Amyotrophic lateral sclerosis, a progressive disease, “has made it impossible to sing and not easy to speak,” a statement from her publicists said. “But it will take a lot more than ALS to silence this icon.”

A documentary about Flack’s life is set to debut at a film festival in New York next week. It will air on PBS television in the United States in January. Flack, 85, also is releasing a children’s book in January.

ALS breaks down nerve cells in the brain and spinal cord that make muscles work, leading to progressive paralysis and death.

Flack had several No. 1 hits in the 1970s and produced 20 studio albums. She won four Grammys and was honoured with a lifetime achievement award in 2020.

The singer also was the first artist to win two consecutive record of the year trophies in 1973 for “First Time I Ever Saw Your Face” and in 1974 for “Killing Me Softly with His Song.”