麻豆传媒

In patients with complicated diverticulitis initially treated nonsurgically, high rates of interval resection were not associated with reduced rates of emergency surgery or death, a large Swiss-Scottish cohort study found.

Marco von Strauss und Torney, MD, of St. Clara Hospital and University Hospital Basel in Switzerland, and colleagues conducted a secondary cohort analysis of 13,861 patients in Switzerland and 5,129 patients in Scotland with complicated diverticulitis. Of these, 3,280 (24%) in Switzerland and 231 (5%) in Scotland underwent an interval resection to forestall adverse outcomes.

The study, published online in , found that despite a nearly five-fold difference in interval resections, the rate of emergency surgery or death was 5% in both countries.

The findings support the recent movement toward more conservative management of diverticulitis and careful selection of patients for , the researchers said. "Our study results challenge the appropriateness of recommendations for prophylactic surgery after a successfully nonoperatively managed episode of complicated diverticulitis, as, for example, those by the [] and the ," von Strauss und Torney and co-authors wrote.

They noted that diverticulitis can cause life-threatening sepsis but recurs in only a small number of patients, and national guidelines on interval resection for preventing recurrence are inconsistent. Diverticulitis accounts for almost 220,000 per year in the U.S., and while most cases are uncomplicated, 10-15% of patients present with the complicated form -- defined as the presence of intra-abdominal abscess, fistula, free perforation, or hemorrhage.

A trend to increased diagnosis of this disease in has been reported, the team noted. Although U.S. and German guidelines favor interval colonic resection in light of a perceived high risk of recurrence, U.K. guidelines do not.

Asked for her perspective, Anne F. Peery, MD, MSCR, of the University of North Carolina at Chapel Hill, who was not involved with the study, called it "important and practical," and said it will likely "change guidelines, prevent unnecessary surgeries, and help patients to make a more informed decision."

Based on this research, "we can advise patients with complicated diverticulitis managed without surgery that their risk of future emergency surgery or death from diverticulitis is 5% in 5 years," Peery told 麻豆传媒. "An elective resection of the colon does not decrease that risk and therefore should not be a reason to consider surgery. Instead, patients may elect for an elective resection to reduce the risk of recurrence. "

In addition, she pointed out, the risk of readmission for diverticulitis in the study was 36-37% over 5 years, and this does not include all of the recurrences managed in the outpatient setting.

"An elective resection is not without risks," Peery continued. "Elective surgery was associated with 1% mortality, which is a good estimate consistent with the literature. Also of note, an elective resection for diverticulitis does not guarantee a cure. The risk of recurrent diverticulitis after an elective segmental resection is 15% in 5 years."

Study Details

For the study, the researchers obtained data from Swiss and Scottish healthcare databases on patients diagnosed from January 1, 2005, to December 31, 2015. Women made up about 50% of the total cohort (6,967 women in Switzerland and 2,804 in Scotland).

Scottish patients were more likely to be cared for in hospitals with higher overall patient volume (96.1% vs 83.1%) and a higher caseload for diverticulitis (88.5% vs 72.6%) The median age categories were 70-74 in Scotland and 65-69 in Switzerland. All patients had an index episode of complicated acute diverticulitis, which was managed nonoperatively.

The primary endpoint of emergency readmission requiring surgery or leading to inpatient death was observed in 698 Swiss patients (5%) and 255 Scottish patients (5%), for an odds ratio of 0.98 (95% CI 0.81-1.19), the researchers reported. Elective interval colonic resection was performed in 3,280 Swiss patients (23.7%) with a median follow-up of 53 months (interquartile range 24-90 months) and in 231 Scottish patients (4.5%) with a median follow-up of 57 months (27-91 months).

Death after urgent readmission for recurrent diverticulitis occurred in 104 patients (0.8%) in Switzerland and 65 patients (1.3%) in Scotland. Apart from comorbidity, none of the investigated confounders had a significant association with outcomes.

"Mortality was lower in Switzerland, but absolute numbers in both countries were very low and almost identical in per-head-of-population terms," the authors wrote. "This difference might be associated with older age and greater comorbidity in the Scottish cohort or, in a limited way, with higher elective resection rates in Switzerland, but it is more likely to be associated with a higher rate of diagnosis in Switzerland."

Study limitations, von Strauss und Torney and co-authors said, included the lack of granularity in healthcare administrative data and variations in coding and classification of hospital-based outcomes over time. In addition, relevant confounders such as overweight or use of immunosuppressive medication were not available in the databases nor was information on previous patient history, and definitions of some variables differed in the two countries.

The researchers noted that the difference in the incidence of complicated diverticulitis between the two healthcare systems and the difference in mean age was probably associated with the greater availability of imaging in Switzerland than in Scotland, a bias that would potentially enrich for relatively more severe cases in the Scottish cohort. In addition, the team said, the study had no information on outpatient management, yet ongoing symptoms are an important indication for elective interval surgery in selected patients.

Comment