01:31 PM EST, 12/13/2024 (MT Newswires) -- UnitedHealth Group ( UNH ) Chief Executive Andrew Witty said that the US health care system is "flawed" and needs to be fixed.

Witty mourned the death of Brian Thompson, CEO of the company's insurance business, UnitedHealthcare. Thompson was fatally shot in New York last week. Luigi Mangione is the suspect arrested in connection with Thompson's killing, according to media reports.

"The etching on the bullet casings found at the site suggests that (dissatisfaction) with health insurance coverage denials may be a motivating factor," Macquarie said in a note to clients earlier this week.

Mangione was reportedly not insured by UnitedHealth ( UNH ).

"We know the health system does not work as well as it should, and we understand people's frustrations with it," Witty wrote in a New York Times opinion piece published Friday. "No one would design a system like the one we have. And no one did. It's a patchwork built over decades."

Thompson supported ideas that were meant to make health care more affordable and transparent, Witty said.

"Health care is both intensely personal and very complicated, and the reasons behind coverage decisions are not well understood," Witty wrote. "We share some of the responsibility for that."

Witty highlighted the need for a collective effort to better explain how decisions about insurance covers are made. "Behind each decision lies a comprehensive and continually updated body of clinical evidence focused on achieving the best health outcomes and ensuring patient safety."

UnitedHealth ( UNH ) shares were up 1.5% in Friday afternoon trade, but have lost 14% in value so far this month.

The company is "willing to partner with anyone" to help deliver high-quality care and lower costs, Witty said. "Clearly, we are not there yet."

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