Singer-songwriter Carly Simon has revealed in a letter to fans that she has been diagnosed with Parkinson's disease, adding new detail to her earlier account of the illness by describing how it first emerged as worsening mobility problems she initially blamed on recovery from joint surgery. The 83-year-old Rock & Roll Hall of Fame inductee said she had trouble standing from low chairs and couches after arthritis in both knees and one hip led to three joint replacements, only for her mobility to keep deteriorating rather than improve, which eventually led to the Parkinson's diagnosis.

Simon, best known for "You're So Vain", said the condition affects her unpredictably, with some days leaving her too exhausted to function and others allowing her to think, work and feel more like herself. She also disclosed recent treatment for basal cell carcinoma on her face, which was successfully removed, and said the quiet period prompted by these health issues allowed her to finish a new album, Comes in Waves, out 14 August and her first in nearly 20 years since 2009's Never Been Gone; it was recorded at her Martha's Vineyard home with her children Ben and Sally Taylor involved, and lead single "Howl" is already out.