Obese American seniors seem to be suffering more from physical disabilities, while their cardiovascular health has improved somewhat, according to an article in the The Journal of the American Medical Association (JAMA), November 7th issue.
The authors explain that recent studies have indicated that America’s obese population may have gotten healthier since the 1960s. It seems that the prevalence of high cholesterol and hypertension (high blood pressure) among America’s obese people has fallen over the last 40 years. What is not clear, however, is whether this group is enjoying better health outcomes in other areas.
Dawn Alley, Ph.D., and Virginia W. Chang, M.D., Ph.D., of the University of Pennsylvania, Philadelphia, carried out a study to find out whether the link between obesity and disability has changed among the country’s seniors (over 60s). A previous analysis had indicated that obesity’s impact on disability over time is constant – in fact, disability increases over time in both obese seniors and non-obese seniors.
The authors wrote “Disability in this age group is of particular importance, given the current context of population aging and an increasing prevalence of obesity among older-aged individuals. Furthermore, obesity-associated disability is associated with significant burden in terms of both quality of life and health care costs in this age group.”
They examined data from the National Health and Nutrition Examination Surveys (NHANES III 1988-1994 and NHANES 1999-2004). The study involved 9,928 adults over sixty years of age – all of them had their BMIs (body mass index) measured. They were all assessed for their ease/difficulty in performing tasks in two disability domains׃
1 – Functional Limitation
– walking one quarter of a mile
– walking up 10 steps
– stooping
– lifting 10 pounds
– walking between bedrooms
– standing from an armless chair
2 – Activities of Daily Living Limitation (ADL)
– getting in and out of bed
– eating
– dressing
During 1988-1994 (Time 1) 23.5% of those over 60 had a BMI of over 30 (obese)
During 1999-2004 (Time 2) 31.7% of those over 60 had a BMI of over 30 (obese)
During both these Times obese individuals were found to have a raised risk of having a functional impairment compared to those whose body weights were normal. The researchers found that the obese people in Time 2 were more likely to have an ADL impairment, compared to Time 1. By looking at trends over time the authors found that the prevalence of functional impairment did not change appreciably among normal-weight individuals, but increased among obese individuals by 5.4%, from 36.8% to 42.2%.
The chances of becoming functionally impaired were the same for non-obese individuals in both Time 1 and Time 2, but increased 43% among the obese people. There was a growing link between obesity and disability over time. During Time 2, an obese person was 78% more likely to have some kind of functional impairment compared to a person whose weight was normal, while during Time 2 the obese person’s risk was 2.75 times higher.
As far as ADL limitations were concerned, the chances of experiencing ADL impairment among obese individuals was not substantially different from normal weight individuals during Time 1. Between 1988-1994 and 1999-2004, the chances of ADL impairment fell by 34% within the non-obese population, but did not change for the obese people. At Time 2, the chances of ADL impairment for obese individuals was about double compared to those with normal weight.
The researchers concluded “Obese participants in NHANES 1999-2004 were more likely to report functional impairments than obese participants in NHANES III (1988-1994), which suggests an increasing risk of disability in the obese population. Furthermore, reductions in ADL disability observed among non-obese older individuals did not occur among obese individuals. Taken together, these findings suggest that recent improvements in cardiovascular health have not been accompanied by a reduction in disability burden among obese individuals; instead, the risk of some types of disability is actually increasing.”
“The Changing Relationship of Obesity and Disability, 1988-2004”
Dawn E. Alley, PhD; Virginia W. Chang, MD, PhD
JAMA. 2007;298(17):2020-2027.
Written by Christian Nordqvist