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LOS ANGELES (AP) -- The Los Angeles County coroner says socialite Casey Johnson's death was related to diabetes.

RELATED VIDEO: Casey Johnson's autopsy results

The coroner announced Thursday that the death of the Johnson & Johnson heiress was caused by diabetic ketoacidosis — a life-threatening condition caused by lack of insulin and sky-high blood sugar.

RELATED: See more photos of Casey Johnson

The coroner conducted Johnson's autopsy Jan. 5. Her body was found a day earlier in her Los Angeles home.

The 30-year-old daughter of New York Jets owner Robert "Woody" Johnson lived a party life. In December, she announced her engagement to bisexual reality TV star Tila Tequila.

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