Last November, DJ and producer i_o died suddenly at age 30. His cause of death has now been disclosed by the Los Angeles County Medical Examiner, as EDM.com and Billboard point out. According to the medical examiner’s report, i_o, whose real name was Garrett Lockhart, died of natural causes related to Hashimoto’s Thyroiditis—an autoimmune disorder that involves chronic thyroid inflammation.

i_o’s family released a statement to EDM.com regarding the cause of death announcement. According to the family, i_o had a “sudden and fatal arrhythmia.” They added:

After 5 months of testing, the conclusion is that, while Garrett did suffer from depression and anxiety, he did not take his own life. It is our hope that Garrett’s premature death can be used to create and normalize conversations surrounding mental health issues, realizing there may be underlying disease of conditions requiring medical attention.

Over the past few years, i_o released three EPs that became an album called 444. In 2019, he appeared on Grimes’ song “Violence” from her last album Miss Anthropocene.