Health and Human Services Secretary Otis R. Bowen told a congressional subcommittee yesterday that he will be looking for ways to help the elderly pay for expensive nursing home care, as part of a study of catastrophic-health insurance President Reagan has ordered.

While saying that no detailed proposal has been developed, the 67-year-old Cabinet member said his mother is in a nursing home and "I am very deeply aware of that [issue], because I know who pays the bills."

Rep. Claude Pepper (D-Fla.), chairman of the House Aging subcommittee on health and long-term care, had expressed concern that the administration might be considering only coverage of long hospital stays for acute medical care.

This would help only about 1 percent of Medicare beneficiaries, while raising premiums for all, because most hospital stays are shorter than currently covered by Medicare, Pepper said. To focus on hospital costs would disregard custodial care provided at home or in a nursing home, "where the real catastrophic need exists," he said.

At present, a patient pays for the first day in the hospital, and Medicare pays for the next 59 days. Nursing home costs generally are not covered.

Reagan, in his Feb. 4 State of the Union address, directed Bowen to study how government and the private sector can provide catastrophic-health insurance to protect the elderly against financial ruin by long illness.

Bowen told the subcommittee he believes that comprehensive long-term care and catastrophic-health insurance "can be made cost-neutral to the federal government."

One proposal he has made in the past, and raised again yesterday, would create "individual medical accounts," along the lines of individual retirement accounts, to which people could make tax-deferred contributions and from which they could draw if they need nursing home care.

On another topic, the subcommittee heard a former insurance agent convicted of fraud, who appeared incognito, and a U.S. postal inspector describe how agents sell worthless or overpriced health policies to vulnerable older persons.