
mid-1980s, especially with respect to racial and ethnic
diversity.10 Many more of these individuals now have
short-term admissions and return to their premorbid
living arrangements compared with 20 years ago.10
In 2004, older adults in nursing homes were predominately female; age 75 years and older (82%); white, nonHispanic, and not married.11
Family Roles and Relationships. Despite many social
advances for younger generations of women, the degree
to which female older adults are still bound by society
to traditional roles such as homemaking and caretaking
should not be underestimated. Furthermore, an older
woman is more likely to live alone when compared to
a male counterpart and must continue to function independently, whatever her level of physical function.
Women are therefore more likely than men to report
disability with respect to social roles. The relative unavailability of assistance with home chores in comparison with other social support services may be a subtle
discrimination against older women, although the level
of unmet need in this area is not well documented. These
home services can often be the essential element in allowing an older adult to remain living independently at
home when functional abilities are compromised. Physical therapists will need to continue working with other
health professionals to advocate for access to a wide
CHAPTER 2 Implications of an Aging Population for Rehabilitation
20
Marital status of the population age 65 and older, by age group and sex, 2007
65-74
75-84
85 and older
Men
Women
100
100
90
90
78
80
80
76
74
70
70
60
60
Percent
Percent
60
50
40
57
52
50
40
38
34
30
30
20
10
0
20
17
10
4 4 3
Never
married
6
2
8
Widowed
15
13
10
0
Divorced
26
Married
4 3 4
Never
married
7
4
Divorced
Widowed
Married
Note: Married includes married, spouse present; married, spouse absent; and separated.
Reference population: These data refer to the civilian noninstitutionalized population.
Source: U.S. Census Bureau, Current Population Survey, Annual Social and Economic Supplement.
FIGURE 2-3 Marital status by age and sex of adults age 65 years and older. (From Federal Interagency Forum on Aging-Related Statistics:
Older Americans 2008: key indicators of well-being. Washington, DC: U.S. Government Printing Office, March 2008.)
range of services that support the highest level of independent living for the aged.
Although findings from a number of studies during
the past 20 years have been treated as “common wisdom” about families and aging, the simple fact is that
the magnitude of variation in “family” as a social construct is very great and cannot easily be generalized
into evidence-based statements about the nature of
families, the influence of ethnicity, or gender-specific
roles in caring for older family members. Fertility rates
and immigration patterns also influence the proportion
of family members able to support aging parents.6
Older adults who do live with family can often find
themselves in multigenerational families, growing old
with their children. Spouses are the most likely individuals to care for their partners in old age and sickness. When a spouse is unable or unavailable to provide
assistance, it is not easily determined who will do what
for an aging parent in need. The actual provision of
direct care to older parents has traditionally been described as “women’s work,” which is as much a function of traditional social mores as a lack of evidence to
the contrary. Research has not elucidated the role
of men in caring for older parents as investigators
have often assumed that the responsibility of caregiving
falls to daughters and daughters-in-law, often to the
exclusion of men as subjects in many studies. Recommendations that increase the tasks of caregiving among
selected family members (e.g., assisting with a home
exercise program) may be perceived as either a burden
or as an opportunity12,13; thus evaluation of caregiving
impact of rehabilitation interventions may be required.
Many stereotypes exist about different racial and
ethnic groups, but the data do not support a facile conclusion that one group is more “predisposed” to offer
assistance. Physical therapists must evaluate each family situation for its unique characteristics.
The societal roles of grandparenting also continue to
evolve. Increased longevity increases the amount of one’s
life that might be spent being a grandparent. It is not
unusual for an aging individual to witness a grandchild’s
movement through the life course from birth up to the
grandchild’s adulthood. Healthy older adults still provide substantial financial and emotional support to their
children. Many grandparents find themselves taking on
additional babysitting and child-rearing responsibilities.
Therefore, an examination and evaluation of an older
person’s functional abilities in this social context might
need to consider whether a grandparent has the dexterity
to change a diaper, the strength to lift a toddler, and
the stamina to walk young children home from the
school bus.
CHAPTER 2 Implications of an Aging Population for Rehabilitation
21
100
The tendency to regard older adults as a homogeneous
group biases any understanding of their economic status.
The heterogeneity of this population group is perhaps
best illustrated by considering who is financially well-off
and who is economically disadvantaged among older
adults. Overall, the entrance of the youngest stratum of
older adults, who benefit from private and workers’ pension programs, has improved the economic well-being of
older adults as a whole, as the proportion of older adults
living in poverty has shrunk from 35% in 1959 to 9%
in 2006 (Figure 2-4).4 In comparison with poverty
among children younger than age 18 years, people age
65 years and older have experienced a relatively steady
decline in poverty.4 These group figures, however,
do obscure the realities of poverty among older people;
poverty increases with age; women are more often in
poverty than men; and older Hispanics and older blacks
experience greater economic deprivation than nonHispanic whites.4 Furthermore, although older adults
may be less likely to enter into poverty than individuals
younger than age 18 years, people age 65 years and
older who do enter poverty are less likely to transition
out than their younger counterparts.6 Housing expenditures account for about 33% of expenses, whereas
health care and food each account for about 13%.4
Although expenditures for housing, food, and transportation remain relatively constant for noninstitutionalized
older adults, health care expenses continue to rise after
age 65 years (Figure 2-5).
90
19
20
20
19
Other
13
13
13
13
Food
32
34
32
36
Housing
18
16
17
14
Transportation
13
11
16
Healthcare
5
7
80
70
60
Percent
Economic Status
50
40
30
20
7
10
0
12
55-64
65 and
older
65-74
Personal insurance
4
75 and and pensions
older
Note: Other expenditures include apparel, personal care, entertainment,
reading, education, alcohol, tobacco, cash contribtions, and miscellaneous
expenditures.
Reference population: These data refer to the resident noninstiutionalized
population.
Source: Bureau of Labor Statistics, Consumer Expenditure Survey.
FIGURE 2-5 Total household expenditures by category and
age group. (From Federal Interagency Forum on Aging-Related
Statistics: Older Americans 2008: key indicators of well-being.
Washington, DC: U.S. Government Printing Office, March 2008.)
MORTALITY
Causes of Death
100
Poverty rate of the population, by age group, 1959-2006
90
80
Percent
70
60
50
40
30
65 and older
Under 18
20
10
18-64
0
1959 1964 1969 1974 1979 1984 1989 1994 1999 2004
2006
Data are not available from 1960 to 1965 for the 18 to 64 and 65 and
older age groups.
Reference population: These data refer to the civilian noninstitutionalized
population.
Source: U.S. Census Bureau, Current Population Survey, Annual Social and
Economic Supplement, 1960-2007.
FIGURE 2-4 Poverty rates by age group. (From Federal Interagency Forum on Aging-Related Statistics: Older Americans 2008:
key indicators of well-being. Washington, DC: U.S. Government
Printing Office, March 2008.)
The five most common causes of death for all individuals age 65 years or older are heart diseases, malignant
neoplasms, cerebrovascular disease, chronic lower respiratory diseases, and pneumonia and influenza.4,6
Despite its position as the leading cause of death, ageadjusted death rates in the United States from heart
disease and stroke mortality have declined remarkably
in the past 30 years, most likely because of improvements in the detection and treatment of hypertension as
well as improvements in emergency and critical care.4
However, age-adjusted death rates for both diabetes and
respiratory diseases increased markedly in the same period. Given the role of exercise in the primary and secondary prevention as well as rehabilitation of all of
these conditions, physical therapists are able to make a
major contribution to the well-being of the geriatric
population.
Active Life Expectancy
Adults who survive to age 65 years can expect to live
almost 19 years longer, which is about 7 years longer
than what would have been expected in 1900.4 Although
CHAPTER 2 Implications of an Aging Population for Rehabilitation
gains in overall life expectancy are important indicators
of a nation’s well-being, active life expectancy, that is,
the years spent without a major infirmity or disabling
condition, may provide more meaningful information
for health professionals. More accessible health care,
improved understanding of genetic predisposition, and
preventive behaviors such as increased physical activity
and balanced nutrition have all contributed to more
years spent in better health. Although medical advances
have improved the survivorship of individuals with multiple impairments in old age, the data support the notion
that each successive generation of older adults enjoys a
slightly greater active life expectancy prior to entering
permanent functional decline.4,6
MORBIDITY
Prevalent Chronic Conditions
The proportion of older adults at any age without any
chronic conditions is small. About 80% have at least one
chronic condition and 50% have two or more.6 Among
these, arthritis is the most prevalent self-reported condition causing an activity limitation. Hypertension, heart
disease, stroke, diabetes, hearing and vision impairments, and fractures also take their toll on activity.4,6
Chronic conditions are not randomly dispersed throughout the population (Figure 2-6). Arthritis is more common among women. Hypertension is more prevalent
among women and blacks than men and whites. Heart
disease is more prevalent among men than women,
whereas non-Hispanic blacks tend to experience stroke
more often than other subgroups. Diabetes affects men
and women about equally, but prevalence among older
Hispanics and non-Hispanic blacks is greater than older
non-Hispanic whites. Osteoporosis is four times more
likely among women and substantially increases the risk
of fracture.4,6
Prevalent Activity Limitations
Estimates from a number of national surveys indicate
that a substantial proportion of older adults are hampered in their ability to perform a major life activity or
are limited in mobility, and despite some studies that
suggested this trend was improving, it may actually be
worsening.14 Furthermore, these surveys indicate that
these limitations in function increase with age, and they
are generally worse for women (who may contract more
disabling conditions such as arthritis), nonwhites, and
obese individuals.6,14 As has been noted in the overall
health status of the general population, it is commonly
agreed that the risks of physical disability are higher for
nonwhites and individuals with lower socioeconomic
status.6
As we shift from exploring population characteristics
associated with biological phenomena such as mortality
Percentage of people age 65 and over
who reported having selected chronic
conditions, by sex, 2005-2006
100
Men
Women
90
80
70
60
Percent
22
52
54
54
50
43
40
30
37
26
24
19
20
10
0
10 8
10 12
19
17
11 10
Heart Hyper- Stroke Asthma Chronic Cancer Diabetes Arthritis
disease tension
bronchitis
or
Emphysema
Note: Data are based on a 2-year average from 2005-2006.
Reference population: These data refer to the civilian noninstitutionalized
population.
Source: Centers for Disease Control and Prevention, National Center for
Health Statistics, National Health Interview Survey.
FIGURE 2-6 Chronic conditions among adults age 65 years and
older by sex. (From Federal Interagency Forum on Aging-Related
Statistics: Older Americans 2008: key indicators of well-being.
Washington, DC: U.S. Government Printing Office, March 2008.)
to consider the functional status of various groups,
which is a biopsychosocial phenomenon, a word of caution is always in order when interpreting subgroup statistics. First, the definitions for complex concepts such as
race/ethnicity or socioeconomic status may shift over
time from survey to survey, or have been imperfectly applied during data collection so that some subgroups are
over- or underrepresented in statistical analyses. The
concepts themselves may be proxy measures of other
factors that affect health status and function, such as
educational advantage, lifetime employment opportunity, or living environment, but are very difficult to measure directly and rarely studied.15 Statistically, these
findings may be highly correlated, which, for example,
leaves demographers uncertain as to whether race/
ethnicity or poverty or educational attainment better
explains poor health status from a statistical point
of view (i.e., greater explanatory power of a particular
variable in a more robust statistical model). Furthermore, even highly correlated relationships among variables may not be linear or parallel and may disproportionately affect individuals at different points on the
intersecting continua of education, income, or health
status. Alternatively, the models that are used to explain
functional deficits or activity limitations may not be
CHAPTER 2 Implications of an Aging Population for Rehabilitation
23
robust and multidimensional so that the statistical analyses incorporate data gathered from multiple domains
such as socioeconomic status and physiological impairment.16 Therefore, at the level of the individual person,
which is the level at which we measure activity limitation, functional deficit, or disability, inferences from
these models about the interplay between broad sociodemographic factors and health status or quality of life are
more tentative and, more than occasionally, not particularly useful to clinical decision making as they represent
factors outside the clinician’s control.
Increasing age is associated with increasing prevalence of
activity limitations, with the exception of mental illness.
Importantly for physical therapists, exercise and physical activity are not only critical interventions once health
conditions develop17-19 but they provide broad health
promotion opportunities. Physical therapists can assume
a key role in public health by instruction in exercise and
physical activity to achieve primary prevention and risk
reduction for development of several health conditions
(heart and circulatory disorders, fractures associated
with falls, and diabetes).20-22
Disease and Disability
Comorbidity and Disability
The six most common chronic health conditions that
result in activity limitations are arthritis and other musculoskeletal conditions, heart and other circulatory
problems, vision or hearing impairments, fractures and
joint injuries, diabetes, and mental illness (Figure 2-7).6
It is not unusual for physical therapists to find that the
patients with the most disability are also likely to have a
number of medical or health conditions that complicate
not only understanding of the genesis of functional deficit but treatment as well. For example, the individual
Selected Chronic Health Conditions Causing Limitation of Activity Among adults by Age: 1998 to 2000
(Number of people with limitation of activity caused by selected chronic health conditions per 1,000 population)
18 to 44
22.0
Arthritis/other
musculoskeletal
Heart/other
circulatory
Vision/hearing
6.8
2.6
Diabetes
Mental illness
65 to 74
73.2
5.4
4.2
Fractures/
joint injury
45 to 64
45.5
13.8
15.9
31.2
25.4
18.5
75 and older
117.8
110.8
193.1
170.9
82.5
48.6
38.4
42.5
10.4
18.6
11.4
10.7
Note: The reference population for these data is the civillian noninstitutionalized population.
Source: National Center for Health Statistics, 2002a, Figure 17. For full citation, see references at end of chapter.
FIGURE 2-7 Chronic health conditions causing activity limitations by age group. (From He W, Sengupta M, Velkoff VA, Debarros, KA: U.S.
Census Bureau population reports, P23–209, 651 in the United States: 2005. Washington, DC: U.S. Government Printing Office, 2005.)
24
CHAPTER 2 Implications of an Aging Population for Rehabilitation
with a stroke, who also has degenerative changes in the
foot and low tolerance for stressful activity secondary to
angina with exertion, can present a particular challenge
to the geriatric physical therapist’s knowledge and skill.
Although there is an emerging body of knowledge on
the effects of disease on function, less is known about the
effects of coexistent disease on function. Older adults
vary a great deal in the degree to which their chronic
comorbidity affects their functional capacities. However,
one comorbidity that has a documented negative effect
on function is obesity.23-26 Physical therapists working
with other health professionals can have a major impact
on functional decline by applying their evidence base in
exercise and physical activity to this threat to public
health.
FUNCTION
Physical Function and Disability
Physical, psychological, and social function are all dimensions of function that are included in the measurement of a person’s overall health status. Physical therapists address issues of physical function. In general,
independent physical function declines with age, and this
decline is influenced by a host of biological, psychological, and social factors. Function is not a static phenomenon and individual transitions in functional status are
more the norm than the exception. Function is also a
sociological phenomenon. Functional assessment does
not only measure the individual’s abilities to perform
tasks that are personally meaningful to the individual,
but it also measures performance essential to meeting
social expectations of what is “normal” functioning for
an adult. It is therefore necessary that the overall approach to functional assessment of an older adult include items that take into account what is “normal” in
that person’s social and cultural sphere. Physical functional activities can be subdivided into five areas: mobility, which includes transfers and ambulation; basic selfcare and personal hygiene (ADLs); more complex
activities essential to an adult’s living in the community,
known as instrumental ADLs (IADLs); work; and recreation.
Mobility. A primary concern of physical therapists in
performing a physical functional assessment of any adult
individual is to identify any functional limitations in mobility that can range from the ability to move independently in bed, transfer from bed to chair, ambulation on
level surfaces within the home, stair climbing, negotiating
uneven terrain, and walking for longer distances in the
community. Mobility is a component of ADLs, work,
and recreational activities.
Activities of Daily Living
Basic Activities of Daily Living. Basic ADLs include
all of the fundamental tasks and activities necessary for
survival, hygiene, and self-care within the home. A typical
ADL battery, which may be administered by a physical
therapist alone or cooperatively with other health professionals, covers eating, bathing, grooming, dressing, bed
mobility, and transfers. Incontinence and the ability to use
a bathroom are especially important elements in the assessment of physical function in some older individuals.
The ability of an adult in three aspects of independent
toileting function may require exploration of specific task
accomplishment: to get to the bathroom in an appropriate
time period, to move safely on and off the receptacle, and
to perform self-hygiene tasks.
Instrumental Activities of Daily Living. An examination and evaluation of IADLs addresses multiple areas
that are essential to living independently as an adult:
cooking, shopping, washing, housekeeping, and ability
to use public transportation or drive a car. For some individuals, it may also be appropriate to investigate the
ability to perform home chores such as shoveling snow
or yardwork.
Relationship between ADLs and IADLs. ​Most older
adults living in the community are generally independent
in both ADLs and IADLs (Figure 2-8). The relationship
between ADL and IADL is generally hierarchical; that is,
limitations in ADL usually predict limitations in IADL.
Thus, a home-care physical therapist working with a
patient recently returning home from an acute care hospital after a hip fracture would first explore the individual’s ability to do the tasks and activities encompassed
by basic ADL, such as transfers, ambulation, and toileting. If deficits were found, independence in these activities would serve as the first goals of intervention. If the
patient was independent in basic ADL upon initial examination, or became independent through the physical
therapist’s intervention, the therapist would then examine the older person’s limitations in performing IADL,
which supports a person’s ability to live independently in
the community. As part of the plan of care, as the patient
progresses to greater levels of independence, the physical
therapist will play an important role in identifying the
patient’s needs for formal caregivers, such as homemakers and home health aides, and in teaching families how
to manage a person’s limitations well enough so that the
individual may continue to reside in the community.
Work. One measure of adult competence is employment. Previously, it has been assumed that older adults
did not need to or want to work, based on data trends
that appear to have ended in the 1980s.4 Changes in
federal regulations have raised the minimum age at
which individuals may receive full Social Security benefits and mandatory retirement at a specific age for most
occupations is not typically permitted. Therefore, older
adults who want to, or need to, remain in the workforce
may do so if they are physically able to perform the tasks
of their employment. A substantial proportion of civilian
noninstitutionalized individuals older than age 65 years
are still counted in the workforce.4 Specifically, 34.4% of
the men and 24.2% of the women age 65 to 69 years
CHAPTER 2 Implications of an Aging Population for Rehabilitation
100
90
80
70
Percent
60
50
40
30
49
43
44
42
13
13
12
IADLs only
17
17
18
1 to 2 ADLs
6
4
6
5
3
5
5
3
5
5
3
4
3 to 4 ADLs
5 to 6 ADLs
Facility
1992
1997
14
20
20
10
0
2001
2005
Note: The Medicare Current Beneficiary Survey has replaced the National
Long Term Care Survey as the data source for this indicator. Consequently,
the measurement of functional limitations (previously called disability) has
changed from previous editions of Older Americans. ADL limitations refer to
difficulty performing (or inability to perform for a health reason) one or more
of the following tasks: bathing, dressing, eating, getting in/out of chairs, walking,
or using the toilet. IADL limitations refer to difficulty performing (or inability to
perform for a health reason) one or more of the following tasks: using the telephone,
light housework, heavy housework, meal preparation, shopping, or managing money.
Rates are age adjusted using the 2000 standard population. Data for 1992 and 2001
do not sum to the totals because of rounding. Reference: These data refer to Medicare
enrollees. Source: Centers for Medicare and Medicaid Services, Medicare Current
Beneficiary Survey.
FIGURE 2-8 Percentage of Medicare enrollees with limitations in
activities of daily living (ADLs) or instrumental ADLs (IADLs) or residing in a facility. (From Federal Interagency Forum on Aging-Related
Statistics: Older Americans 2008: key indicators of well-being.
Washington, DC: U.S. Government Printing Office, March 2008.)
were labor force participants in 2006. There is a striking
reduction among women age 70 years or older (7.1%) in
comparison to their male peers (24.2%). Overall, the
rates of labor force participation for older Americans
have grown for both men and women, with a much
steeper increase for women most likely due to generational changes in roles and societal expectations for
women working outside the home, particularly during
the past four decades.4
Physical limitations impacting one’s ability to work
can be examined by comparing an individual’s work
participation against the general conditions of work itself:
Is the individual working the anticipated number of hours
each week? Have the requirements of the job been modified in any respect to allow the individual to work? Does
the quantity or quality of work completed meet the anticipated standard of performance? Another approach to assessing work performance, first described by Nagi,27 is to
examine an individual’s ability to perform 10 particular
physical tasks associated with work disability: (1) walking
up 10 steps without resting; (2) walking a quarter of
a mile; (3) sitting for 2 hours; (4) standing for 2 hours;
(5) stooping, crouching, or kneeling; (6) reaching up overhead; (7) reaching out to shake hands; (8) grasping with
fingers; (9) lifting or carrying 10 pounds; and (10) lifting
25
or carrying 25 pounds. Using these data on “advanced”
mobility, one can infer what an individual’s capacity to
work would be. Interestingly, recent studies of the ability
to perform these kinds of physical functional tasks indicated increasing disability with every decade and a significant difference between men and women that persisted in
every age group (Figure 2-9).4
Recreation. Recreational activities are no less important than work to maintain a sense of well-being.
Clearly, more older men and women today are maintaining interests in recreational sports that they developed
earlier in life. Others are discovering the pleasures of
recreational sports as older adults. Functional assessment of recreational activities, however, is not limited to
sports. Many adults enjoy dancing and gardening, which
require a relatively high degree of balance, flexibility,
and strength. Even sedentary activities, such as stamp
collecting or playing chess, require a certain degree of
physical ability in the hand and upper extremity and
therefore may be functional measures of the outcomes of
intervention for some patients.
Heath and Health Care
Utilization of Services. Functional deficits are important markers for increased utilization of services,
especially with the use of formal services such as home
health care. Older patients in home health care tend to
be women, white, widowed, between the ages of 75 and
84 years, and living in a private residence. Almost half of
these receive care from family members.4
In contrast, nursing home residents are likely to be
women, especially those older than age 85 years.6 Nursing home utilization is generally on the decline, probably
attributable to emerging alternative care options such as
assisted living. Currently, it appears that any racial disparities in nursing home usage that may have previously
existed are disappearing especially among nursing home
residents aged 85 years and older.6 The vast majority of
nursing home residents need assistance with three or
more basic ADLs, particularly bathing and dressing.6 A
distinct racial disparity in functional status has been
documented among black nursing home residents, who
are more likely to be functionally limited in basic ADLs
than their nonblack peers.28
The majority portion of health care expenditures is
paid by public programs such as Medicare or Medicaid.6
Yet nearly 20% is paid out of pocket and a smaller
proportion out of private insurance. Older adults in
poverty or near poverty have the worst health status
(Figure 2-10) and also incur the greatest health care
costs.6,29
Current Trends and Future Possibilities. Changes
in the demographic characteristics of the U.S. population
represent a critical challenge to geriatric physical therapists. Older adults are expected to live longer than ever
before, but the quality of their lives in these added years
CHAPTER 2 Implications of an Aging Population for Rehabilitation
26
Percentage of Medicare enrollees age 65 and older who are unable
to perform certain physical functions, by sex, 1991 and 2005
1991
Men
90
90
80
80
70
70
60
60
50
40
50
40
32 32
30
30
20
10
0
Women
100
Percent
Percent
100
2005
8
14 15
10
3 3
2 1
Stoop/ Reach Write
kneel over
head
19 19
9 8
Walk
Lift Any of
2-3 10 lbs. these
blocks
five
20
10
0
15
23 23
18
6 5
18
16
3 2
Stoop/ Reach Write
kneel over
head
Walk
Lift
Any of
2-3 10 lbs. these
blocks
five
Note: Rates for 1991 are age adjusted to the 2005 population.
Reference population: These data refer to Medicare enrollees.
Source: Centers for Medicare and Medicaid Services, Medicare Current Beneficiary Survey.
FIGURE 2-9 Percentage of Medicare enrollees who cannot perform selected physical tasks by sex. (From Federal
Interagency Forum on Aging-Related Statistics: Older Americans 2008: key indicators of well-being. Washington, DC:
U.S. Government Printing Office, March 2008.)
Poverty status1
Poor
Near poor
Not poor
95% confidence interval
60
50
Percent
40
30
20
REFERENCES
10
0
1
is still a matter of conjecture. Aging with multiple diseases further aggravates a propensity toward physical
decline with advanced age. Function deficits are the expected outcomes of disease; in turn, functional limitations predict increased utilization of services, further
morbidity, and death. Future research must establish the
ability of physical therapy to delay the onset of disease
and disability and to prolong optimal function well into
old age.
55-64
65-74
75-84
85 and
older
Defined as follows; poor (family incomes below poverty threshold);
near poor (family incomes 100% to less than 200% of poverty threshold);
and not poor ( family incomes 200% of poverty threshold or greater).
Note: Data are based on household interviews of a sample of the civilian
noninstitutionalized population.
Data source: CDC/NCHS, National Health Interview Survey, 2004-2007.
FIGURE 2-10 Percentage of adults age 55 years and older in fair
or poor health by age group and poverty status. (From Schoenborn
CA, Heyman KM: Health characteristics of adults aged 55 years and
over: United States, 2004–2007. National health statistic reports,
no. 16. Hyattsville, MD: National Center for Health Statistics, 2009.)
To enhance this text and add value for the reader, all
references are included on the companion Evolve site
that accompanies this text book. The reader can view the
reference source and access it online whenever possible.
There are a total of 29 cited references and other general
references for this chapter.
CHAPTER 2 Implications of an Aging Population for Rehabilitation
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