Apple CEO Steve Jobs takes medical leave until June

SAN FRANCISCO -- Apple CEO Steve Jobs is taking a medical leave of absence until the end of June because his health problems are "more complex than originally thought," he said in an e-mail to company employees Wednesday.

But in recent months the 53-year-old Jobs, a pancreatic cancer survivor, has lost considerable weight. That has raised concerns not only about whether the cancer has returned, but about his ability to forcefully lead during an economic downturn — especially a company like Apple, which specializes in premium-price consumer products.

"Unfortunately, the curiosity over my personal health continues to be a distraction not only for me and my family, but everyone else at Apple as well," Jobs said in the e-mail. "As CEO, I plan to remain involved in major strategic decisions while I am out," he said. "Our board of directors fully supports this plan."

Apple's chief operating officer, Tim Cook, will take over Jobs' day-to-day responsibilities while he is on leave. Cook, who left Compaq Computer in 1998 to join Apple, filled in as interim Apple CEO when Jobs battled pancreatic cancer.

Jittery investors reacted immediately to Jobs' medical leave, sending Apple shares down 7%, to $79.30, in after-hours trading — its lowest in two years. A year ago, the stock was trading at just under $200.

Last week, Jobs had tried to soothe investors' concerns about his health. He said his noticeable weight loss in recent months was the result of a treatable hormone imbalance.

Although Jobs has not elaborated on his health, a hormone imbalance is a possible consequence of cancer treatment, some medical specialists say. Concern over Jobs' health has led some critics to question whether he and Apple are being fair to shareholders by not disclosing more information.