The following is a guest post by Jennifer Gilbert, a research assistant for Dr. Ashish Jha at the Harvard School of Public Health and for The Incidental Economist. She graduated from Boston University in 2014. You can follow her on Twitter: @jenmgilbert.
When people with visible disabilities pass by, they regularly attract the attention of others. Some well-meaning observers may imagine themselves in the same position and envision a world of sadness. But this is not the world that most people with chronic illness or disability inhabit.
Research shows that most people at least partially adapt to their condition. However, study design matters. The more optimistic studies assumed that having a high level of self-reported well-being equates to a return to baseline happiness, while less optimistic results emerged from research considering data before accidents, enabling analysis of life satisfaction over time.
One early, optimistic theory of adaptation stems from a 1978 study, “Lottery Winners and Accident Victims: Is Happiness Relative?” The investigators interviewed 29 paralyzed accident victims and 22 lottery winners, and found after one month to one year of time had elapsed, both groups returned to the level of happiness they’d had before winning the lottery or becoming injured. The authors coined the term “hedonic adaptation” for the idea that people have a general baseline level of happiness and will return in time to this set point as they navigate the ups and downs of life.
A large body of research has examined positive adaption to disability. These studies found that after developing a disability, self-reported happiness increases over time. However, the majority of them only measure level of happiness after onset of disability; they don’t use a baseline level of happiness for comparison.
According to one study of individuals in 11 social networks of persons with disabilities, a majority of the respondents with moderate to serious physical disabilities reported having an excellent or good quality of life. Another study found that 100 disabled participants reported levels of well-being that were only slightly lower than those of age-matched nondisabled people on scales of psychological well-being, life satisfaction, and depression. More recently, a 2005 study found that hemodialysis patients were no less satisfied with their lives than nondisabled people, and several studies have found paraplegics adapt in many ways, such as reporting improved mood within weeks of their accidents and experiencing similar happiness to others. These studies correlate higher levels of happiness with greater independence, supportive social networks, and specific personality traits.
It’s important to note that even the most heavily cited studies above had a sample size of less than 150 people. Furthermore, these studies interviewed participants directly about their adjustment to their disabilities, so they may have recruited a sample that was more outgoing or more invested in the research.
Another major issue with the above studies is that none of them had access to baseline (pre-disability) happiness. Other, more recent studies do, however. They found only a partial return to baseline happiness after disability. Richard Lucas examined the happiness and life satisfaction of people who became disabled, based on nationally representative studies of over 39,000 households in Germany and 27,000 households in Britain. From both data sources, Lucas found substantially lower levels of life satisfaction and higher levels of distress in people after they became disabled. He followed the German population for an average of 7.18 years before the onset of their disability and 7.39 years after, and the British population for an average of 3.48 years before the onset and 5.31 years after. People had a significant decline in happiness for the first year of their disability, and partially adapted, but did not return to their pre-disability baselines level of happiness. More severe disabilities were correlated with a lower final happiness level. These results held true even when controlling for employment and income changes.
Andrew Oswald and Nattavudh Powdthavee used the same British dataset as Lucas and found that those who became moderately disabled (able to still do most day-to-day activities, such as cooking, dressing oneself, and walking for ten minutes of less) return to about 50% of their previous level of happiness, and those who are severely disabled return to about 30%.
These studies have some notable strengths. They are based on large surveys of individuals not selected because of disability, and their level of happiness was followed before, during, and many years after developing their conditions. This allows for a more rigorous analysis of adaptation than matched control or retrospective studies.
It’s worth noting that the population in these studies that developed disabilities also had significant decreases in happiness as much as two years before their disability developed. This may reflect the unfortunate reality that people living in more difficult circumstances are disproportionately likely to develop a disability. So, it’s possible that some of the lower happiness measured after disability (relative to baseline) was not due directly to the disability itself, but to unobservable, progressive factors correlated with it.
Furthermore, disability is a broad term, and it is probable that those who have a disability due to a terminal illness experience greater decreases in happiness than those who develop a disability independent of another condition. The two studies above don’t differentiate between type or cause of disability.
Regardless, there is evidence that people psychologically adapt to their disabilities, but only partially. This isn’t to say that they are depressed – many still report extremely high levels of happiness (higher than many people who aren’t disabled, in some cases), just not necessarily as high as before developing their disability. Furthermore, it doesn’t mean people with disabilities lead less fulfilling lives. Like losing a loved one, developing a disability has an indelible effect on one’s day-to-day life. People with disabilities may not automatically return to their baseline happiness, but they can lead lives as fulfilling as those without disabilities, especially if they are given the support they need.