After the health insurer pulled its outlook for the year, analysts rushed to cut their predictions on the stock.

Even UnitedHealth will struggle to overcome parasitic medical costs that Warren Buffett once called a tapeworm eating away at U.S. economic competitiveness. The $300 billion healthcare conglomerate reinstalled Chairman Stephen Hemsley as CEO and yanked its financial guidance.

UnitedHealth Group Incorporated's stock faces a steep decline amid leadership turmoil, regulatory pressures, and rising costs. Click to read why UNH is a Hold.

Nvidia and AMD extend gains after the chip makers sign deals with Saudi Arabia, UnitedHealth claws back some losses from the previous session, and American Eagle Outfitters slumps after pulling guidance for the rest of the fiscal year.

The White House unveiled what it says is $600bn worth of defence and artificial intelligence deals with Saudi Arabia, UnitedHealth Group shares sink to the lowest level in more than four years, and US inflation fell to 2.3 per cent in April. Plus, Nissan plans to axe 15 per cent of its global workforce and almost halve its number of plants.

Stephen J. Hemsley returned as CEO after Andrew Witty's surprising decision to leave the insurance giant. UnitedHealth's stock fell 17% on Tuesday.

Surging medical costs and regulatory changes hit UnitedHealth, but rivals such as Humana and CVS look better positioned.