Premature death rates in the United States have fallen for some groups but risen in others, a federal study says.

Researchers looked at death certificate data from 1999 to 2014. They found that rates of premature death (between ages 25 to 64) declined among blacks, Hispanics and Asian/Pacific Islanders. At the same time, the rates went up for whites and American Indians/Alaska Natives.

"Death at any age is devastating for those left behind, but premature death is especially so, in particular for children and parents," said study senior author Amy Berrington, from the U.S. National Cancer Institute.

"Our study can be used to target prevention and surveillance efforts to help those groups in greatest need," she said in an agency news release.

There were fewer deaths from cancer, heart disease and HIV for blacks, Hispanics and Asian/Pacific Islanders. Success in public health programs to reduce tobacco use is one reason for these drops. Another is medical advances to improve diagnosis and treatment, the researchers said.

Despite these improvements, overall premature death rates are still higher among blacks than whites.

Significant jumps in accidental deaths -- mainly drug overdoses -- were the primary reason for the increase in premature deaths among whites and American Indians/Alaska Natives. There were also increases in suicides and liver disease, the study reported.

Death rates rose as much as 5 percent a year for 25- to 30-year-old whites and American Indians/Alaska Natives during the study period. That's similar to increases seen at the height of the AIDS epidemic in the United States, researchers said.

One positive trend was seen in whites -- cancer and heart disease deaths went down, the study found.

The findings were published Jan. 25 in The Lancet.

Lead author Meredith Shiels is also with the National Cancer Institute. She said, "The results of our study suggest that in addition to continued efforts against cancer, heart disease and HIV, there is an urgent need for aggressive actions targeting emerging causes of death, namely drug overdoses, suicide and liver disease."