The official cause of Sinead O’Connor’s death has been revealed. The Irish singer-songwriter, who was found dead in her apartment on January 7, passed away due to natural causes related to cardiac arrest, the New York City Medical Examiner’s Office confirmed to E! News. According to the report, O’Connor died from natural causes due to chronic drug use and pulmonary edema, which is a condition that occurs when there is excess fluid in the lungs. The medical examiner’s office also determined that no foul play was involved in her death. Sinead O’Connor rose to fame with her hit song ‘Nothing Compares 2 U’ in the early 1990s. She had been open about her struggles with mental health and addiction over the years, and had publicly spoken about her efforts to get sober. Her death at the age of 74 has left fans and friends shocked and saddened.