Acute diverticulitis, a leading cause of U.S. hospital admissions, is associated with an increased risk of subsequent colorectal cancer (CRC), according to a large population-based study. "We found that there was an almost 2-fold greater risk of colorectal cancer within one year after first presentation of diverticulitis compared to those without diverticulitis," Dr. Gregory S. Cooper of Case Western Reserve University, in Cleveland, Ohio, told Reuters Health by email. The incidence of acute diverticulitis is increasing, he and his colleagues note in Diseases of the Colon and Rectum. However, despite an apparent connection to CRC, "Screening every patient for CRC after an episode of acute diverticulitis has remained controversial, especially for cases of uncomplicated diverticulitis." To shed more light on the matter, the researchers examined data from 2015 to 2020 on 31 million patients drawn from 26 healthcare systems across the U.S. Of these, more than 932,000 had a first-ever episode of diverticulitis, for an overall incidence of 2.94%. Moreover, 5,200 out of 916,850 diverticulitis patients were diagnosed with first-ever CRC within one year after the diagnosis of first-ever diverticulitis. This gave a prevalence of 0.57% compared to 0.31% in those without a history of diverticulitis. Most (92.3%) of the post-diverticulitis CRC cases were diagnosed within the first six months after diverticulitis. The risk of CRC was significantly increased following diverticulitis in women, men, African Americans, Caucasians, and in those aged 18 to 65 years, but not in Asians or seniors. "The findings support colonoscopy after the acute diverticulitis resolves, typically 6 to 8 weeks," concluded Dr. Cooper. —David Douglas Source
