In its first results since its insurance unit CEO was fatally shot in New York City, UnitedHealth Group reported Thursday weaker-than-expected fourth-quarter revenue, prompting its shares to fall in early morning trading despite quarterly profit beating projections.

UnitedHealth reported fourth-quarter results on Thursday that reflected persistent challenges for the health insurance sector.

In his first public comments since one of his executives was shot to death, UnitedHealth Group CEO Andrew Witty said the healthcare system “needs to function better.”

UnitedHealth posted a better-than-expected fourth-quarter profit, but a nagging rise in medical costs and care utilization surprised Wall Street.

UnitedHealth Group Inc. reported fourth-quarter profit that surpassed Wall Street’s expectations in its first financial statement since a top executive was killed in New York last month.