A number of factors contributed to actress Carrie Fisher's death in December, the Los Angeles County coroner's office reported late Friday, including sleep apnea and heart disease. The statement also mentions drug use but doesn't specify which drugs or how long ago they were taken.

The report leaves the cause of death "undetermined" for the 60-year-old, best known as Princess Leia in the Star Wars movies.

Fisher had long battles with drug addiction and mental illness, The Associated Press reported after she died, which she had been open about in her memoirs and novels.

"She said she smoked pot at age 13, used LSD by 21 and was first diagnosed as bipolar at age 24. She was treated with electroconvulsive therapy and medication."

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