Obesity in old age may not kill, but may disable

By Amy Norton

NEW YORK (Reuters Health) – Obesity after the age of 70 may
not shorten a person’s life, but it may lead to more years of
disability, a new study suggests.

Researchers found that among more than 7,100 U.S. adults
age 70 and older, those who were obese had a life expectancy
comparable to their leaner peers’. However, obese men and women
spent more of their later years with some physical disability.

It’s unclear why obesity does not seem to affect older
adults’ life expectancy despite its link to greater physical
limitations, according to the study’s lead author, Dr. Sandra
L. Reynolds of the University of South Florida in Tampa.

The findings, she told Reuters Health, may reflect a
“survivor effect.” That is, obesity and its related ills may
increase the risk of death at younger ages, while obese adults
who reach the age of 70 and beyond may be no more likely to die
than their thinner peers.

Also uncertain are the reasons for the greater disability
found among obese elderly, according to Reynolds. She said she
suspects one factor may be chronic inflammation in the body, a
state thought to contribute to illnesses such as heart disease.
Obesity is also a risk factor for arthritis of the knee and
hip, potentially disabling conditions.

Obese adults in the study did have high rates of high blood
pressure, diabetes and arthritis, Reynolds and her colleagues
note in a report published in the journal The Gerontologist.

The researchers based their findings on data from a study
that followed 7,132 men and women age 70 and older for about 5
years. Overall, obese adults were somewhat less likely to die
during the study period, but were more likely to develop a
limitation that kept them from performing daily tasks.

For example, a 70-year-old woman could expect to live
another 15 years, regardless of her weight. But, on average, an
obese woman spent more than 7 of those years disabled, while
leaner women suffered from a disability for less than 5 years.
Similar differences were seen among men.

Few studies, Reynolds and her colleagues write, have looked
at ways to reduce obesity among older adults. But finding
effective ways to do so, they conclude, “could have a major
impact on disability rates in older adults.”

SOURCE: The Gerontologist, August 2005.