Boston Federal Reserve President Eric Rosengren,  who was recently caught up in a trading scandal, is set to retire on Thursday over medical concerns.

In a letter to Federal Reserve Chairman Jerome Powell that was released Monday, Rosengren said that his kidney functions have declined significantly and that he qualified for a kidney transplant list in June 2020.

Rosengren explained that the stress of the job has exasperated his health problems, necessitating a retirement that is nine months ahead of schedule. Rosengren was due to retire in June 2022 when he reached the mandatory retirement age of 65.

"It has been an honor to serve at the Federal Reserve for 35 years and in this role for 14 – and to be constantly engaged in pursuing the economic and financial well-being of our country and New England," said Rosengren in his letter.

Prior to his announcement, Rosengren was caught up in scandal after the Wall Street Journal and other outlets reported that he was involved in trading asset types that were being bailed out by the Fed last year.

Rosengren was reported to own stakes in four separate real estate investment trusts and disclosed multiple purchases and sales in multiple security types. Rosengren defended his activities as within Fed ethics guidelines, but his previous warnings about an overheating housing market and advocacy for a tapering off of asset purchases gave them an uncomfortable appearance of a conflict of interest. 

There was no mention of the scandal allegations in Rosengren's retirement announcement. Other Fed officials caught up in the scandal include Powell and Dallas Fed President Fred Kaplan.

Rosengren’s Fed colleagues praised his service to the central bank in their own statements. Chairman Powell praised Rosengren's "three decades of dedicated public service" and his "relentless focus" in creating a more stable financial system. He added that the retiring Boston chief would be missed.

Dr. Christina Paxson, the president of Brown University and chair of the bank’s board of directors, also highlighted Rosengren's work, his focus on "Main Street economic issues" and his "rare" combination of leadership traits.

Rosengren first began his career at the Boston Fed in 1985, eventually rising to become president of the bank in July 2007.