By Amina Niasse and Ross Kerber

NEW YORK / BOSTON, Jan 8 (Reuters) - UnitedHealth Group UNH.N shareholders on Wednesday said they requested the company prepare a report on the costs and public health impact related to its "practices that limit or delay access to healthcare."

If the proposal makes it to a vote at the company's annual meeting it would raise a charged topic after a senior executive was gunned down in Manhattan last month.

A spokesperson for UnitedHealth said the company will respond to shareholder proposals for its 2025 proxy statement once it files the document that serves as an agenda for its annual meeting, which has not yet been scheduled. In recent years, the company has issued its proxy in April ahead of a June annual meeting.

Those who filed the resolution include religious groups led by the Sisters of the Holy Names of Jesus and Mary of Quebec, and Trillium Asset Management.

The group proposed an analysis of how prior authorization, or approval required by an insurer before a patient can receive medical care, and denials of medical services lead patients to forgo treatment.

“The pattern of delays and denials of necessary medical care by UnitedHealth and other insurance companies harms more than just the patient themselves,” Wendell Potter, president of the Center for Health & Democracy and a former Cigna CI.N executive, said in a statement sent in support of the resolution by the Interfaith Center on Corporate Responsibility.

UnitedHealth runs the country's largest health insurer, UnitedHealthcare, as well as pharmacy benefit manager Optum and medical practices.

The killing of UnitedHealthcare CEO Brian Thompson in December galvanized criticism of U.S. health insurers, with swarms of patients describing delayed or denied care and accusing companies of using deceptive practices.

Luigi Mangione, 26, who was accused of killing Thompson, pleaded not guilty in a New York court in December after receiving thousands of dollars in public donations shortly after his arrest.

In a December statement, UnitedHealth said it approves and pays for an average of 90% of medical claims submitted.

"Highly inaccurate and grossly misleading information has been circulated about our company’s treatment of insurance claims," UnitedHealth said.

UnitedHealth CEO Andrew Witty in a message to employees described Thompson as "one of the good guys," adding the company would continue to service the most vulnerable Americans.

(Reporting by Amina Niasse in New York and Ross Kerber in Boston; editing by Caroline Humer and Bill Berkrot)

((amina.niasse@thomsonreuters.com;))