Constantinos Simillis

The Risk of Oral Contraceptives in the Etiology of Inflammatory Bowel Disease: A Meta-Analysis

OBJECTIVES:Several environmental and genetic factors have been implicated to date in the development of Crohns disease (CD) and ulcerative colitis (UC). The aim of this study was to provide a quantification of the risk of oral contraceptive pill (OCP) use in the etiology of inflammatory bowel disease.METHODS:A literature search was performed to identify comparative studies reporting on the association of oral contraceptive use in the etiology of UC and CD between 1983 and 2007. A random-effect meta-analysis was used to compare the incidence of UC or CD between the patients exposed to the OCP and nonexposed patients. The results were adjusted for smoking.RESULTS:A total of 75,815 patients were reported on by 14 studies, with 36,797 exposed to OCP and 39,018 nonexposed women. The pooled relative risk (RR) for CD for women currently taking the OCP was 1.51 (95% confidence interval [CI] 1.17–1.96, P = 0.002), and 1.46 (95% CI 1.26–1.70, P < 0.001), adjusted for smoking. The RR for UC in women currently taking the OCP was 1.53 (95% CI 1.21–1.94, P = 0.001), and 1.28 (95% CI 1.06–1.54, P = 0.011), adjusted for smoking. The RR for CD increased with the length of exposure to OCP. Moreover, although the RR did not reduce once the OCP was stopped, it was no longer significant once the OCP was stopped (CI contains 1), both for CD and for UC.CONCLUSIONS:This study provides evidence of an association between the use of oral contraceptive agents and development of IBD, in particular CD. The study also suggests that the risk for patients who stop using the OCP reverts to that of the nonexposed population.

Diagnostic precision of anti-Saccharomyces cerevisiae antibodies and perinuclear antineutrophil cytoplasmic antibodies in inflammatory bowel disease

AIMS:The aim of this study was to assess the diagnostic precision of antiSaccharomyces cerevisiae (ASCA) and perinuclear antineutrophil cytoplasmic antibodies (pANCA) in inflammatory bowel disease (IBD) and evaluate their discriminative ability between ulcerative colitis (UC) and Crohns disease (CD).METHODS:Meta-analysis of studies reporting on ASCA and pANCA in IBD was performed. Sensitivity, specificity, and likelihood ratios (LR+, LR–) were calculated for different test combinations for CD, UC, and for IBD compared with controls. Meta-regression was used to analyze the effect of age, DNAse, colonic CD, and assay type.RESULTS:Sixty studies comprising 3,841 UC and 4,019 CD patients were included. The ASCA+ with pANCA– test offered the best sensitivity for CD (54.6%) with 92.8% specificity and an area under the ROC (receiver operating characteristic) curve (AUC) of 0.85 (LR+ = 6.5, LR– = 0.5). Sensitivity and specificity of pANCA+ tests for UC were 55.3% and 88.5%, respectively (AUC of 0.82; LR+ = 4.5, LR– = 0.5). Sensitivity and specificity were improved to 70.3% and 93.4% in a pediatric subgroup when combined with an ASCA– test. Meta-regression analysis showed decreased diagnostic precision of ASCA for isolated colonic CD (RDOR = 0.3).CONCLUSIONS:ASCA and pANCA testing are specific but not sensitive for CD and UC. It may be particularly useful for differentiating between CD and UC in the pediatric population.

A meta-analysis comparing conservative treatment versus acute appendectomy for complicated appendicitis (abscess or phlegmon).

BACKGROUND No standardized approach is available for the management of complicated appendicitis defined as appendiceal abscess and phlegmon. This study used meta-analytic techniques to compare conservative treatment versus acute appendectomy. METHODS Comparative studies were identified by a literature search. The end points evaluated were overall complications, need for reoperation, duration of hospital stay, and duration of intravenous antibiotics. Heterogeneity was assessed and a sensitivity analysis was performed to account for bias in patient selection. RESULTS Seventeen studies (16 nonrandomized retrospective and 1 nonrandomized prospective) reported on 1,572 patients: 847 patients received conservative treatment and 725 had acute appendectomy. Conservative treatment was associated with significantly less overall complications, wound infections, abdominal/pelvic abscesses, ileus/bowel obstructions, and reoperations. No significant difference was found in the duration of first hospitalization, the overall duration of hospital stay, and the duration of intravenous antibiotics. Overall complications remained significantly less in the conservative treatment group during sensitivity analysis of studies including only pediatric patients, high-quality studies, more recent studies, and studies with a larger group of patients. CONCLUSION The conservative management of complicated appendicitis is associated with a decrease in complication and reoperation rate compared with acute appendectomy, and it has a similar duration of hospital stay. Because of significant heterogeneity between studies, additional studies should be undertaken to confirm these findings.

A meta-analysis comparing conventional end-to-end anastomosis vs. other anastomotic configurations after resection in Crohn's disease

PurposeThis study compared outcomes between end-to-end anastomosis and other anastomotic configurations after intestinal resection for patients with Crohn’s disease by using meta-analytical techniques.MethodsComparative studies published between 1992 and 2005 of end-to-end anastomosis vs. other anastomotic configurations were included. Using a random effects model, end points evaluated were short-term complications and perianastomotic recurrence of Crohn’s disease. Heterogeneity was assessed and sensitivity analysis was performed to account for bias in patient selection.ResultsEight studies (2 prospective, randomized, controlled trials; 1 nonrandomized, prospective; 5 nonrandomized, retrospective studies) reported on 661 patients who underwent 712 anastomoses, of which 383 (53.8 percent) were sutured end-to-end anastomosis and 329 (46.2 percent) were other anastomotic configurations (259 stapled side-to-side, 59 end-to-side or side-to-end, 11 stapled circular end-to-end). Anastomotic leak rate was significantly reduced in the other anastomotic configurations group (odds ratio (OR), 4.37; P = 0.02) and remained significantly lower in studies comparing only side-to-side anastomosis vs. end-to-end anastomosis (OR, 4.37; P = 0.02) and studies including only ileocolonic anastomosis (OR, 3.8; P = 0.05). Overall postoperative complications (OR, 2.64; P < 0.001), complications other than anastomotic leak (OR, 1.89; P = 0.04), and postoperative hospital stay (weighted mean difference, 2.81; P = 0.007) were significantly reduced in the side-to-side anastomosis group when considering studies comparing only side-to-side anastomosis vs. end-to-end anastomosis. There was no significant difference between the groups in perianastomotic recurrence and reoperation needed because of perianastomotic recurrence.ConclusionsEnd-to-end anastomosis after resection for Crohn’s disease may be associated with increased anastomotic leak rates. Side-to-side anastomosis may lead to fewer anastomotic leaks and overall postoperative complications, a shorter hospital stay, and a perianastomotic recurrence rate comparable to end-to-end anastomosis. Further randomized, controlled trials should be performed for confirmation.

A meta-analysis comparing incidence of recurrence and indication for reoperation after surgery for perforating versus nonperforating Crohn's disease.

OBJECTIVE:This study used meta-analytical techniques to compare the incidence of recurrence and the indication for reoperation in patients with Crohns disease (CD) who underwent their first operation, due to perforating disease versus patients who underwent their first operation due to nonperforating disease.METHODS:Comparative studies published between 1988 and 2005 of perforating versus nonperforating CD were included. Using a random effects model, end points evaluated were recurrence of CD given as reoperation, and the indication for reoperation, i.e., perforating or nonperforating. Heterogeneity (HG) was assessed and a sensitivity analysis was performed to account for bias in patient selection.RESULTS:Thirteen studies (12 nonrandomized retrospective, 1 nonrandomized prospective) reported on 3,044 patients, of which 1,337 (43.9%) had perforating indications (P group) and 1,707 (56.1%) had nonperforating indications (NP group) for surgery. The recurrence was found to be significantly higher in the P group compared to the NP group (HR 1.50, P = 0.002), with significant HG among studies (P < 0.001). The recurrence remained significantly higher in the P group compared with the NP group during sensitivity analysis of high-quality studies (HR 1.47, P = 0.005) and more recent studies (HR 1.51, P = 0.05), but still demonstrating significant HG (P = 0.08 and P < 0.001, respectively). At reoperation, concordance was found in the disease type of those patients re-presenting with perforating disease (OR 5.93, P < 0.001, without significant HG among studies P = 0.15) and those with nonperforating disease (OR 5.73, P < 0.001, with significant HG among studies P < 0.001). Concordance in disease type remained when considering only high-quality studies (P: OR 7.48, P < 0.001; NP: OR 7.48, P < 0.001) and more recent studies (P: OR 5.95, P < 0.001; NP: OR 5.95, P < 0.001), both not associated with HG among studies (P = 0.47 and P = 0.60, respectively).CONCLUSIONS:The indication for reoperation in CD tends to be the same as the primary operation, i.e., perforating disease tends to re-present as perforating disease, and nonperforating as nonperforating. Also, perforating CD appears to be associated with a higher recurrence rate compared with nonperforating CD. However, because of significant HG among studies, further studies should be undertaken to confirm this finding.

Systematic review and network meta-analysis comparing clinical outcomes and effectiveness of surgical treatments for haemorrhoids

The aim was to compare the clinical outcomes and effectiveness of surgical treatments for haemorrhoids.

A systematic review of transanal total mesorectal excision: is this the future of rectal cancer surgery?

The surgical technique used for transanal total mesorectal excision (TaTME) was reviewed including the oncological quality of resection and the peri‐operative outcome.

Meta-analysis of the role of granulomas in the recurrence of Crohn disease.

PURPOSE: This study used meta-analytical techniques to compare the recurrence of granulomatous vs nongranulomatous Crohn disease. METHODS: Comparative studies published between 1954 and 2007 of granulomatous vs nongranulomatous Crohn disease were included. Using a random effects model, end points evaluated were the number of recurrences and reoperations, and the time to recurrence and reoperation, of granulomatous vs nongranulomatous Crohn disease. Heterogeneity was assessed and sensitivity analysis was performed to account for bias in patient selection. RESULTS: Twenty-one studies (14 nonrandomized retrospective, 7 nonrandomized prospective) reported on 2236 patients with Crohn disease, of whom 1050 (47.0%) had granulomas (granulomatous group) and 1186 (53.0%) had no granulomas (nongranulomatous group). The number of recurrences and reoperations was found to be significantly higher in the granulomatous group compared to the nongranulomatous group (odds ratio 1.37, P = .04; odds ratio 2.38, P < .001; respectively), with significant heterogeneity between studies (P = .06; P < .001; respectively). The time to recurrence and reoperation was significantly shorter in the granulomatous group compared with the nongranulomatous group (hazard ratio 1.63, P = .001; hazard ratio 1.62, P = .002; respectively), with no significant heterogeneity between studies. The number of recurrences and reoperations remained significantly higher in the granulomatous group compared to the nongranulomatous group during sensitivity analysis of higher-quality studies, more recent studies, and studies with a larger group of patients. CONCLUSIONS: Granulomatous Crohn disease appears to be associated with a higher number of recurrences and reoperations and a shorter time to recurrence and reoperation compared to nongranulomatous Crohn disease. Because of significant heterogeneity between studies, further studies should be undertaken to confirm these findings.

A Systematic Review to Assess Resection Margin Status After Abdominoperineal Excision and Pelvic Exenteration for Rectal Cancer.

Objective: The aim of this study was to assess resection margin status and its impact on survival after abdominoperineal excision and pelvic exenteration for primary or recurrent rectal cancer. Summary of Background Data: Resection margin is important to guide therapy and to evaluate patient prognosis. Methods: A meta-analysis was performed to assess the impact of resection margin status on survival, and a regression analysis to analyze positive resection margin rates reported in the literature. Results: The analysis included 111 studies reporting on 19,607 participants after abdominoperineal excision, and 30 studies reporting on 1326 participants after pelvic exenteration. The positive resection margin rates for abdominoperineal excision were 14.7% and 24.0% for pelvic exenteration. The overall survival and disease-free survival rates were significantly worse for patients with positive compared with negative resection margins after abdominoperineal excision [hazard ratio (HR) 2.64, P < 0.01; HR 3.70, P < 0.01, respectively] and after pelvic exenteration (HR 2.23, P < 0.01; HR 2.93, P < 0.01, respectively). For patients undergoing abdominoperineal excision with positive resection margins, the reported tumor sites were 57% anterior, 15% posterior, 10% left or right lateral, 8% circumferential, 10% unspecified. A significant decrease in positive resection margin rates was identified over time for abdominoperineal excision. Although positive resection margin rates did not significantly change with the size of the study, some small size studies reported higher than expected positive resection margin rates. Conclusions: Resection margin status influences survival and a multidisciplinary approach in experienced centers may result in reduced positive resection margins. For advanced anterior rectal cancer, posterior pelvic exenteration instead of abdominoperineal excision may improve resection margins.

A meta-analysis comparing the risk of metastases in patients with rectal cancer and MRI-detected extramural vascular invasion (mrEMVI) vs mrEMVI-negative cases

Background:Pathological extramural vascular invasion (EMVI) is an independent prognostic factor in rectal cancer, but can also be identified on MRI-detected extramural vascular invasion (mrEMVI). We perform a meta-analysis to determine the risk of metastatic disease at presentation and after surgery in mrEMVI-positive patients compared with negative tumours.Methods:Electronic databases were searched from January 1980 to March 2016. Conventional meta-analytical techniques were used to provide a summative outcome. Quality assessment of the studies was performed.Results:Six articles reported on mrEMVI in 1262 patients. There were 403 patients in the mrEMVI-positive group and 859 patients in the mrEMVI-negative group. The combined prevalence of mrEMVI-positive tumours was 0.346(range=0.198–0.574). Patients with mrEMVI-positive tumours presented more frequently with metastases compared to mrEMVI-negative tumours (fixed effects model: odds ratio (OR)=5.68, 95% confidence interval (CI) (3.75, 8.61), z=8.21, df=2, P<0.001). Patients who were mrEMVI-positive developed metastases more frequently during follow-up (random effects model: OR=3.91, 95% CI (2.61, 5.86), z=6.63, df=5, P<0.001).Conclusions:MRI-detected extramural vascular invasion is prevalent in one-third of patients with rectal cancer. MRI-detected extramural vascular invasion is a poor prognostic factor as evidenced by the five-fold increased rate of synchronous metastases, and almost four-fold ongoing risk of developing metastases in follow-up after surgery.