The sudden and tragic death of pop star Whitney Houston saddened fans the world over last month after she was found unresponsive in her bathtub on the night before the Grammys. Her death was initially ruled as a drowning, but an autopsy report released today shows that cocaine use and heart disease were contributing factors to her death.

The toxicology report also found marijuana, an anti-anxiety medication, a muscle relaxant and an anti-histamine in Houston’s system, according to L.A. County Coroner spokesman Craig Harvey. Those drugs were not found to play a role in her death.

“We are saddened to learn of the toxicology results, although we are glad to now have closure,” Patricia Houston, the singer’s sister-in-law and manager said today.

In 2005 Houston and her family–husband and R&B singer Bobby Brown and their daughter Bobbi Christina–were the subject of a reality show on Bravo called “Being Bobby Brown” which showed a very different side of the star than her fans were used to seeing. Clearly under the influence of substances, her behavior was erratic and worrisome to those closest to her. But after checking into rehab in 2011 and making an effort to get clean, Houston had her friends and family convinced that the worst of her drug use was behind her, as Patricia Houston told Oprah Winfrey in an interview this month.

The day after Houston’s death, Jennifer Hudson paid tribute to the golden-voiced singer at the Grammy awards, creating a highlight of the night.