Systematic review and meta-regressions: management of eosinophilic esophagitis requires histologic assessment.

Treatment endpoints in eosinophilic esophagitis (EoE) are response of eosinophilic inflammation and of symptoms. Steroids and diet therapy are effective in inducing histologic response in EoE, but there may be poor correlation between histologic and symptomatic response. Despite this, we find that in clinical practice symptoms are commonly used to guide management without assessing histologic response. We hypothesized that symptom response alone is not reliable in assessing response to therapy and is confounded by endoscopic dilation. We conducted a systematic review and meta-regressions to estimate the association of histologic and symptomatic response, stratified by whether concurrent dilation was permitted. We performed a systematic search of PubMed, EMBASE, and Web of Science for studies describing both histologic and symptomatic responses to dilation, steroid, and diet therapies. We abstracted the proportion of histologic response and symptom response. Studies were stratified by whether dilation was permitted. We performed meta-regressions of the association between the proportions with histologic and symptomatic response, stratified by whether dilation was permitted. We identified 1359 articles, of which 62 articles were assessed for eligibility, and 23 were included providing data on 1202 patients with EoE. Unstratified meta-regression of histologic versus symptomatic response showed moderate association and large heterogeneity (inconsistency index [I2] = 89%). In adult studies in which dilation was allowed, there was weak association between symptomatic and histologic response (ß1 = 0.21), minimal symptomatic response of 67% and the heterogeneity persisted, I2 = 77%. In studies that prohibited dilation, maximal symptomatic response was 72% and was moderately associated with histologic response (ß1 = 0.39) with less heterogeneity, I2 = 59%. Studies of EoE that permit dilation obscure the relation between histologic and symptomatic response and have a high floor effect for symptomatic response. Studies that prohibit dilation demonstrate moderate association between histologic and symptomatic response, but have a ceiling effect for symptomatic response. Our results demonstrate that success of dietary or medical management for EoE cannot be judged by symptoms alone, and require histologic assessment, particularly if dilation has been performed.

Predicting corticosteroid-free endoscopic remission with vedolizumab in ulcerative colitis.

BACKGROUND: Vedolizumab is an effective therapy for ulcerative colitis (UC), but costly and slow to work. New clinical responses occur after 30 weeks of therapy. AIMS: To enable physicians, patients, and insurers to predict whether a patient with UC will respond to vedolizumab at an early time point after starting therapy. METHODS: The clinical study data request website provided the phase 3 clinical trial data for vedolizumab. Random forest models were trained on 70% and tested on 30% of the data to predict corticosteroid-free endoscopic remission at week 52. Models were constructed using baseline data, or data through week 6 of vedolizumab therapy from 491 subjects. RESULTS: The AuROC for prediction of corticosteroid-free endoscopic remission at week 52 using baseline data was only 0.62 (95% CI: 0.53-0.72), but was 0.73 (95% CI: 0.65-0.82) when using data through week 6. A total of 47% of subjects were predicted to be remitters, and 59% of these subjects achieved corticosteroid-free endoscopic remission, in contrast to 21% of the predicted non-remitters. A week 6 prediction using FCP ≤234 µg/g was nearly as accurate. CONCLUSIONS: A machine learning algorithm using laboratory data through week 6 of vedolizumab therapy was able to accurately identify which UC patients would achieve corticosteroid-free endoscopic remission on vedolizumab at week 52. Application of this algorithm could have significant implications for clinical decisions on whom to continue on this costly medication when the benefits of the vedolizumab are not clinically apparent in the first 6 weeks of therapy.

Systematic review with network meta-analysis: the efficacy of anti-TNF agents for the treatment of Crohn's disease.

BACKGROUND: Anti-tumour necrosis factor-alpha agents (anti-TNF) are effective therapies for the treatment of Crohn's disease (CD), but their comparative efficacy is unknown. AIM: To perform a network meta-analysis comparing the efficacy of anti-TNF therapies in CD. METHODS: After screening 506 studies, reviewers extracted information on 10 studies. Traditional meta-analysis (TMA) was used to compare each anti-TNF agent to placebo. Bayesian network meta-analysis (NMA) was performed to compare the effects of anti-TNF agents to placebo. In addition, sample sizes for comparative efficacy trials were calculated. RESULTS: Compared to placebo, TMA revealed that anti-TNF agents result in a higher likelihood of induction of remission and response (RR: 1.66, 95% CI: 1.17-2.36 and RR: 1.43, 95% CI: 1.17-1.73, respectively) as well as maintenance of remission and response (RR: 1.78, 95% CI: 1.51-2.09 and RR: 1.68, 95% CI: 1.46-1.93, respectively). NMA found nonsignificant trends between infliximab and adalimumab or certolizumab pegol. Among subcutaneous therapies, NMA demonstrated superiority of adalimumab to certolizumab pegol for induction of remission (RR: 2.93, 95% CrI: 1.21-7.75). Sample size calculations suggest that adequately powered head-to-head comparative efficacy trials would require greater than 3000 patients. CONCLUSIONS: All anti-TNF agents are effective for induction and maintenance of response and remission in the treatment of CD. Although adalimumab is superior to certolizumab pegol for induction of remission, there is no evidence of clinical superiority among anti-TNF agents. Head-to-head trials among the anti-TNF agents are impractical in terms of size and cost.

Systematic review with network meta-analysis: the efficacy of anti-tumour necrosis factor-alpha agents for the treatment of ulcerative colitis.

BACKGROUND: Antibodies against tumour necrosis factor-alpha (anti-TNF) are effective therapies in the treatment of ulcerative colitis (UC), but their comparative efficacy is unknown. AIM: To perform a network meta-analysis comparing the efficacy of anti-TNF agents in UC. METHODS: After screening 506 studies, reviewers extracted information on seven studies. Traditional meta-analysis (TMA) was used to compare each anti-TNF agent to placebo. Bayesian network meta-analysis (NMA) was performed to compare the effects of anti-TNF agents to placebo. In addition, sample sizes for comparative efficacy trials were calculated. RESULTS: Compared to placebo, TMA revealed that anti-TNF agents result in a higher likelihood of induction of remission and response (RR: 2.45, 95% CI: 1.72-3.47 and RR: 1.65, 95% CI: 1.37-1.99 respectively) as well as maintenance of remission and response (RR: 2.00, 95% CI: 1.52-2.62 and RR: 1.76, 95% CI: 1.46-2.14 respectively). Individually, infliximab, adalimumab and goliumumab resulted in a higher likelihood of induction and maintenance for both remission and response. NMA found nonsignificant trends in comparisons of the individual agents. The required sample sizes for direct head-to-head trials between infliximab and adalimumab for induction and maintenance are 174 and 204 subjects respectively. CONCLUSIONS: This study demonstrates that, compared to placebo, infliximab, adalimumab and golimumab are all effective for the induction and maintenance of remission in ulcerative colitis. However, network meta-analysis demonstrates that no single agent is clinically superior to the others and therefore, other factors such as cost, safety, route of administration and patient preference should dictate our choice of anti-TNF agents. A randomised comparative efficacy trial between infliximab and adalimumab in UC is of practical size and should be performed.

Meta-analysis: re-treatment of genotype I hepatitis C nonresponders and relapsers after failing interferon and ribavirin combination therapy.

BACKGROUND: The efficacy of re-treating genotype I hepatitis C virus (HCV) patients who failed combination therapy with interferon/pegylated interferon (PEG-IFN) and ribavirin remains unclear. AIMS: To quantify sustained virological response (SVR) rates with different re-treatment regimens through meta-analysis of randomized controlled trials (RCTs). METHODS: Randomized controlled trials of genotype I HCV treatment failure patients that compared currently available re-treatment regimens were selected. Two investigators independently extracted data on patient population, methods and results. The pooled relative risk of SVR for treatment regimens was computed using a random effects model. RESULTS: Eighteen RCTs were included. In nonresponders to standard interferon/ribavirin, re-treatment with high-dose PEG-IFN combination therapy improved SVR compared with standard PEG-IFN combination therapy (RR=1.49; 95% CI: 1.09-2.04), but SVR rates did not exceed 18% in most studies. In relapsers to standard interferon/ribavirin, re-treatment with high-dose PEG-IFN or prolonged CIFN improved SVR (RR=1.57; 95% CI: 1.16-2.14) and achieved SVR rates of 43-69%. CONCLUSIONS: In genotype I HCV treatment failure patients who received combination therapy, re-treatment with high-dose PEG-IFN combination therapy is superior to re-treatment with standard combination therapy, although SVR rates are variable for nonresponders (≤18%) and relapsers (43-69%). Re-treatment may be appropriate for select patients, especially relapsers and individuals with bridging fibrosis or compensated cirrhosis.

Systematic review: efficacy and safety of pancreatic enzyme supplements for exocrine pancreatic insufficiency.

BACKGROUND: Pancreatic enzyme supplements are standard therapy for fat malabsorption in patients with exocrine pancreatic insufficiency. The FDA determined that published data are insufficient to support the efficacy and safety of these agents. AIM: To determine if pancreatic enzyme supplements are: (i) superior to placebo for treating fat malabsorption and (ii) superior to other supplements based on randomized cross-over trials. METHODS: A computer-assisted search of MEDLINE and EMBASE was performed to identify relevant studies. Data extraction on study design, improvement in coefficient of fat absorption, diarrhoea and adverse events using prespecified forms. RESULTS: A total of 12 manuscripts met inclusion criteria. Most studies (10/12) compared pancreatic enzyme supplements that used different delivery systems, while using similar quantities of enzymes. These studies found no consistent difference in fat malabsorption or gastrointestinal symptoms between different active treatments. Two small placebo-controlled trials (n = 65 patients) demonstrate that pancreatic enzyme supplements are superior to placebo for fat absorption. Data are inadequate to determine if pancreatic enzyme supplements lead to weight gain or improvement in diarrhoea. CONCLUSIONS: Based on data from randomized cross-over trials, pancreatic enzyme supplements appear to improve fat malabsorption. No specific branded product or specific delivery system is superior for treatment of fat malabsorption in patients with exocrine pancreatic insufficiency.

Meta-analysis: surveillance with ultrasound for early-stage hepatocellular carcinoma in patients with cirrhosis.

BACKGROUND: A majority of studies investigating the accuracy of ultrasound for detecting hepatocellular carcinoma (HCC) do not reflect how this test is used for surveillance vs. diagnosis. AIM: To determine the performance characteristics of surveillance with ultrasound for the detection of HCC, particularly early HCC as defined by the Milan criteria. METHODS: A systematic literature review using the MEDLINE and SCOPUS databases yielded six studies that evaluated the accuracy of ultrasound for HCC at any stage and 13 studies that were specific to early HCC. RESULTS: Surveillance ultrasound detected the majority of tumours before they presented clinically, with a pooled sensitivity of 94%. However, ultrasound was less effective for detecting early HCC with a sensitivity of 63%. Alpha-fetoprotein provided no additional benefit to ultrasound. Meta-regression analysis demonstrated a significantly higher sensitivity for early HCC with ultrasound every 6 months than with annual surveillance. Current studies have limitations such as verification bias and are of suboptimal quality. CONCLUSIONS: Surveillance with ultrasound demonstrates limited sensitivity for early HCC, although this may be improved by testing at 6-month intervals. Currently available evidence evaluating surveillance ultrasound has significant limitations and future studies are necessary to determine optimal surveillance methods for early HCC.

Systematic review: pancreatic enzyme treatment of malabsorption associated with chronic pancreatitis.

BACKGROUND: Pancreatic enzyme supplementation is standard treatment for malabsorption caused by chronic pancreatitis. The FDA recently required all manufacturers to submit New Drug Applications to continue to market these agents because published data demonstrated variation in formulation, bioavailability and shelf-life while providing limited data about efficacy and safety. AIM: To review systematically the design and results of randomized, parallel-design trials of pancreatic enzyme supplements in chronic pancreatitis patients with steatorrhea. METHODS: A computer-assisted search of MEDLINE and EMBASE was performed to identify relevant studies. Two authors performed duplicate data extraction on study design, improvement in coefficient of fat absorption (CFA), diarrhoea and adverse events using pre-specified forms. Agreement between investigators for data extraction was greater than 95%. RESULTS: Of 619 articles found through literature searching, 20 potentially relevant articles were identified and four manuscripts met inclusion criteria. No studies performed head-to-head comparisons of different supplements. Enzyme supplementation is more likely to improve CFA compared with placebo, but fat malabsorption remained abnormal. Important differences in patient population, study endpoint, study design, pancreatic enzyme dosage and measurement of CFA were present across trials, which precluded comparison of different agents. CONCLUSIONS: Enzyme supplementation improves CFA compared to placebo, but may not abolish steatorrhoea.

A meta-analysis of rectal NSAIDs in the prevention of post-ERCP pancreatitis.

BACKGROUND: Several pharmacological agents for the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) have been studied. Clinical trials evaluating the protective effect of non-steroidal anti-inflammatory drugs (NSAIDs) have yielded inconclusive results. AIM: To perform a meta-analysis of studies evaluating the effect of prophylactic rectal NSAIDs on PEP. METHODS: By searching Medline, Embase, meeting abstracts and bibliographies, two independent reviewers systematically identified prospective randomised controlled trials (RCTs) examining the effect of rectally administered prophylactic NSAIDs on the incidence of PEP pancreatitis. A meta-analysis of these clinical trials was performed. RESULTS: Four RCTs, enrolling a total of 912 patients, have been published. Meta-analysis of these studies demonstrates a pooled relative risk for PEP after prophylactic administration of NSAIDs of 0.36 (95% CI 0.22 to 0.60); patients who received NSAIDs in the periprocedural period were 64% less likely to develop pancreatitis and 90% less likely to develop moderate to severe pancreatitis. The pooled number needed to treat with NSAIDs to prevent one episode of pancreatitis is 15 patients. No adverse events attributable to the use of NSAIDs were reported in any of the clinical trials. CONCLUSION: In this meta-analysis, prophylactic NSAIDs were effective in preventing PEP. Widespread prophylactic administration of these agents may significantly reduce the incidence of PEP, resulting in major clinical and economic benefit. Given current scepticism regarding the efficacy of any prophylactic medication for ERCP, additional multicentre studies are needed for confirmation prior to widespread adoption of this strategy.

Threefold increased risk of infertility: a meta-analysis of infertility after ileal pouch anal anastomosis in ulcerative colitis.

BACKGROUND: Increased infertility in women has been reported after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis but reported infertility rates vary substantially. AIMS: (1) To perform a systematic review and meta-analysis of the relative risk of infertility post-IPAA compared with medical management; (2) to estimate the rate of infertility post-IPAA; and (3) to identify modifiable risk factors which contribute to infertility. METHODS: Medline, EMBASE, Current Contents, meeting abstracts, and bibliographies were searched independently by two investigators. The titles and abstracts of 189 potentially relevant studies were reviewed; eight met the criteria and all data were extracted independently. Consensus was achieved on each data point, and fixed effects meta-analyses, a funnel plot, and sensitivity analyses were performed. RESULTS: The initial meta-analysis of eight studies had significant heterogeneity (p = 0.004) due to one study with very high preoperative infertility (38%). When this study was omitted, the relative risk of infertility after IPAA was 3.17 (2.41-4.18), with non-significant heterogeneity. The weighted average infertility rate in medically treated ulcerative colitis was 15% for all seven studies, and the weighted average infertility rate was 48% after IPAA (50% if all eight studies are included). We were unable to identify any procedural factors that consistently affected the risk of infertility. CONCLUSIONS: IPAA increases the risk of infertility in women with ulcerative colitis by approximately threefold. Infertility, defined as achieving pregnancy in 12 months of attempting conception, increased from 15% to 48% in women post-IPAA for ulcerative colitis. This provides a basis for counselling patients considering colectomy with IPAA. Further studies of modifiable risk factors are needed.