Men and women who are obese in middle age will be up to twice as expensive to cover under Medicare, the government health plan that kicks in after Americans reach age 65, according to new study findings reported Tuesday.

The investigators found that men and women who were severely obese between the ages of 33 and 64 accumulated more than $170,000 in Medicare charges over their lifetimes.

Specifically, average annual Medicare charges for normal-weight women worked out to be $6224, compared with $12,342 for severely obese women; the corresponding charges for men were $7205 compared with $13,674, the authors report in this week’s Journal of the American Medical Association.

“There is a long, long list of diseases related to overweight and obesity,” lead author Dr. Martha L. Daviglus told Reuters Health. “The weight is making the individuals sicker.”

She explained that the main culprits are likely cardiovascular disease, diabetes and certain cancers, as well as the diseases that are aggravated by obesity.

Nevertheless, she said she was “very surprised to see these huge differences.”

The best way to control these costs is to get the message out to young children and teenagers about the dangers of obesity, to prevent the problem before it starts, Daviglus said.

And for people who are already overweight or obese, the key is to help them lose a lot of weight - and keep it off, she said.

“Certainly, it is going to be a different picture if they lose weight,” the researcher, based at Northwestern University in Chicago, said in an interview.

Around 130 million Americans are currently obese or overweight. By 2050, the proportion of people 65 and older is expected to increase to 20 percent.

To investigate how these trends will affect Medicare, Daviglus and her team reviewed weight data gathered from 9978 men and 7623 women between 1967 and 1973, then tracked their healthcare charges once they became eligible for Medicare.

All participants were between 33 and 64 years old when the study began. None had heart disease or diabetes at the outset of the study.

The researchers found that the more men and women weighed in middle age, the more they racked up in annual Medicare charges. The same trend existed in overall lifetime Medicare charges, as well as in charges related specifically to cardiovascular disease and diabetes.

SOURCE: Journal of the American Medical Association, December 8, 2004.