UnitedHealth Group CEO Andrew Witty will step down from his role at the top of the company due to personal reasons, the healthcare giant announced Tuesday morning. | UnitedHealth Group CEO Andrew Witty will step down from his role at the top of the company due to personal reasons,

Witty’s departure was surprising, though it follows a sharp downturn in the healthcare juggernaut’s financial outlook. He is being replaced by Stephen Hemsley, the chair of UnitedHealth’s board and a previous chief executive.

The health care conglomerate is facing mounting financial problems – and ongoing consumer anger over high costs and denied claims.