Growing aging population
Over the last century life expectancy has increased, mostly due to improvement in mortality among infants and children. In 1900, life expectancy at birth in the United States was 52 years for men and 58 for women; by 2015 it was 81 for men and 86 for females, a rise of about three decades over the span of a century. Globally in 2015 life expectancies were 69 and 74 years for men and women (WHO n.d.). For people who have reached older ages, life expectancy has also improved but by fewer years: in 1900 65-year-olds in the United States could expect to live 11 more years for males and 12 for females; by 2015 these were projected to be 17 years for men and 20 for women (Bell and Miller n.d.).
With this increase in life expectancy has come a substantial increase in the share of the population that is older. In the US, the share of the population aged 65 and over rose from 4.1% in 1900 (around 3 million) to 12.4% in 2000 (nearly 35 million), and is projected to reach 20% in 2030 (almost 73 million) (West et al. 2014). Some other countries that have less immigration bringing younger people to the country will have populations with still higher shares of older adults.
Smaller households
With population shifts as well as a decrease in some countries in traditional multigenerational households (in which a parent might live in the home of a child, for example), the number of older households will also grow. In the U.S., 57% of households headed by those 65 and over are expected to be single-person units by 2035 (JCHS 2016, p. 6). Already, just under half the women in the U.S. aged 85–94 live alone (Fig. 1). This pattern appears worldwide (Prioux et al. 2010, p. 385). Of course married households are also small and have challenges, but this will be exacerbated by the increase of solo households.
There are many reasons for this rise in single-person households. Lower marriage rates and higher divorce rates mean fewer people enter older age as married couples (JCHS 2016, p. 6; Wang and Parker 2014). Women’s longer life spans, combined with a tendency to marry older men, mean that on average even those women who do marry and remain so will be widows in their final years.
Solo living may increase further as fewer older adults reside with their children in the future. In most parts of the world, families are having fewer children, meaning in the future there will be fewer options for living with, or receiving care from, children later in life. There are many reasons for lower birth rates and childlessness but generally higher education, later marriage, divorce, workforce participation, and the like have contributed. In the OECD, rates of childlessness increased from the mid-1990s to 2010, with only four countries showing a decrease. By 2010, Austria, Canada, Finland, Ireland, Spain, the UK, and the United States had childless rates at or over 19% of those aged 40-44 (OECD 2015). Even having children is not a guarantee of their helping in old age. Daughters who have traditionally provided care are often in the paid workforce, and not all live close to a parent (Kasper et al. 2015). This in an international phenomenon—in 1960, 87% of Japanese people over 65 lived with their children, but by 2005 it was 47% (NIA and WHO 2011, p. 23). The full force of this trend has not yet been felt.
Single-person households, particularly those that are female, generally have fewer economic assets. In 2016, in the U.S., according to the American Community Survey, female householders aged 65 and over living alone had a poverty rate of 18.7% compared with 14.5% for men living alone and 4.1% for married couple families. Rates for Black and Hispanic/Latino women aged 65 and over living alone were even higher at 29.2 and 41.2%. In the U.S., compared with married counterparts, such households also have higher rates of disabilities, and more often need to pay for care (JCHS 2016, p. 6).
Trends toward home care
With lower incomes and greater likelihood of needing paid care, small households will be particularly vulnerable to isolation and unmet physical and social needs. Yet at the same time, policy changes and consumer choices have reduced the percent of older adults residing in nursing homes in many countries. In the U.S., the share of older adults in nursing home residents fell steadily from 1990 to 2015, even as the older population has increased. In 2016, according to the American Community Survey, about 1.24 million people over age 65 (2.6% of the population over 65) were in such facilities, down from about 5% in 1990. Residents are more likely to be very old; in 2010, about 10.4% of Medicare enrollees aged 85–94 and 24.7% of those 95 and over lived in nursing homes (West et al. 2014, pp. 136–137). However, overall more people are living outside institutions meaning that the balance of support—physical and social—will need to be delivered to their home, neighborhood, and community environments.
Variations and vulnerabilities in the olds
While older people are diverse, age does bring an increased likelihood of experiencing disability. For the U.S. population over 85, 53% have difficulty walking and climbing stairs; 50% doing errands alone; 31% dressing and bathing; 35% hearing; 29% remembering, concentrating, and making decisions; and 18% seeing (West et al. 2014, p. 43). Again, this is an international phenomenon (Lafortune et al. 2007).
Such older people often need help with what are known as activities of daily living (ADLs), typically “eating, dressing, getting into or out of a bed or chair, taking a bath or shower, and using the toilet,” and instrumental activities of daily living (IADL) including things like meal preparation, money management, shopping, housework, and telephone use (U.S. National Cancer Institute n.d.). Outside the home, they may have difficulty accessing services because they do not drive and/or live in places lacking services, such as outer suburbs and rural locations.
Having multiple challenges with everyday functioning is often associated with a condition dubbed frailty which affects a very large number of older people. Frailty is not a single, clearly defined condition but rather represents the cumulative interactions of multiple factors. At a minimum, medical definitions focus on having at least three of five characteristics: decline in weight loss (shrinkage), exhaustion, slow gait speed, small amounts of activity, and general weakness measured via grip strength (Fried 2016, p. 3). Other features may also be included in broader, more sociological definitions such as cognitive impairment, urinary incontinence, balance problems and falls, difficulty with activities of daily living, diminished ability to give and receive social support, and fluctuations in disability (Clegg et al. 2013; Barrett and Twitchin 2006; Harttgen et al. 2013). Causes are complex and much debated but may be related to advanced physical aging and reactions to a lifetime of stressors (Buckinx et al. 2015).
A study of almost 80,000 people aged 50 and over from Europe and major low- and middle-income countries—China, Mexico, Ghana, South Africa, India, and the Russian Federation—found high frailty prevalence for those aged 85–89 (21–45%) and 90 and over (23–47%) (Harttgen et al. 2013). Other studies of high- and middle-income countries, including the U.S., have found similar numbers (Fried 2016; Clegg et al. 2013). A study of 7439 adults in the U.S. found a substantial group with 1–2 of the five features that commonly define frailty (shrinkage, exhaustion, slow gait, low activity, and weakness). This group includes 45.5% of those 65 and over, 47.5% of those 85–89, and 48.7% of those 90 + living in the community (Bandeen-Roche et al. 2015, p. 1429). These are large numbers that deserve to be on the radar screen of urban design.
Socioeconomics also make a difference. Those with low incomes and educational attainment tend to experience frailty earlier, leading to higher rates at any particular age group (Harttgen et al. 2013; Bandeen-Roche et al. 2015, p. 1429). Yet those with high incomes and education live longer and experience frailty, just more likely at older ages. Even if better population health means that people experience fewer symptoms of frailty at younger ages, growing longevity means there will be large numbers of people in their 80s and beyond facing this challenge. In addition, the Bandeen-Roche et al. (2015) study found variation across race/ethnicity. While non-Hispanic whites aged 65 or over had a frailty rate of 13.8%, African-Americans and Hispanics of the same age range had frailty rates of 22.9 and 24.6%, respectively. The pre-frail numbers for all groups were similar, however, ranging from 45.3 to 46.5% of those 65 and over.
While disability rates among those who are very old have been declining a little in countries like the U.S., countering that is the larger numbers of the very old (He et al. 2016; Chernew et al. 2016). More importantly, the problems of old age are not static, but emerging over time, incrementally or more suddenly, through a crisis. A person’s environment may need to accommodate new needs and limitations. Whatever the situation, most people reaching advanced age will experience some limitations, and that is particularly the case for those with other disadvantages. If people want to age in place, home and community environments need to be able to support such circumstances, or there need to be nearby alternatives for aging in community.
Environmental fit, needs, and urban design
Much of the work on environments for older people dealing with impairments has focused on the house. For example, work by the Joint Center for Housing Studies using data from the 2011 American Housing Survey found that “less than 4% of single family homes, the most common form of housing for older adults, offers three of the most critical accessibility features… (single-floor living [with bedroom and bathroom on the main floor], extra-wide hallways and doors, and zero-step entrances)” (JCHS 2016, p. 9). Issues with home design, adaptation, maintenance, and location have been identified internationally (Barrett and Twitchin 2006, p. 148; Byles et al. 2014).
The scale of urban design is typically seen as being larger than the home—the block, district, or beyond. A number of the solutions we outline in this paper do deal with housing but at this larger scale, providing innovative ways of clustering housing to help provide services or social supports, or dealing with aging in place at a neighborhood or district level.
The home is also connected to a wider network of services, accessed by older people venturing out or through service people coming to the home, particularly for those services related to housework or personal care such as bathing, dressing, or eating. Both types of service delivery can be challenging due to home location. Of those over 65 in the U.S., roughly half live in rural areas or in metropolitan areas with less than 1 housing unit per acre, 28% in areas from about 17–3.2 units per acre (broadly suburban), and only 23% in areas more than 3.2 units per gross acre at the census tract level (JCHS 2016, p. 30). Low density and lack of transportation options can make it more difficult to engage with one’s community—yet even in more dense urban environments problems can occur. For example, vibrant districts may be congested, with noise, traffic, uneven lighting, and potential for being bumped, discouraging older adults from venturing into public (Hunter et al. 2011; Clark and Nieuwenhuijsen 2009).
Challenging locations provide a rationale for some of the purpose-built housing models that provide services and housing together in one location. Research findings also show that older people living with higher proportions of those of similar age have fewer symptoms of depression and better self-rated health (Clark and Nieuwenhuijsen 2009), as well as higher rates of formal volunteering (Park et al. 2017). Yet such models are not for everyone, making the case for other alternatives.
Overall there are few perfect answers. Core cities have many services but also risks such as traffic and potential for falls. Suburban town centers and small towns might offer services and supports as well as easier mobility, but many suburban residents are not in such centers and risk isolation, as do those in very low density and rural areas (Forsyth 2014). Of course, the situation is quite different in a place like China where densities are very high, but anecdotal evidence points to isolation among older people in new high-density environments where they may have moved to live with working children but spend much of the day without them and far from their old friends. Very supportive physical environments might allow frail older people to function better for longer, but these require a coordinated set of solutions going beyond physical design, as we describe below.