Carrie Fisher's true cause of death revealed

Almost six months after her sudden death, coroner's officials in Los Angeles have revealed that Carrie Fisher died from sleep apnea and a combination of other factors.

Among the factors was a buildup of fatty tissue in the walls of her arteries, while the Star Wars actress also showed signs of having taken multiple drugs - however, investigators weren't able to determine whether they actually contributed to her death in December.

They said in a statement that unfortunately, because a number of factors contributed to her passing, investigators were not able to pinpoint an exact cause of death, so it will be officially listed as "undetermined".

Carrie died in December last year, one day before her mother passed away. Photo: Getty

Sleep apnea is a condition where a person's breathing pauses during sleep, these can be for a matter of seconds, or for several minutes.

Fisher was just 60 when she passed away after suffering a medical emergency on an international flight on December 23. Her mother, much-loved movie star Debbie Reynolds, died the following day.

The actresses were laid to rest together at Forest Lawn-Hollywood Hills, a cemetery where a number of celebrities are buried.

She was most famous for her role in Star Wars. Photo: Getty

Carrie's brother Todd Fisher, said he wasn't surprised by the results and added that his family didn't want a coroner's investigation of his sister's death.

"We're not enlightened. There's nothing about this that is enlightening," he said.

"I would tell you, from my perspective that there's certainly no news that Carrie did drugs," Todd Fisher said. He noted that his sister wrote extensively about her drug use, and that many of the drugs she took were prescribed by doctors to try to treat her mental health conditions.

Carrie was open about her long battle with drug addiction and mental illness. It started when she smoked pot at 13, and she began using LSD by 21, before being diagnosed as bipolar at 24. She was treated with electroshock therapy and medication.

Carrie is due to appear in the next Star Wars movie. Photo: Getty

"I am not shocked that part of her health was affected by drugs," her brother Todd said.

He said his sister's heart condition was probably worsened by her smoking habit, as well as the medications she took. "If you want to know what killed her, it's all of it," he said.

Todd said it was difficult to blame doctors who treated his sister because they were trying to help her.

"They were doing their best to cure a mental disorder. Can you really blame them?" he said. "Without her drugs, maybe she would have left long ago."

Carrie made her feature film debut opposite Warren Beatty in the 1975 hit Shampoo. She also appeared in Austin Powers, The Blues Brothers, Charlie's Angels, Hannah and Her Sisters, Scream 3 and When Harry Met Sally.

She will appear one last time as Princess Leia Organa in the eighth installment of the StarWars franchise, TheLast Jedi, which will be released in December.

- Withadditional reporting by AAP

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