憩室病进展至憩室炎的几率较低

圣迭戈(EGMN)——一项最新研究显示，憩室病患者进展至憩室炎的几率实际上较低，远低于医学文献通常报道的10%~25%。

在这项研究中，加州大学洛杉矶分校的Kamyar Shahedi博士及其同事对美国退伍军人事务部大洛杉矶地区卫生保健系统1996~2011年登记的所有憩室病患者的病历进行回顾分析。研究者在排除既往诊断憩室病的病例后，查找到2,222例新诊断患者，然后从中挑出发生憩室炎的病例。2,222例憩室病患者均为退伍军人，平均年龄为67岁，98%为男性，平均体重指数为28.5 kg/m²，40%为白人，10%为黑人，8%为西班牙裔。

研究者采用4种不同标准来识别进展至憩室炎的患者：无客观进展证据的病历诊断、有客观数据支持但无影像学证据支持的诊断、有影像学证据支持的诊断，以及有外科样本支持的诊断。

在2,222人中，95人(4.3%)符合上述4种标准之一而被判断为进展至憩室炎，23人(1%)的憩室炎诊断是根据最严格标准(影像学证据或外科学证据)做出的。

分析结果显示，从憩室病进展至憩室炎的实际发生率为6例/1,000人·年。如果使用更严格的憩室病定义，则进展率更低，约为1.5例/1,000人-年。

分析还显示，憩室病患者进展至憩室炎的风险随年龄增加而明显降低，从首次查出憩室病起，每增加10岁，进展至憩室炎的风险就平均降低24%。进展至憩室炎的最高累计风险见于40岁时首次查出憩室病的患者，其次为50岁时首次查出憩室病的患者，以此类推，最低的风险见于70岁时首次查出憩室病的患者。

研究者怀疑，与年龄相关的进展风险模式可能缘于与结肠镜憩室病征象相关的偏倚，但在校正结肠镜征象后，仍发现较年轻的年龄是较快进展的显著独立危险因素。研究者表示，未来研究应注重探讨年龄如何及为何会影响进展风险。

爱思唯尔  版权所有


 

BY MITCHEL L. ZOLER
Elsevier Global Medical News
Breaking News

SAN DIEGO (EGMN)–A new study has found that people with diverticulosis actually have a low risk of progression to diverticulitis – far lower than the rates of 10%-25% commonly cited in the medical literature.

The actual rate seems to be at most six cases of progression from diverticulosis to diverticulitis for each 1,000 person years of follow-up. And if a stricter definition of diverticulitis is used, the rate for progression is even lower, 1.5 episodes for every 1,000 person-years, Dr. Kamyar Shahedi said at the meeting.

The newly derived rate came from a careful review of more than 2,000 people who were identified with diverticulosis in the U.S. Veterans Affairs Greater Los Angeles Healthcare System and followed for as long as 16 years.

The analysis also showed that the risk for developing diverticulitis subsequent to diagnosis of diverticulosis fell markedly with age, dropping by an average of 24% for each added decade of life from the time diverticulosis was first identified, said Dr. Shahedi, a gastroenterologist at the University of California, Los Angeles.

The highest cumulative hazard that people in the study faced for developing diverticulitis was if their diverticulosis was identified when they were in their 40s. The next highest rate of progression occurred among people first identified with diverticulosis in their 50s, and so on, with the lowest risk faced by people first found to have diverticulosis in their 70s.

Dr. Shahedi and his associates suspected that the age-related dimension to the risk for progression may have stemmed from a bias linked to the indication for the colonoscopy that found the diverticulosis, but after adjustment for the colonoscopy indication, younger age remained a significant, independent risk factor for more rapid progression. “Future research should try to explain how and why age affects risk,” he said.

Diverticulosis is the most common finding during colonoscopy. Results from a recent review of U.S. adults who underwent colonoscopy during 2001-2005 showed that the procedures identified about 45% with diverticulosis (Gastroenterology 2009;136:741-54).

Citations for a 10%-25% rate of progression of diverticulosis to diverticulitis appear widely in the literature, such as in 1999 diverticulitis guidelines published by the American College of Gastroenterology (Am. J. Gastroenterol. 1999;94:3110-21).

But in the 1999 ACG guidelines, the citation for the 10%-25% rate is a 1975 textbook, and when Dr. Shahedi checked the book he found that the original data behind this rate came out in the 1930s, 1940s, and 1950s. “Few recent studies” have calculated a more contemporary progression rate, and the studies that have been done were small, Dr. Shahedi said.

His study involved a manual chart review of all people in the VA Greater Los Angeles Health Care system identified with diverticulosis during 1996-2011. This system includes 14 community clinics and 1 inpatient medical center and serves about 3 million people.

The manual review excluded people with a prior diagnosis of diverticulosis, and identified 2,222 newly diagnosed cases. The records for these incident diverticulosis cases then underwent further careful review to flag the people who subsequently developed diverticulitis.

The researchers used four different criteria for identifying progression to diverticulitis: a chart diagnosis that included no objective evidence of progression, a diagnosis supported by objective data but without radiographic documentation, a diagnosis supported by imaging, and a diagnosis supported by a surgical specimen.

The review identified 95 of the 2,222 people (4.3%) who progressed to diverticulitis by any of these four criteria, and 23 people (1% of the 2,222) among these 95 whose progression to diverticulitis included documentation by at least one of the two strictest criteria, either radiographic or surgical evidence. The median time to progression to diverticulitis documented by any of the four criteria was 7.1 years.

The 2,222 people with diverticulosis were all veterans, their average age was 67 years, about 98% were men, and their average body mass index was 28.5 kg/m2. About 40% of the group was white, 10% African American, 8% Hispanic, and the rest were of other ethnic groups. Dr. Shahedi noted that the study was limited by examining a VA population that largely included men, it was a retrospective study, and all the people included came from a single health care system.

Dr. Shahedi said that he had no disclosures.

Findings Reassuring for Diverticulosis Patients

When we diagnose patients with diverticulosis by colonoscopy, they want to know the risk of its progress to the clinically important disease, diverticulitis, Dr. Philip S. Schoenfeld said in an interview. Prior data suggested that the risk was as high as 25%, which can be pretty scary, especially given how many people are identified with diverticulosis, said Dr. Schoenfeld, a gastroenterologist at the University of Michigan, and chief of gastroenterology at the VA Medical Center, both in Ann Arbor.

The new data reported by Dr. Shahedi show that the rate of progression is much lower. In fact, the rate is so low that if patients are first identified with diverticulosis in their 50s or 60s, it appears that the risk of progression to diverticulitis during the rest of their lives is very small, he said. Those first identified with diverticulosis in their 30s faces a much greater likelihood of eventually developing diverticulitis.

These new data are very helpful because they suggest that the risk is much lower than that usually quoted in the past, said Dr. Schoenfeld. There are certain limitations to these new data, which Dr. Shahedi acknowledged, but I believe these numbers more truly reflect what really happens. The methodology they used was much better than what was previously available, he said.

Dr. Philip S. Schoenfeld disclosed that he has been a consultant to Salix and Ironwood.