The cause of death of actress Carrie Fisher, best known for her role as Princess Leia in the ‘Star Wars’ franchise, has been determined as sleep apnea and other factors, the Los Angeles County Coroner’s Office said in a statement on Friday.

Fisher died on 27 December 2016, after going into cardiac arrest on a flight from London to Los Angeles on 22 December. She was 60. The Medical Examiner’s office revealed on Friday that other conditions leading to the Star Wars actress’ death were atherosclerotic heart disease and drug use.

According to the press release, Fisher’s cardiac arrest was caused by multiple drug intake, with ‘significance not ascertained.’ The manner of Fisher’s death has been ruled undetermined.

‘My mom battled drug addiction and mental illness her entire life. She ultimately died of it,’ Fisher’s daughter, Billie Lourd, said in a statement to ET. ‘She was purposefully open in all of her work about the social stigmas surrounding these diseases.’

‘She talked about the shame that torments people and their families confronted by these diseases. I know my Mom, she’d want her death to encourage people to be open about their struggles,’ Lourd continued. ‘Seek help, fight for government funding for mental health programs. Shame and those social stigmas are the enemies of progress to solutions and ultimately a cure. Love you Momby.’

Fisher’s death certificate was released in January, listing ‘cardiac arrest/deferred’ as the cause of death.

Six months after her death, Fisher is still being remembered by family, friends and fans. See Mark Hamill’s touching tribute to the actress during Sunday’s Tony Awards’ In Memoriam segment in the video below.