Nelson H. Cruikshank, 83, a founder and former president of the National Council for Senior Citizens who also was an adviser on aging to President Jimmy Carter, died of congestive heart failure June 19 at a nursing home in Philadelphia.

In the 1950s and early 1960s, Mr. Cruikshank was the top expert in the AFL-CIO on Social Security and related issues. In 1961, he helped organize the National Council for Senior Citizens to campaign for passage of Medicare, the program that provides health care for the elderly. The legislation was passed in 1965 during the Johnson administration.

In 1969, Mr. Cruikshank became president of the NCSC, which today has 4.5 million members. He left the organization in 1977, when Carter appointed him chairman of the Federal Council on Aging and the White House adviser on aging.

As the president's adviser, Mr. Cruikshank sometimes opposed administration policy. In 1979, for example, he told the House Committee on Aging that limits on Social Security benefits proposed by the Carter White House were "ill-advised" and "trumped up."

He said at the time that he was speaking for himself and not for the administration, which he said had informed him "that I am free to express disagreement as long as I make clear the distinction between what are my own views and what are the administration's positions."

After leaving the White House in 1980, Mr. Cruikshank returned to the NCSC and served as president emeritus until his death. He moved to Philadelphia in 1984.

A native of Bradner, Ohio, Mr. Cruikshank graduated from Ohio Wesleyan University. He earned a master's degree in divinity from the Union Theological Seminary in New York.

He moved to the Washington area in the 1930s. He worked for the old Farm Security Administration and the old War Manpower Commission before joining the American Federation of Labor in 1944 as the director of social insurance.

From 1951 to 1952, Mr. Cruikshank was the director of the European Labor Division of the Marshall Plan in Paris. He returned to the AFL in 1953 and became the director of the department of social security. The AFL merged with the Congress of Industrial Organizations in 1955. Mr. Cruikshank retired from the AFL-CIO in 1965.

During the late 1960s, he was a visiting professor at Michigan State and Pennsylvania State universities and the University of Michigan.

His wife Florence died in 1967. Survivors include one daughter, Alice Hoffman of Wynnewood, Pa.