Administrative database studies in IBD: a cautionary tale

Changing nationwide trends in endoscopic, medical and surgical admissions for inflammatory bowel disease: 2003-2013

Background and study aims

In the last decade, there have been major advances in inflammatory bowel disease (IBD) management but their impact on hospital admissions requires evaluation. We aim to investigate nationwide trends in IBD surgical/medical elective and emergency admissions, including endoscopy and cytokine inhibitor infusions, between 2003 and 2013.

Patients and methods

We used Hospital Episode Statistics and population data from the UK Office for National Statistics.

Results

Age-sex standardised admission rates increased from 76.5 to 202.9/100 000 (p<0.001) and from 69.5 to 149.5/100 000 (p<0.001) for Crohn’s disease (CD) and ulcerative colitis (UC) between 2003–2004 and 2012–2013, respectively. Mean length of stay (days) fell significantly for elective (from 2.6 to 0.7 and from 2.0 to 0.7 for CD and UC, respectively) and emergency admissions (from 9.2 to 6.8 and from 10.8 to 7.6 for CD and UC, respectively). Elective lower gastrointestinal (GI) endoscopy rates decreased from 6.3% to 3.7% (p<0.001) and from 18.4% to 17.6% (p=0.002) for CD and UC, respectively. Elective major abdominal surgery rates decreased from 2.8% to 1.0% (p<0.001) and from 4.9 to 2.4 (p=0.010) for CD and UC, respectively, with emergency rates also decreasing significantly for CD. Between 2006-2007 and 2012-2013, elective admission rates for cytokine-inhibitor infusions increased from 11.1 to 57.2/100 000 and from 1.4 to 12.1/100 000 for CD and UC, respectively.

Conclusions

Rising IBD hospital admission rates in the past decade have been driven by an increase in the incidence and prevalence of IBD. Lower GI endoscopy and surgery rates have fallen, while cytokine inhibitor infusion rates have risen. There has been a concurrent shift from emergency care to shorter elective hospital stays. These trends indicate a move towards more elective medical management and may reflect improvements in disease control.

Surgical Rates for Crohn's Disease are Decreasing: A Population-Based Time Trend Analysis and Validation Study

OBJECTIVES

Temporal changes for intestinal resections for Crohn's disease (CD) are controversial. We validated administrative database codes for CD diagnosis and surgery in hospitalized patients and then evaluated temporal trends in CD surgical resection rates.

METHODS

First, we validated International Classification of Disease (ICD)-10-CM coding for CD diagnosis in hospitalized patients and Canadian Classification of Health Intervention coding for surgical resections. Second, we used these validated codes to conduct population-based surveillance between fiscal years 2002 and 2010 to identify adult CD patients undergoing intestinal resection (n=981). Annual surgical rate was calculated by dividing incident surgeries by estimated CD prevalence. Time trend analysis was performed and annual percent change (APC) with 95% confidence intervals (CI) in surgical resection rates were calculated using a generalized linear model assuming a Poisson distribution.

RESULTS

In the validation cohort, 101/104 (97.1%) patients undergoing surgery and 191/200 (95.5%) patients admitted without surgery were confirmed to have CD on chart review. Among the 116 administrative database codes for surgical resection, 97.4% were confirmed intestinal resections on chart review. From 2002 to 2010, the overall CD surgical resection rate was 3.8 resections per 100 person-years. During the study period, rate of surgery decreased by 3.5% per year (95% CI: -1.1%, -5.8%), driven by decreasing emergent operations (-10.1% per year (95% CI: -13.4%, -6.7%)) whereas elective surgeries increased by 3.7% per year (95% CI: 0.1%, 7.3%).

CONCLUSIONS

Overall surgical resection rates in CD are decreasing, but a paradigm shift has occurred whereby elective operations are now more commonly performed than emergent surgeries.

Descriptive epidemiology of children hospitalized for inflammatory bowel disease in Japan: Inpatient database analysis

BACKGROUND

Inflammatory bowel disease (IBD) - Crohn's disease (CD) and ulcerative colitis (UC) - are chronic inflammatory disorders of the intestine. Patients with IBD are at risk of hospitalization for disease exacerbation or IBD-associated complications. In the pediatric population, however, there are limited data on IBD hospitalizations. We therefore investigated the descriptive epidemiology of hospitalizations relevant to pediatric IBD.

METHODS

The national inpatient claims database in Japan was searched for children (≤ 18 years old) with a diagnosis of IBD. The study period was 2007-2010. Data on demographic characteristics and descriptive statistics of the hospital course were extracted and analyzed.

RESULTS

A total of 3559 admissions of 2175 patients met the definition of pediatric IBD: there were 1999 admissions for CD and 1560 admissions for UC. Internists were responsible for patient care in 56.6% of admissions, followed by pediatricians (27.5%). Of 3559 admissions, unscheduled hospitalizations accounted for 79.7%, and 7.6% of hospitalizations were attributable to complications of IBD, including intestinal, extraintestinal and other manifestations. The median age at first admission was 16 years (IQR, 13-17 years), in both the CD and UC groups. Compared with UC patients, CD patients had a higher number of hospitalizations (P < 0.001), but hospital stay was shorter (median: 6 vs 16 days, P < 0.001). There were seven fatal cases of IBD, accounting for 0.32% in the present series, and sepsis was the cause in five.

CONCLUSIONS

This study provides a description of pediatric inpatients with IBD and their hospital course in Japan.

Increasing hospitalizations in inflammatory bowel disease among children in the United States, 1988-2011

BACKGROUND

Our objective was to characterize national trends in inflammatory bowel disease (IBD)-related hospitalizations for children. We hypothesized that over time, improvements in care would be associated with a decrease in hospitalization rates, similar to what has been observed in Canadian children with IBD.

METHODS

Retrospective, serial, cross-sectional analysis of annual, nationally representative samples of children with IBD.

RESULTS

Overall, discharges for all children irrespective of diagnosis decreased from 1988 to 2011 (P for trend <0.001). In contrast, discharges for children with IBD rose over the same time period from 6.1 (95% confidence interval [CI], 4.0-8.2) to 8.2 (95% CI, 5.5-10.9) per 100,000 individuals per year (P for trend <0.001). More of this rise occurred in hospitalizations that did not have IBD-related endoscopy or surgery performed (P for trend <0.001). Although mean length of stay decreased over the study period (P for trend <0.001), total hospital days increased over the latter half of the study with a significant increase over the entire study period (P for trend <0.001).

CONCLUSIONS

Contrary to clinically informed hypotheses, nationally representative rates of hospitalization for pediatric patients with IBD have increased since the mid-1990s. This directly contrasts with stable rates over the preceding years. Most of the expansion in hospital care seems to be related to hospitalizations that do not include procedures. Several lines of future research may greatly facilitate a better understanding of the epidemiologic, therapeutic, and health care resource issues at play.

Evaluation of the utility of hospital databases to provide data in assessing the quality of strabismus surgery

AIMS AND BACKGROUND

Rates of re-operation, which may be related to an unsatisfactory surgical outcome, can provide a long-term index of the quality of strabismus surgery. This study aims to evaluate the utility of the Scottish Morbidity Records (SMR1) in determining nature and rates of re-operation for strabismus at the Royal Hospital for Sick Children (RHSC), Glasgow.

METHODS

SMR1 data on strabismus surgery performed on children aged between 0 and 17 years at the RHSC, Glasgow, between January 2000 and March 2009 were analysed.

RESULTS

In total, 1376 strabismus procedures were carried out on 1274 individuals. The median time between first and subsequent procedures was 19 months; the commonest reasons being under-correction or recurrence. The Kaplan-Meier rate of undergoing re-operation was 7.4% after 9 years with a 95% confidence interval of 5.4-9.9%.

CONCLUSIONS

The SMR1 is a useful source of hospital-based and population data. With supplementation from parallel databases, routine administrative databases like the SMR1 can provide better quality data to inform practice.

IBDsite: a Galaxy-interacting, integrative database for supporting inflammatory bowel disease high throughput data analysis

BACKGROUND

Inflammatory bowel diseases (IBD) refer to a group of inflammatory conditions concerning colon and small intestine, which cause socially uncomfortable symptoms and often are associated with an increased risk of colon cancer. IBD are complex disorders, which rely on genetic susceptibility, environmental factors, deregulation of the immune system, and host relationship with commensal microbiota. The complexity of these pathologies makes difficult to clearly understand the mechanisms of their onset. Therefore, the study of IBD must be faced exploiting an integrated and multilevel approach, ranging from genes, transcripts and proteins to pathways altered in affected tissues, and carefully considering their regulatory mechanisms, which may intervene in the pathology onset. It is also crucial to have a knowledge base about the symbiotic bacteria that are hosted in the human gut. To date, much data exist regarding IBD and human commensal bacteria, but this information is sparse in literature and no free resource provides a homogeneously and rationally integrated view of biomolecular data related to these pathologies.

METHODS

Human genes altered in IBD have been collected from literature, paying particular interest for the immune system alterations prompted by the interaction with the gut microbiome. This process has been performed manually to assure the reliability of collected data. Heterogeneous metadata from different sources have been automatically formatted and integrated in order to enrich information about these altered genes. A user-friendly web interface has been created for easy access to structured data. Tools such as gene clustering coefficients, all-pairs shortest paths and pathway lengths calculation have been developed to provide data analysis support. Moreover, the implemented resource is compliant to the Galaxy framework, allowing the collected data to be exploited in the context of high throughput bioinformatics analysis.

RESULTS

To fill the lack of a reference resource for 'omics' science analysis in the context of IBD, we developed the IBDsite (available at http://www.itb.cnr.it/ibd), a disease-oriented platform, which collects data related to biomolecular mechanisms involved in the IBD onset. The resource provides a section devoted to human genes identified as altered in IBD, which can be queried at different biomolecular levels and visualised in gene-centred report pages. Furthermore, the system presents information related to the gut microbiota involved in IBD affected patients. The IBDsite is compliant with all Galaxy installations (in particular, it can be accessed from our custom version of Galaxy, http://www.itb.cnr.it/galaxy), in order to facilitate high-throughput data integration and to enable evaluations of the genomic basis of these diseases, complementing the tools embedded in the IBDsite.

CONCLUSIONS

Lots of sparse data exist concerning IBD studies, but no on-line resource homogeneously and rationally integrate and collect them. The IBDsite is an attempt to group available information regarding human genes and microbial aspects related to IBD, by means of a multilevel mining tool. Moreover, it constitutes a knowledge base to filter, annotate and understand new experimental data in order to formulate new scientific hypotheses, thanks to the possibility of integrating genomics aspects by employing the Galaxy framework. Discussed use-cases demonstrate that the developed system is useful to infer not trivial knowledge from the existing widespread data or from novel experiments.

Postoperative complications following colectomy for ulcerative colitis: a validation study

Background

Ulcerative colitis (UC) patients failing medical management require colectomy. This study compares risk estimates for predictors of postoperative complication derived from administrative data against that of chart review and evaluates the accuracy of administrative coding for this population.

Methods

Hospital administrative databases were used to identify adults with UC undergoing colectomy from 1996–2007. Medical charts were reviewed and regression analyses comparing chart versus administrative data were performed to assess the effect of age, emergent operation, and Charlson comorbidities on the occurrence of postoperative complications. Sensitivity, specificity, and positive/negative predictive values of administrative coding for identifying the study population, Charlson comorbidities, and postoperative complications were assessed.

Results

Compared to chart review, administrative data estimated a higher magnitude of effect for emergent admission (OR 2.52 [95% CI: 1.80–3.52] versus 1.49 [1.06–2.09]) and Charlson comorbidities (OR 2.91 [1.86–4.56] versus 1.50 [1.05–2.15]) as predictors of postoperative complications. Administrative data correctly identified UC and colectomy in 85.9% of cases. The administrative database was 37% sensitive in identifying patients with ≥ 1Charlson comorbidity. Restricting analysis to active comorbidities increased the sensitivity to 63%. The sensitivity of identifying patients with at least one postoperative complication was 68%; restricting analysis to more severe complications improved the sensitivity to 84%.

Conclusions

Administrative data identified the same risk factors for postoperative complications as chart review, but overestimated the magnitude of risk. This discrepancy may be explained by coding inaccuracies that selectively identifying the most serious complications and comorbidities.

Kawasaki disease in Israel

OBJECTIVE

To characterize the epidemiology and estimate the incidence of Kawasaki disease (KD) among children in Israel.

METHODS

Using the Israel National Hospital Discharge Register, we investigated the epidemiologic features of KD among children <18 years of age between 1996 to 2009 in Israel. Incidence rates were calculated using the corresponding census data.

RESULTS

During 1996 through 2009, 685 children <18 years of age were hospitalized for KD in Israel. Of these children, 88% were aged <5 years; the male/female ratio was 1.7:1; and most cases occurred in late winter-early spring. The overall incidence of KD was 6.4 per 100,000 children <5 years of age. Since 2000, there was a gradual increase in KD incidence as well as in the ratio of KD-associated hospitalizations to all-cause pediatric hospitalizations. For male infants <1 year of age, KD rates almost doubled: from 5.8 per 100,000 cases in 1996-1998 to an average of 11.9 cases per 100,000 in the following years (P = 0.002). The overall proportion of patients with coronary artery aneurysm was 2.9%, higher rates of coronary artery aneurysm were observed in patients <1 or >5 years of age and in male patients.

CONCLUSIONS

Major epidemiologic features of KD among Israeli children are similar to those reported for the white population in Europe and the United States. KD incidence increased during the study period, especially among male infants <1 year of age.

Increased health burden associated with Clostridium difficile diarrhoea in patients with inflammatory bowel disease

BACKGROUND

Clostridium difficile (C. difficile) infection in hospitals in developed countries continues to be a major public health hazard despite increased control measures including review of antibiotic policies and hygiene measures. Patients with colitis are thought to be particularly vulnerable to C. difficile associated diarrhoea (CDAD). Identifying the clinical burden among hospitalised patients admitted with inflammatory bowel disease is an essential first step towards identifying and treating severe C. difficile infection in such individuals.

AIM

To determine excess morbidity and in-hospital mortality associated with hospital acquired CDAD in patients with inflammatory bowel disease (IBD-CDAD-HAI) admitted to NHS hospitals in England compared with those admitted for inflammatory bowel disease alone.

METHODS

Time trends study of all admissions to NHS hospitals between 2002/03 and 2007/08. We developed case definitions for IBD-CDAD-HAI patients. The primary outcomes were in-hospital mortality and length of stay. The secondary outcome was gastrointestinal surgery.

RESULTS

Patients in the IBD-CDAD-HAI group were more likely to die in hospital (adjusted OR 6.32), had 27.9 days longer in-patient stays and higher gastrointestinal surgery rates (adjusted OR 1.87) than patients admitted for inflammatory bowel disease alone.

CONCLUSION

Patients with inflammatory bowel disease admitted to NHS hospitals in England with co-existent C. difficile infection are at risk of greater in-hospital mortality and morbidity than patients admitted for inflammatory bowel disease alone.

Cataract surgery complications in nonagenarians

PURPOSE

To investigate whether nonagenarians relative to octogenarians are at increased risk of ocular complications from cataract surgery in the US Veterans Health Administration (VHA).

DESIGN

A retrospective cohort study.

PARTICIPANTS

A total of 554 nonagenarians and 11 407 octogenarians who received cataract surgery in the VHA.

METHODS

Nonagenarians and octogenarians who received 1 cataract surgery without a second surgery within 90 days between October 1, 2005, and September 30, 2007, were identified using the National Patient Care Database (NPCD). Data collected include demographics, preoperative systemic and ocular comorbidities, intraoperative complications, and 90-day postoperative complications. The adjusted odds ratio (OR) of complications in nonagenarians using octogenarians as a reference group was calculated using logistic regression modeling.

MAIN OUTCOME MEASURES

Intraoperative and postoperative ocular complications within 90 days of cataract surgery in nonagenarians versus octogenarians.

RESULTS

The most common systemic comorbidity for both age groups was diabetes mellitus (DM), and the most common ocular comorbidity for both age groups was age-related macular degeneration (AMD). Octogenarians had a higher prevalence of most systemic comorbidities, and nonagenarians had a higher prevalence of most ocular comorbidities. The most common intraoperative and postoperative complications for both age groups were vitreous loss or posterior capsular tear and posterior capsular opacification. The risk of having any intraoperative or postoperative complication was 13.5% for octogenarians and 13.4% for nonagenarians (P = 0.9001). The OR of having any intraoperative or postoperative complication in nonagenarians with octogenarians as a reference group was 0.94 (95% confidence interval, 0.73-1.22).

CONCLUSIONS

Nonagenarians relative to octogenarians are not at increased risk of ocular complications from cataract surgery in the VHA. Further studies are needed to evaluate other outcome parameters, such as visual function and quality of life, in nonagenarians undergoing cataract surgery.

Systematic review: Clostridium difficile and inflammatory bowel disease

BACKGROUND

There is increasing concern about the apparently rising incidence and worsening outcome of Clostridium difficile infection (CDI) associated with inflammatory bowel disease (IBD). We have systematically reviewed the literature to evaluate the incidence, risk factors, endoscopic features, treatment and outcome of CDI complicating IBD.

AIM

To systematically review: clostridium difficile & inflammatory bowel disease.

METHODS

Structured searches of Pubmed up to September 2010 for original, cross-sectional, cohort and case-controlled studies were undertaken.

RESULTS

Of 407 studies, 42 met the inclusion criteria: their heterogeneity precluded formal meta-analysis. CDI is commoner in active IBD, particularly ulcerative colitis, than in controls. Certainty about a temporal trend to its increasing incidence in IBD is compromised by possible detection bias and miscoding. Risk factors include immunosuppressants and antibiotics, the latter less commonly than in controls. Endoscopy rarely shows pseudomembranes and is unhelpful for diagnosing CDI in IBD. There are no controlled therapeutic trials of CDI in IBD. In large studies, outcome of CDI in hospitalised IBD patients appears worse than in controls.

CONCLUSIONS

The complication of IBD by Clostridium difficile infection has received increasing attention in the past decade, but whether its incidence is really increasing or its outcome worsening remains unproven. Therapeutic trials of Clostridium difficile infection in IBD are lacking and are needed urgently.