Rates of fatal drug overdoses are now higher in urban counties than in rural areas, according to a new analysis from the National Center for Health Statistics.

Between 2007 and 2015, drug overdose death rates were higher in rural counties than in urban counties, CNN reports. Starting in 2016, drug overdose death rates were higher in urban counties.

The analysis found while urban counties had higher rates of overdose deaths involving heroin, cocaine and synthetic opioids such as fentanyl in 2017, rural counties had higher overdose death rates involving prescription opioids including morphine, codeine, hydrocodone and oxycodone.

There were 5.2 heroin-related overdose deaths for every 100,000 people in urban counties in 2017, compared with 2.9 per 100,000 people in rural counties.