UnitedHealth Group will spend nearly $8 billion in cash to add a health care technology company to its growing Optum business.

UnitedHealth said Wednesday that it will add Change Healthcare to its OptumInsight segment and boost its ability to provide data analytics and revenue cycle management support, among other offerings.

Minnetonka, Minnesota-based UnitedHealth brings in most of its revenue through a health insurance business that covers about 48 million people. But its Optum segment generates bigger profit margins and provides a growing portion of the company's operating earnings.

That business runs surgery centers, clinics and one of the nation's largest pharmacy benefit management operations. It also provides technology services and support through OptumInsight.

OptumInsight accounts for only about 3% of UnitedHealth's revenue, but it also generates an operating profit margin of around 25%, Mizuho Securities analyst Ann Hynes said in a research note. She added that she views the Change deal positively.

UnitedHealth will pay $25.75 in cash for each share of Change Healthcare in a deal the companies expect to close in the second half of the year.

It still needs approval from Change shareholders and regulators. Private equity funds tied to The Blackstone Group own a roughly 20% stake in the Nashville company, and they have already voted in favor of the deal.

Shares of UnitedHealth Group Inc. rose slightly to $346.80 in mid-morning trading Wednesday, while Change Healthcare jumped 31% to $23.93.