根據(jù)對一個美國大型回顧性索賠數(shù)據(jù)庫資料的分析，慢性便秘可能使患者更易發(fā)生結直腸癌和良性腫瘤。

　　澳大利亞新南威爾士州紐卡斯爾大學的Nicholas Talley博士報告，該研究納入1999年1月~2011年9月期間至少2次被診斷為慢性便秘(間隔60~365天)的年齡≥18歲的成年患者。排除腸易激綜合征或腹瀉患者，以及在首次診斷為便秘后至少12個月未繼續(xù)參與健康計劃的患者。對照受試者為觀察期內(nèi)從未被診斷為便秘且從未接受處方瀉藥治療者，基于出生年份、性別和居住地區(qū)與病例進行匹配，病例與對照人數(shù)比例為1:3。慢性便秘患者和對照者的平均年齡為61.9歲，其中1/3為男性。平均觀察期接近4年。

　　結果顯示，在這項研究中，慢性便秘患者的結直腸癌患病率為2.7%，對照者為1.7%；慢性便秘患者的良性腫瘤患病率為24.8%，對照者為11.9%。28,854例慢性便秘成年患者發(fā)生結直腸癌的風險為86,562例無慢性便秘對照者的1.78倍，并且慢性便秘患者發(fā)生良性腫瘤的風險為對照者的2.7倍。經(jīng)校正潛在混淆因素，包括年齡、性別、惡性疾病家族史和其他非胃腸道疾病后，慢性便秘患者的結直腸癌和良性腫瘤風險仍保持增高。盡管上述結果未能證實慢性便秘與結直腸癌或良性腫瘤之間存在因果關系，但提示具有很強的相關性。

　　研究者總結認為，臨床醫(yī)生應注意慢性便秘與結直腸癌、良性腫瘤之間的潛在關系，并對患者進行相應的監(jiān)測和治療。

　　Chronic constipation may predispose affected patients to developing colorectal cancer and benign neoplasms, according to an analysis of data from a large retrospective U.S. claims database.

　　The risk of developing colorectal cancer was 1.78 times higher among 28,854 adults with chronic constipation than among 86,562 controls without chronic constipation, and the risk of developing benign neoplasms was 2.7 times higher in those with chronic constipation, Dr. Nicholas Talley reported in a poster at the annual meeting of the American College of Gastroenterology.

　　The risk of colorectal cancer and benign neoplasms among those with chronic constipation remained "consistently high" after researchers controlled for potential confounding factors, including age, gender, family history of malignancies, and other nongastrointestinal morbidities, said Dr. Talley of the University of Newcastle, Callaghan, New South Wales, Australia.

　　Patients included adults aged older than 18 years who received at least two diagnoses of chronic constipation 60-365 days apart between January 1999 and September 2011. Those with irritable bowel syndrome or diarrhea were excluded, as were those who did not remain enrolled in their health plans for at least 12 months from the date of their first eligible diagnosis of constipation.

　　The investigators matched control subjects, who had never been diagnosed with constipation and never had a presc**tion filled for a laxative during the observation period, with case patients in a 1:3 ratio based on year of birth, sex, and region of residence.

　　Patients and controls had a mean age of 61.9 years, and one-third were men. The mean observation period was nearly 4 years.

　　The prevalence of colorectal cancer in this study was 2.7% in the patients and 1.7% in the controls; the prevalence of benign neoplasms was 24.8% in the patients and 11.9% in the controls, Dr. Talley said.

　　Although the findings do not prove a causal link between chronic constipation and colorectal cancer or benign neoplasms, they do suggest a strong association, he said in a press statement.

　　"The postulated causal link is that longer transit times increase the duration of contact between the colonic mucosa and concentrated carcinogens such as bile acids in the lumen," he said.

　　This association deserves further investigation to more thoroughly explore and to better understand possible causal elements, he added.

　　This is particularly important because prospective cohort studies have failed to identify a similar association to that seen in this retrospective review, suggesting that those findings are affected by recall bias, he said.

　　While further study is needed, practitioners should be aware of the potential relationship between chronic constipation and development of colorectal cancer and benign neoplasms, and should monitor and treat patients accordingly, he concluded.