A man walks past a homeless encampment beneath an overpass in Los Angeles, California.
CNN  — 

The deaths of homeless people in Los Angeles doubled from 2013 to 2018, according to a report released Tuesday by the Los Angeles County Department of Public Health.

The number of homeless deaths increased from 536 in 2013 to 1,047 in 2018, the report said. The overall death rate increased by over a third during that time, when taking the increase in the homeless population into account.

Drug and alcohol overdoses were the largest contributing factor to death rate increase, the report said.

From 2016 to 2018, the overdose death rate for the homeless was 26 times higher than the general population, figures show.

“This alarming increase in homeless deaths requires immediate action to improve the care for our most vulnerable populations,” Dr. Barbara Ferrer, director of the county health department, said in a news release.

The top cause of death was coronary heart disease, which accounted for nearly a quarter of those deaths during the six-year span. Other leading causes included traffic injuries, homicide and suicide.

The report also found that homeless people died on average 22 years earlier than the general population.

“Homelessness can have a devastating impact on a person’s health and well-being, and we need to better understand the underlying causes that contribute to our County’s high mortality rate among those who are experiencing homelessness,” Supervisor Hilda L. Solis said.

The report recommended several actions, including establishing a team to review homeless deaths to better understand the circumstances.

The county’s homeless population had increased to almost 60,000 this year despite major investment to combat the crisis, according to a report released earlier this year by the Los Angeles Homeless Services Authority. That is an increase of 12% compared to the previous year,the report said.

The city of Los Angeles – where the bulk of the county’s homeless population resides – saw a 16% rise in homelessness, to 36,300 people, the report said.

CNN’s Darran Simon and Madeline Holcombe contributed to this report.