Can Heart Deaths Continue to Drop?

June 6, 2007 -- The 20-year drop in U.S. heart deaths is half due to new treatments, half due to better lifestyle -- but swelling obesity threatens these gains.

The finding comes from a CDC effort to explain why, for the last two decades, fewer and fewer Americans die of heart disease.

In a tour de force of statistical analysis, CDC researchers Earl S. Ford, MD, MPH, Janet B. Croft, PhD, and colleagues came up with an answer.

"We were glad to find that 44% of this decrease was due to fewer risk factors, and 47% was due to treatments," Croft tells WebMD. "Both the patient and medical communities should be excited by these results."

What did Americans do to lower their heart disease risk?

• Lowering our cholesterol levels accounted for 24% of the lower risk.
• Lowering our blood pressure accounted for 20%.
• Fewer smokers accounted for 12%.
• More physical activity accounted for 5%.

Is the CDC satisfied? No way.

"It could have been better, Croft says.

That's because increases in body mass index -- in other words, obesity -- offset the gains by 8%. And diabetes -- also linked to obesity -- offset the gains by another 10%.

"I have concern that if we do not make a turn in this obesity epidemic, we could go back to the bad old days and see coronary heart disease increasing again," Croft says.

The CDC study appears in the June 7 issue of The New England Journal of Medicine.

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