The 75-year-old former investor, who is in his fourth year of a 150-year prison sentence, was back in prison after being hospitalized at the Duke University Medical Center last month.
Madoff is also suffering from stage-four kidney disease, but is not undergoing dialysis, he confirmed in an email.
Prison officials declined to comment on Madoff's health, but confirmed he has been returned to the Butner Federal Correctional Complex, 25 miles northwest of Raleigh.
Madoff was convicted for running the largest investment fraud scheme in U.S. history, swindling investors out of $17 billion in 2008.
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