Casualties of the July 1995 heat wave in Chicago

From Chicago Bureau Chief Jeff Flock

CHICAGO (CNN) -- It was almost unbelievable. The numbers of dead were so staggering from the July 1995 heat wave -- 733 by the end -- that some openly wondered whether the numbers weren't being exaggerated.

Three years after the mass burial of heat victims, new information finds instead the crisis may have been under-reported.

"Many of our patients died in the hospital several weeks later," said Dr. Jane Dematte of Michael Reese Hospital. "They would not have all been counted in the medical examiner's office."

A study in the August issue of the Annals of Internal Medicine went back to a dozen Chicago hospitals that treated the heat patients and looked more closely at the people who didn't become victims right away.

"Close to 50 percent who required admission to the hospital eventually died," Dematte said.

The study found of the patients, 21 percent died in the hospital, 28 percent within a year. An additional third remained disabled when they left the hospital. None were better a year later.

Perhaps most troubling: The study raised questions about whether some of the deaths and disabilities could have been prevented.

"When people come into the hospital with heat stroke, it's like we are already behind," said Dr. Maurice Ndukwu, assistant professor of medicine at the University of Chicago Medical Center and senior author of the study.

Of the 58 heatstroke patients in the study, only one was properly cooled within the recommended time.

Some were treated for classic stroke, given CT scans or other treatment when priority one was simply bringing their body temperature down by immersing them in cool water.

The heat wave that hit three years ago was neither the longest nor hottest in U.S. history, but it turned out to be one of the deadliest.

Given the length and intensity of what Texas is now experiencing and the relatively few deaths reported so far, this study suggests the story there is far from over.

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