"We are grateful for Andrew's stewardship of UnitedHealth Group, especially during some of the most challenging times any company has ever faced," Hemsley said in a release. The company said its decision to pull its guidance was partly due to higher medical costs, which dragged down other insurance stocks. Shares of both CVS Health dropped nearly 3% and shares of Elevance Health fell more than 3%, while Humana's stock slid more than 2% and shares of Cigna lost more than 1%. Andrew Witty, CEO of UnitedHealth ...