Homelessness and inadequate home heating are factors in the jump in the number of freezing deaths in the United States, which has more than doubled in a decade, federal officials say.

The National Center for Disease Control reported Thursday that in 1985, the latest year for which complete statistics are available, 1,010 people died from exposure to the cold, a 137 percent increase from the 427 deaths reported in 1976.More research needs to be done, but the numbers strongly suggest more and more Americans are dying from the cold, the CDC said.

The vast majority of the deaths were technically due to hypothermia - decreased body temperature, or freezing to death.

"It's either increased cold . . . which is unlikely, or it's more people exposed to more intense or more frequent stresses from the cold," said Dr. Edwin Kilbourne, CDC researcher.

Kilbourne said that while it's possible that many of the deaths were due to inadequate home heating, another part of the problem is the significant number of people who have no shelter at all to call their own.

"A person who has to sleep outdoors, they certainly run a higher risk of problems like hypothermia," he said.

Social service officials have said the number of homeless people has risen in recent years. Estimates of the number nationwide are as high as three million.

As the nation ages, Kilbourne said, more research is needed to determine just who is freezing to death: homeless people - typically middle-aged men - who have no shelter from the cold or older people less able to withstand low temperatures and possibly living with insufficient heat.

"In the past, at least in certain cases, hypothermia has been thought of as a problem of middle-aged male alcoholics . . . a `street person.' We really don't know if that remains the profile," Kilbourne said.

People 60 and older are particularly susceptible to hypothermia and account for more than half of all hypothermia deaths, according to previous studies. Children under a year old also are at high risk, although hypothermia deaths are rare in children.

"Hypothermia prevention programs should focus on persons particularly susceptible . . . and those likely to be subjected to unusual cold stress," the Atlanta-based CDC said in its weekly report.

The agency said special attention should be paid to proper nutrition and home heating for the elderly, shelter for the homeless and precautions for young people in the outdoors, such as skiers and hikers.