"Our study showed an excess mortality, meaning these are people that would not have died, had it not been for Katrina, " said Dr. Kevin Stephens, who is director of the New Orleans Health Department and the study author.

CNN: Doctor's free clinic a 'tiny Band-Aid' to pain of Katrina

Using all-cause mortality tells us nothing about how long people may have lived with debilitating chronic conditions associated with excess body weight.

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