Suhal S. Mahid

Smoking and Inflammatory Bowel Disease: A Meta-analysis

OBJECTIVE To assess whether there is a true effect of smoking on the 2 most prevalent forms of inflammatory bowel disease (IBD): Crohn disease (CD) and ulcerative colitis (UC). METHODS For this meta-analysis, we searched multiple health care databases, including MEDLINE and EMBASE (January 1980 to January 2006), to examine the relationship between smoking and IBD. Keywords searched included smoking, Inflammatory bowel disease, Crohns disease, and ulcerative colitis. Data were abstracted using predefined inclusion and exclusion criteria. An odds ratio (OR) was recalculated for each study using the random-effects model, and a combined OR was calculated. RESULTS A total of 245 articles were obtained through an electronic search of health care databases. Thirteen studies examined the relationship between UC and smoking, whereas 9 examined the relationship between CD and smoking. We found evidence of an association between current smoking and CD (OR, 1.76; 95% confidence interval [CI], 1.40-2.22) and former smoking and UC (OR, 1.79; 95% CI, 1.37-2.34). Current smoking had a protective effect on the development of UC when compared with controls (OR, 0.58; 95% CI, 0.45-0.75). CONCLUSION This is the first meta-analysis, to our knowledge, to evaluate the relationship between smoking and IBD using accepted quality standards for meta-analysis reporting. Our meta-analyses confirm that smoking is an important environmental factor in IBD with differing effects in UC and CD. By using predefined inclusion criteria and testing for homogeneity, the current analysis provides an estimate of the effect of smoking on both these forms of IBD.

Meta‐analysis: antibiotic prophylaxis to prevent peristomal infection following percutaneous endoscopic gastrostomy

Despite numerous guidelines recommending prophylactic antibiotics prior to percutaneous endoscopic gastrostomy, their use remains controversial.

Active and passive smoking in childhood is related to the development of inflammatory bowel disease

Background: The highest prevalence of smoking in the United States is in Kentucky, where smoking typically begins in childhood. The state has many patients who suffer from inflammatory bowel diseases (IBD). The primary aim of this study was to assess whether exposure to active and/or passive tobacco smoke in childhood is related to the likelihood of developing IBD. Methods: Recruited into this prospective study were a total of 672 participants (253 patients with Crohns disease [CD], 177 patients with ulcerative colitis [UC], and 242 controls), all of whom were asked to complete the Behavioral Risk Factor Surveillance Survey modified by the addition of 4 questions on childhood passive smoke exposure. Results: Survey response rate was 84%. CD and UC patients were more likely than controls to begin smoking regularly by ages 10 and 15, respectively, suggesting that becoming a regular smoker at a younger age may be associated with a subsequent diagnosis of IBD. Smoking by age 10 was associated with an earlier age at diagnosis with UC, but not with CD. CD patients were more likely than controls to have prenatal smoke exposure (odds ratio [OR], 1.72; 95% confidence interval [CI], 1.1–2.71) and were more likely to have passive smoke exposure during childhood, with 1 or both parents or other household members being smokers (OR, 2.04; 95% CI, 1.28–3.31). Conclusions: Passive and active smoke exposure in childhood influences the development of IBD. A high incidence of this disease in a state with a high rate of cigarette smoking underscores the profound role of environmental factors in the etiology of these illnesses.

Antibiotic prophylaxis is not protective in severe acute pancreatitis: a systematic review and meta-analysis

BACKGROUND The use of prophylactic systemic antibiotics to prevent infection and reduce mortality in severe acute pancreatitis (SAP) remains a contentious issue. We assessed the clinical outcome of patients with SAP treated with prophylactic antibiotics compared with that of patients not treated with antibiotics. METHODS We performed a systematic search of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials, using PubMed, Google Scholar, and Ovid as search engines without language restriction until the end of May 2008. We also manually searched the references of original/review articles and evaluated symposia proceedings, poster presentations, and abstracts from major gastrointestinal and surgical meetings. Relative risks were calculated for individual trials and data were pooled using a fixed-effects model. Relative risk (RR) reduction, absolute risk reduction, and number needed to treat were calculated and are reported with 95% confidence intervals. RESULTS Results were subjected to sensitivity analysis to determine heterogeneity among studies. We pooled 502 patients from 8 studies. Patient age ranged from 43 to 59 years, and length of stay ranged from 18 to 95 days. There were 253 patients with SAP who received prophylactic antibiotics, and 249 patients were randomized to the placebo arm. Overall, there was no protective effect of antibiotic treatment with respect to mortality (RR, .76; 95% confidence interval [CI], .49-1.16). With respect to morbidity, antibiotic prophylaxis did not protect against infected necrosis (RR, .79; 95% CI, .56-1.11) or surgical intervention (RR, .88; 95% CI, .65-1.20). There was, however, an apparent benefit in regards to nonpancreatic infections (RR, .60; 95% CI, .44-.82), with a RR reduction of 40% (95% CI, 18%-56%), absolute risk reduction of 15% (95% CI, 6%-23%), and number needed to treat of 7 (95% CI, 4-17). CONCLUSIONS Antibiotic prophylaxis of SAP does not reduce mortality or protect against infected necrosis, or frequency of surgical intervention.

Frequency and surgical management of chronic complications related to pelvic radiation.

HYPOTHESIS Refractory complications from pelvic radiotherapy often require surgical treatment. Their management may be dictated by the primary tumor, radiation dose, and type and combination of radiation injuries, and may require transient diversion in most cases to guarantee good outcomes. DESIGN Retrospective 10-year cohort analysis compared with statewide epidemiologic data. PATIENTS During a 10-year period, 14 791 patients in Kentucky were treated with pelvic radiotherapy. Forty-eight were referred to a university colorectal surgical unit for evaluation of refractory radiotherapy complications that had failed conservative medical management. MAIN OUTCOME MEASURES Epidemiologic statewide data were compared with hospital data regarding the treatment and outcome of patients with refractory pelvic radiotherapy complications. RESULTS Twenty-five patients had received radiotherapy for colorectal carcinoma, 10 for prostate cancer, 7 for carcinoma of the cervix, and 6 for other tumors. Patients presented with 1 or more complications, including radiation enteritis (60%), strictures (53%), fistulae (17%), nonhealing wounds (15%), and de novo cancers in radiated fields (10%). Low anastomotic strictures (10%) were initially treated by dilation under sedation. Six patients (12%) ultimately required permanent diversion. All radiation-induced fistulae required an operation. CONCLUSIONS Determining the proper treatment requires careful judgment and assessment of the degree and type of injury, patient anatomy, and sphincter function. Patients presenting with colorectal anastomotic and primary bowel strictures as their main complication had the best results, while most patients with severe radiation enteritis and very distal strictures required permanent diversion.

The Role of Smoking in Crohn’s Disease as Defined by Clinical Variables

The development of Crohn’s disease (CD) is related to an interaction of genetic and environmental factors, with tobacco smoking being one of the most commonly studied environmental factors. In 1998, the Vienna classification was created to define CD by using three accepted clinical variables: age at diagnosis, disease behavior, and disease location. In this qualitative systematic review, articles examining the relationship between smoking and CD, using variables outlined in the Vienna classification, were identified utilizing multiple health databases. Current smoking was found to be associated with late-onset CD (≥40 years old) and current smokers were more likely to progress to stricturing or penetrating type CD than were nonsmoking patients. Conflicting evidence exists regarding the relationship between smoking with respect to CD disease location. The Vienna classification is an important tool in permitting comparisons and predicting clinical course among CD cases, especially when smoking status is taken into account.

Inflammatory bowel disease and African Americans: A systematic review

Background: Inflammatory bowel disease (IBD) is comprised of Crohns disease (CD) and ulcerative colitis (UC). There are conflicting reports on whether African Americans have a more severe disease course, presentation, and more frequent extraintestinal manifestations (EIM). We examined the precise nature of this relationship by conducting a systematic review. Methods: Using predefined inclusion criteria we searched multiple healthcare databases and Grey literature. Eight reports met the inclusion criteria. Using the parameters as defined in the Montreal classification and the presence or absence of EIM, we compared IBD in African Americans and Caucasians. Results: Over 2000 IBD cases were pooled from 8 reports with African Americans comprising 17%. African Americans and Caucasians had similar distribution of types of IBD, with CD being more common than UC in both groups (CD 76% versus 68% and UC 24% versus 32%, respectively). With respect to CD, both groups presented with nonstricturing and nonpenetrating disease behavior (55% versus 41%) more frequently and had similar rates of ileocolonic disease location (42% versus 38%), and presence of perianal disease (26% versus 29%). In UC patients, proctitis was the most frequent initial presentation in both races. Joint complications were the most frequent EIM in both African Americans (52%) and Caucasians (60%). Conclusions: This study dispels the commonly held views that African Americans with IBD generally have more colonic disease, more severe disease behavior, and more perianal disease than Caucasians. African Americans also have similar variety and frequency of EIMs as compared to Caucasians.

Opportunities for Improved Performance in Surgical Specialty Practice

Objective:To identify opportunities for improvement in quality performance profile while maintaining better clinical outcomes. Methods:A prospective study of 5285 surgical specialty procedures including hip and knee replacement, cholecystectomy, hysterectomy, nonaccess vascular and cardiac procedures, and colorectal resections in 16 Kentucky hospitals was undertaken. The following observations were made after univariate and stepwise logistic regression analysis, from the Surgical Care Improvement Project. Results:(1) Impaired functional status, age ≥65, and ASA class 4 or 5 status were significant predictors for both morbidity and mortality. (2) β blockade medication was maintained in only 70% of patients already receiving such medications; interestingly, vascular surgery and patients with known cardiac history did not have β blockade initiated 52% of the time. (3) Appropriate blood glucose control was not achieved in 31% of patients with diabetes and in 20% of nondiabetics. (4) deep vein thrombosis (DVT) prophylaxis was independent of high-risk status, with wide variation in practice. Patients undergoing total hip or knee replacement or colorectal resections had highest rates (0.7%) of pulmonary emboli. (5) A poor choice of antibiotic prophylaxis agent occurred in 8% of patients and was associated with a 3-fold increase in mortality (P < 0.01). (6) Hypothermia on arrival in PACU was present in 7% of patients after major colorectal resections and was ominously associated with an over 4-fold increase in mortality (P < 0.01). (7) Preoperative WBC >11,000/mm3 in elective operations was associated with nearly 3-fold increase in mortality (P < 0.05). Conclusion:Now more than ever, surgeons must verify performance measures and outcomes. This study of clinical outcomes permits identification of underappreciated contemporary risk factors and some obvious measures by which surgical practices can more objectively be evaluated.

Meta-analysis of cholecystectomy in symptomatic patients with positive hepatobiliary iminodiacetic acid scan results without gallstones.

OBJECTIVE To study the clinical results of surgical management in patients with right upper quadrant pain, a positive hepatobiliary iminodiacetic acid (HIDA) scan result, and no gallstones. DATA SOURCES Health care databases and gray literature. STUDY SELECTION Each article was scrutinized to determine whether it met inclusion criteria. Only abstracts, full articles, and gray literature that passed the detailed screening procedure were included. Case reports, letters, comments, reviews, and abstracts with insufficient details to meet inclusion criteria were excluded. Gallbladder ejection fraction assessed by means other than cholecystokinin HIDA scan were also excluded. DATA EXTRACTION Three reviewers independently abstracted the following data from each article: first author, year of publication, journal, type of study, location of study population, institution where the study was conducted, symptoms recorded, imaging modality used to establish the absence of gallstones, HIDA scan ejection fraction, number of cases and controls, number of males and females in each group, method of follow-up, and number of cases lost to follow-up. DATA SYNTHESIS Ten studies met inclusion criteria (N = 615). Follow-up ranged from 3 to 64 months. Surgical treatment was 15-fold more likely than medical treatment to result in symptom improvement, with 4% of patients reporting no symptom improvement with surgery. Sensitivity analysis in patients with complete symptom relief following surgery revealed an 8-fold greater odds difference than those treated medically (indicating variation in study reporting). CONCLUSIONS Patients without gallstones who have right upper quadrant pain and a positive HIDA scan result are more likely to experience symptom relief following cholecystectomy than those treated medically. There is, however, wide variability in data reporting, particularly with respect to symptom relief and duration of follow-up. Cholecystectomy is indicated in symptomatic patients without gallstones who have a low-ejection fraction HIDA scan.

Characterization of N-acetyltransferase 1 and 2 polymorphisms and haplotype analysis for inflammatory bowel disease and sporadic colorectal carcinoma

BackgroundN-acetyltransferase 1 (NAT1) and 2 (NAT2) are polymorphic isoenzymes responsible for the metabolism of numerous drugs and carcinogens. Acetylation catalyzed by NAT1 and NAT2 are important in metabolic activation of arylamines to electrophilic intermediates that initiate carcinogenesis. Inflammatory bowel diseases (IBD) consist of Crohns disease (CD) and ulcerative colitis (UC), both are associated with increased colorectal cancer (CRC) risk. We hypothesized that NAT1 and/or NAT2 polymorphisms contribute to the increased cancer evident in IBD.MethodsA case control study was performed with 729 Caucasian participants, 123 CRC, 201 CD, 167 UC, 15 IBD dysplasia/cancer and 223 controls. NAT1 and NAT2 genotyping were performed using Taqman based techniques. Eight single nucleotide polymorphisms (SNPs) were characterized for NAT1 and 7 SNPs for NAT2. Haplotype frequencies were estimated using an Expectation-Maximization (EM) method. Disease groups were compared to a control group for the frequencies at each individual SNP separately. The same groups were compared for the frequencies of NAT1 and NAT2 haplotypes and deduced NAT2 phenotypes.ResultsNo statistically significant differences were found for any comparison. Strong linkage disequilibrium was present among both the NAT1 SNPs and the NAT2 SNPs.ConclusionThis study did not demonstrate an association between NAT1 and NAT2 polymorphisms and IBD or sporadic CRC, although power calculations indicate this study had sufficient sample size to detect differences in frequency as small as 0.05 to 0.15 depending on SNP or haplotype.