The rate of premature death throughout the United States varies depending on race and ethnicity. And whites, along with American Indian and Alaskan populations, are experiencing larger increases in premature mortality than other races, according to a study released Thursday. That increase is due, in large part, to drug use.

The study, conducted by researchers at the National Cancer Institute (NCI), the National Institute on Drug Abuse and the University of New Mexico College of Nursing, analyzed overall death rates in the U.S. from 1999 to 2014 to determine premature mortality by population. Premature death is defined as death that occurs anywhere from the ages of 25 to 64.

Researchers found that early death rates increased as much as five percent in whites, American Indians and Alaskans aged 25 to 30. That increase is comparable to the spike seen during the AIDs epidemic in the U.S. In contrast, premature death rates among Hispanics, blacks, and Asian/Pacific islanders declined.

The decline among those populations was attributed to fewer deaths from cancer, heart disease and HIV. The increase seen in white populations was likely due to escalated drug use and more overdoses, according to the researchers.

“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,” said Meredith Shiels of the Division of Cancer, Epidemiology and Genetics at the NCI and the lead author of the study.

Opioid use is nearing crisis proportions in many parts of the U.S., and more whites than any other race have been affected. More than 23,000 whites died of an opioid overdose in 2014 as compared with 2,200 blacks and 2,100 Hispanics, according to the Kaiser Family Foundation. Some of the states with the highest rates of overdose deaths are also states with the largest white populations. West Virginia has the fourth largest white population in the U.S. and had the highest rate of drug overdose deaths in 2015, according to the Centers for Disease Control and Prevention.

Although the study saw improvements in premature mortality in many populations, overall premature death rates still remained higher for black men and women than for whites.