UnitedHealth has revealed that 190 million Americans had their personal and healthcare data stolen in the Change Healthcare ransomware attack, nearly doubling the previously disclosed figure.

The number of individuals confirmed to be affected by the data breach is almost double the company's previous estimate.

The attack, originally thought to have impacted about a 100 million Americans, is even larger than originally disclosed.

The cyberattack at UnitedHealth Group's tech unit last year affected the personal information of 190 million people, the health conglomerate said on Friday, making it the largest healthcare data breach in the United States.

The cyberattack at UnitedHealth Group exposed personal information of 190 million people, leading to a $22 million ransom payment in bitcoin.