Racial disparities in U.S. overdose death rates increased significantly in the first year of the pandemic, according to new research by the Centers for Disease Control and Prevention (CDC).

The deaths were largely driven by illicit fentanyl, according to the CDC.

Overdose rates spiked much more among Black, American Indian and Alaska Native people, compared with white people, STAT reports. Overall overdose deaths increased 30% from 2019 to 2020. Overdose death rates increased by 44% among Black people, 39% among American Indian and Alaska Native people and 22% among people who are white, Asian or Pacific Islander or Hispanic.

“The increase in overdose deaths and widening disparities are alarming,” CDC Acting Principal Deputy Director Dr. Debra Houry, M.D., M.P.H., said in a news release. “Overdose deaths are preventable, and we must redouble our efforts to make overdose prevention a priority.” In a briefing with reporters, Houry said the disparities “may partly be due to health inequities like unequal access to substance use treatment and treatment biases.”