The next time you hear someone pat themselves on the back because their grandma is still living in her own place, consider this: Almost 6 percent of the Medicare population, or 2 million Americans, are homebound, meaning they rarely or never leave their house.

That’s more than the 1.4 million people estimated to be living in nursing homes.

The first national estimate of the older homebound population in the United States is part of a new study about the epidemiology of the homebound published in the JAMA Internal Medicine journal this week.

Epidemiology is the science of studying the factors that determine the frequency and distribution of disease, injury, and other health-related events and their causes. This study’s focus was elderly people with assorted ailments.

The lead author is Katherine Ornstein, Ph.D., M.P.H., assistant professor of geriatrics and palliative medicine at the Icahn School of Medicine at Mount Sinai in New York.

The numbers are no surprise to Ornstein, who said previous studies came up with similar estimates. But the numbers in this study “may be helpful for developing and evaluating the effectiveness of initiatives and programs to care for the homebound,” she said.

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Why People Become Shut-Ins

There are many reasons why a person becomes a shut-in.

In New York City, for example, an older person might live in a building where they have to walk up three flights of stairs. Then they fall or become too frail to handle those steps.

Or it may be a person in rural North Dakota, where stairs are not the problem. But the person no longer drives and there are no nearby services.

Or perhaps it’s a question of general mobility for a morbidly obese patient.

These are people who can’t get to the doctor’s office, can’t get to the grocery store, can’t get out to socialize. They become invisible — for a while.

“They are invisible until something happens,” Ornstein noted. And that “something” is likely to be bad, perhaps requiring an ambulance ride or hospital stay.

The numbers are daunting and they are only likely to get worse. The baby boomers are quickly moving toward old age. Some will become debilitated or chronically ill.

“In 50 years this population will double,” Ornstein said.

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Health Issues for the Homebound

While homebound individuals have more chronic illness and disability than their non-homebound counterparts, the study suggests that homebound status may also be due to social, psychological, and environmental phenomena.

There is a sizeable group of individuals who are not homebound because they have caregivers who help them get out. Caregivers might be family members, friends, or paid attendants.

“Social support may be as important as medical factors in determining whether a person is completely homebound,” Ornstein said.

The researchers included demographic data such as age, gender, race, education, marital status, income, language, and living arrangements in their study.

Respondents were given a mobility survey and then asked how frequently they left the house and if they needed assistance to do so.

The study defined homebound persons as those who never or rarely left the home in the past month. A second group was defined as semi-homebound. They left the home only with assistance, or had difficulty or needed help leaving the house.

Although the problem is widespread, there are programs in place to help and many projects in development. Ornstein recalled that doctors at hospital clinics began to wonder where some of their sickest and most vulnerable patients were and why they were skipping appointments.

“That’s how Mount Sinai’s visiting doctors program started,” she said.

Technology also provides part of a solution for sick and isolated older adults — what Ornstein called “the most medically complicated” population. For example, a visiting nurse can take pictures of a sore that won’t heal and send them to an offsite doctor for diagnosis. Sometimes that’s enough to prevent a visit to the doctor’s office.

According to the study, the homebound have high disease and symptom rates, substantial functional limitations, and higher mortality than the non-homebound. All good reasons for developing new ways to alleviate the problem.

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