Campbell, a financial services manager, has been mayor since 2005. His current term would run through 2012.
The paper says Campbell wrote a letter to the city and the City Council, saying he wants to focus on his health and spend more time with his high-school-age daughters.
Said the paper:
Campbell wrote that he was diagnosed with nonulcer dyspepsia along with irritable bowel syndrome with visceral hyperalgesia. He has been working with his personal physician, gastroenterologist, been to the Mayo Clinic and has visited the emergency room about 20 times during this time period, according to the letter.