Bernard Tyson, CEO of Kaiser Permanente, passes away 'unexpectedly' in his sleep at age 60

Bernard J. Tyson, the chairman and CEO of the health plan provider Kaiser Permanente, passed away in his sleep on Sunday.

One day earlier, Tyson spoke at a tech gathering in Oakland, California, called AfroTech where he appeared to be in good spirits, sharing photos on Twitter. The health care executive was 60 years old.

Kaiser Permanente issued a statement late Sunday saying, "On behalf of our Board of Directors, employees and physicians, we extend our deepest sympathies to Bernard's family during this very difficult time." The company said Tyson "unexpectedly passed away early today in his sleep."

The company, which offers the nation's largest not-for-profit health plan, called Tyson "an outstanding leader, visionary and champion for high-quality, affordable health care for all Americans."

He became the head of Kaiser Permanente in 2013 and has worked at the company for over 30 years. He also served on the board of directors for the American Heart Association and SalesForce, according to his bio on the company's website.

During his time as CEO, the company's health care memberships grew from 9 million to 12.3 million. Revenue grew from $53 billion in 2013 to more than $80 billion, according to the company website.

The San Francisco Bay native is survived by his wife, Denise Bradley-Tyson, and three sons; Bernard Jr., Alexander and Charles.

The company says that its board of directors has named Gregory A. Adams as interim chairman and CEO. Adams previously served as the nonprofit's executive vice president.

"The board has full confidence in Greg Adams' ability to lead Kaiser Permanente through this unexpected transition," the company said in a statement.

This article originally appeared on USA TODAY: Kaiser Permanente CEO Bernard Tyson dies 'unexpectedly' at 60