Gaining Weight with Age Takes a Toll

Gaining weight with age is more typical than not and many people age 65 or over are not concerned with this additional weight. Previous scientific studies indicated that elevated Body Mass Index (BMI)) at retirement age and older did not affect a person’s lifespan, and some studies found elevated BMI may even extend it. The earlier studies, however, may have been flawed. In a new study, Ryan Masters and colleagues have found that the death risk for Americans with obesity increases with age.

This study in the American Journal of Epidemiology challenges previous studies that found that the association between obesity and mortality risk weakens with age. The researchers used statistical models in this research to examine how age affects the relationship between obesity and death risk. They made use of a series of Cox regression analysis models in data from 19 cross-sectional, nationally representative waves of the U.S. National Health Interview Survey (1986–2004). They then joined that data to the National Death Index through 2006 to analyze age patterns in the obesity-mortality association between ages 25 and 100 years. They found the obesity-mortality relationship is estimated to grow stronger with age.

What was wrong with earlier studies if the results from this new analysis are correct? The researchers noted that the previous studies using data from the National Health Interview Survey may have been biased because the survey did not include individuals who were in an institution such as a hospital, an assisted-living center, or nursing home, thus leaving out a large population of not-so-well-off seniors. The survey data likely included information on healthy seniors. It also may have been skewed because many people with obesity fail to live to age 65.

The study examined data from nearly 800,000 adults between 1986 and 2004 and found the risk for death from obesity climbed with age. The researchers compared the survival of respondents with a normal or overweight BMI to respondents with obesity. They found that respondents with higher BMI had a higher mortality risk, with extreme obesity having the greatest mortality risk. Individuals with a BMI over 40 resulted in men’s mortality risk at 65+ years increasing 2.6 to 3.6 times, and women’s mortality risk increasing by 2.6 to 2.8 times.

Click here to read more in the Huffington Post and here to read the abstract from the American Journal of Epidemiology.

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