Bonnie Cao

Risk Factors for Rehospitalization Within 90 Days in Patients with Inflammatory Bowel Disease.

Background:Care of patients with inflammatory bowel disease (IBD) poses a significant burden to the health-care system. Repeat hospitalization in subgroups of IBD patients seems to be a large part of this issue; however, there are limited data examining the characteristics of these patients. The aim of this study was to characterize admission patterns in patients with IBD at a tertiary-care center and to identify preventable risk factors of 90-day readmission after an index IBD admission. Methods:Retrospective analysis was performed extracting data from an electronic medical record over a 2-year period. Results:Three hundred fifty-six patients were admitted at least once during the 2-year study period for an unplanned IBD-related reason. Of these, 48.9% were admitted once, 38.2% were admitted 2 to 4 times, and 12.9% were admitted 5 or more times during the study period. Patients with any admission within 90 days before index were excluded; n = 33. One hundred two patients had experienced a readmission by 90 days after index admission. Numerous demographic and medical factors were examined for association with readmission. The final Cox model included 3 variables: depression (HR = 1.99, 1.33–3.00), chronic pain (HR = 1.88, 1.14–3.10), and steroid use in the previous 6 months (HR = 1.33, 0.92–2.04). Conclusions:Our findings suggest that patients with depression and chronic pain are at greatest risk for a readmission within 90 days after an initial IBD admission. Disease activity, represented by steroid use in the previous 6 months, was not related to readmission. Addressing these problems in the outpatient setting may reduce future hospitalizations.

Higher 25-hydroxyvitamin D levels are associated with greater odds of remission with anti-tumour necrosis factor-α medications among patients with inflammatory bowel diseases

Vitamin D has been linked to disease activity among patients with inflammatory bowel diseases (IBD). Prior investigation has also suggested that vitamin D levels may affect duration of therapy with anti‐tumour necrosis factor‐α (anti‐TNF‐α) medications among patients with IBD.

Mucosal Gene Expression in Pediatric and Adult Patients With Ulcerative Colitis Permits Modeling of Ideal Biopsy Collection Strategy for Transcriptomic Analysis

Background Transcriptional profiling has been performed on biopsies from ulcerative colitis patients. Limitations in prior studies include the variability introduced by inflammation, anatomic site of biopsy, extent of disease, and medications. We sought to more globally understand the variability of gene expression from patients with ulcerative colitis to advance our understanding of its pathogenesis and to guide clinical study design. Methods We performed transcriptional profiling on 13 subjects, including pediatric and adult patients from 2 hospital sites. For each patient, we collected 6 biopsies from macroscopically inflamed tissue and 4 biopsies from macroscopically healthy-appearing tissue. Isolated RNA was used for microarray gene expression analysis utilizing Affymetrix Human Primeview microarrays. Ingenuity pathway analysis was used to assess over-representation of gene ontology and biological pathways. RNAseq was also performed, and differential analysis was assessed to compare affected vs unaffected samples. Finally, we modeled the minimum number of biopsies required to reliably detect gene expression across different subject numbers. Results Transcriptional profiles co-clustered independently of the hospital collection site, patient age, sex, and colonic location, which parallels prior gene expression findings. A small set of genes not previously described was identified. Our modeling analysis reveals the number of biopsies and patients per cohort to yield reliable results in clinical studies. Conclusions Key findings include concordance, including some expansion, of previously published gene expression studies and similarity among different age groups. We also established a reliable statistical model for biopsy collection for future clinical studies.

Sa1247 Risk Factors for Re-Hospitalization Within 90 Days in Patients With Inflammatory Bowel Disease Are Not Related to Disease Activity

Background: Previous studies have demonstrated that the care of inflammatory bowel disease (IBD) patients poses a significant burden to the healthcare system. More than one and a half million people in the United States suffer from ulcerative colitis (UC) and Crohns disease (CD) and these patients require more frequent hospital admissions than non-IBD patients, and have an increased average length of stay. Moreover, hospital care for IBD patients has been shown to be twice as expensive as that for non-IBD controls. Repeat hospitalization in subgroups of IBD patients appears to be a large part of this issue, however there is only limited literature examining the characteristics of IBD patients that are associated frequent hospital use. Aims: To characterize admission patterns in patients with IBD at a tertiary care referral center, and identify preventable causes of 90-day readmission after an index IBD admission. Methods: Data was gathered retrospectively from a tertiary-care IBD referral center. Study subjects included all patients age 18 or older with a known diagnosis of IBD, who were admitted at least once between January 1st, 2011 and December 31st, 2012 for a non-elective, IBD-related reason. Hospital billing records were searched using the Research Patient Data Registry. Univariate analysis was performed. A cox proportional hazards model was developed with covariates felt a priori to be related to readmission. Forward selection was performed. Results: 356 patients were admitted at least once during the 2-year study period for an unplanned, IBD-related reason. 208 (58.4%) had CD and 148 (41.6%) had UC. The mean age at time of index admission was 41.7 years (SD +/17). Women accounted for 62% (n = 220). 125 patients had experienced a re-admission by 90 days and no patients were censored prior to 90 days. The initial model contained 19 covariates. Depression and steroid use in the prior 6 months (a marker of active disease) were forced in. After forward selection the final model included four variables, depression (HR=2.06, 1.42-2.98), chronic pain (HR=1.87,1.19-2.94) etoh use (HR=2.43, 1.21-5.29) and Remicade use (HR=1.15, 0.76-1.72).The proportional hazard assumption was then tested on using Martingale residuals for each of the four variables in the final model and all resulted in non-significant p-value. Conclusions: These findings suggests that patients with depression, chronic pain, and who drink alcohol are at greatest risk for a re-admission within 90 days after an initial IBD admission. Disease activity, represented by steroid use in the prior 6 months, was not related to re-admission. Our study identified that comorbid psychiatric disease, chronic pain, and substance abuse are associated with repeat hospitalization. Addressing these problems in the outpatient setting may reduce future hospitalizations in IBD patients. Table 1: Cox Proportional Hazard Model for 90-day Readmission