UnitedHealth Group upped financial guidance for a second time this year after posting second-quarter results that solidly beat analysts' expectations.

The Minnetonka-based health care giant reported Friday a second-quarter profit of $5.07 billion on revenue of $80.33 billion. The earnings were up about 19% over the same period last year.

The results echoed numbers from the first quarter when UnitedHealth Group also raised its full-year outlook after reporting earnings of more than $5 billion.

"Customers are responding as we build on our five growth pillars, enabling us to move into the second half of 2022 with strong momentum serving ever more people more deeply," Andrew Witty, UnitedHealth Group chief executive, said in a statement.

UnitedHealth Group operates UnitedHealthcare, which is the nation's largest health insurer, as well as a fast-growing division for health care services, Optum.

Second-quarter results were helped by lower-than-expected medical costs as well as growth at Optum that "continues to impress," wrote Kevin Fischbeck, an analyst with Bank of America, in a BofA Global Research report.

OptumCare, the division that runs clinics and outpatient health care centers, continues to get bigger, Fischbeck noted. This year, it closed on the purchase of Atrius Health, a large physician group in Massachusetts, and also acquired a large multi-specialty practice in Houston called Kelsey-Seybold "for about $2 [billion]," he wrote.

UnitedHealth Group did not immediately comment on terms of the deal.

"Optum is aligned with Kelsey-Seybold's care delivery model which brings coordinated, value-based care to patients and employers," the company said in a statement. "We have a shared vision of supporting high-quality care with better experiences for patients and providers at a lower total cost of care."

At the end of the second quarter, 45.78 million people in the U.S. were enrolled in coverage from UnitedHealthcare, up nearly 1% from the first quarter.

Adjusted earnings per share of $5.57 beat analyst estimates by 37 cents, according to data from Seeking Alpha. The adjusted numbers exclude intangible amortization and other items unrelated to underlying business performance, the company said.

For the year, UnitedHealth Group now expects adjusted earnings of $21.40 to $21.90 per share, up 20 cents at both the low and high end of the range from the previous guidance.

In October 2021, UnitedHealth Group employed more than 333,000 full-time, part-time, temporary and seasonal employees, according to a regulatory filing. More than 113,000 workers at the time were outside the U.S. — the company is a large operator of hospitals and clinics in South America.

UnitedHealth Group employs about 18,000 people in Minnesota. The company is the state's largest by revenue.