U.S. Sen. Johnny Isakson, R-Ga., announced Wednesday he will leave office early due to a battle with Parkinson’s disease. 

Isakson, 74, will resign on Dec. 31 after more than 40 years in elective office at the state and federal levels. 

“I am leaving a job I love because my health challenges are taking their toll on me, my family and my staff,” Isakson said in a news release. “My Parkinson’s has been progressing, and I am continuing physical therapy to recover from a fall in July. In addition, this week I had surgery to remove a growth on my kidney.

“With the mounting health challenges I am facing, I have concluded that I will not be able to do the job over the long term in the manner the citizens of Georgia deserve. It goes against every fiber of my being to leave in the middle of my Senate term, but I know it’s the right thing to do on behalf of my state.”

Under state law, Gov. Brian Kemp will appoint a temporary successor to Isakson to serve in the Senate next year. The appointee then could run on the same ballot next year as Georgia’s other U.S. senator, Republican David Perdue, but would serve only until the end of Isakson’s term in 2022 before having to run again for a full six-year term.

“No one embodies the heart and soul of Georgia more than Johnny Isakson,” Kemp said. “Our state and country have been immeasurably blessed by his leadership in the Georgia General Assembly, U.S. House and U.S. Senate.”

Isakson is the only Georgian ever elected to the state House, state Senate, U.S. House and U.S. Senate. In 2016, he also became the first Georgia Republican elected to a third term in the U.S. Senate. 

Isakson was diagnosed with Parkinson’s disease in 2013. Last month, he fell in his Washington, D.C., apartment, suffering four fractured ribs and a torn rotator cuff. On Monday, he had surgery to remove a two-centimeter renal cell carcinoma from one of his kidneys.

Isakson spent more than three decades in the real estate business in Cobb County, overlapping with the early years of his political career. Besides serving as a state legislator and member of Congress, he was chairman of the Georgia Board of Election.

In Congress, Isakson became known as a strong advocate for America’s veterans, sponsoring legislation aimed at improving health care in the Veterans Administration hospital system. He is currently chairman of the Senate Committee on Veterans’ Affairs.

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