Red Blood Cell Distribution Width and Itʼs Association With Inflammatory Bowel Disease Management

Abstract

BACKGROUND: Inflammatory Bowel Diseases (IBD) require close monitoring over a person's lifetime to prevent long term negative sequelae and promote better outcomes. At present, the gold standard monitoring tool is endoscopic evaluation. Several non-invasive alternatives have been evaluated, however their benefit is unclear. The data we present evaluates red blood cell distribution width (RDW) as a predictive measure of active disease prior to endoscopy and if it is a useful prognostic tool. To date, the literature has noted a relationship between a high RDW and level of activity in many chronic inflammatory diseases, including IBD. This has been attributed to both the inflammatory nature of these diseases along with the associated anemia. Lastly, the benefits of RDW lie in its non-invasive nature and that it comes readily available in a commonly ordered lab test, a complete blood count (CBC), at no additional cost. METHODS: Data on patients with IBD who had an RDW within one month prior to colonoscopy from January 1, 2015 to December 31, 2015 was pulled in a retrospective chart review. Both clinical and descriptive data were obtained for the study as well as patients' Harvey Bradshaw Indices and Mayo Scores. Endoscopic data including the Mayo Endoscopic Score, Simplified Endoscopic Scoring System, and histologic data were also noted. Each endoscopy report was reviewed by two separate Gastroenterologists. Data exclusion criteria were: patients with hemoglobinopathies, organ transplant, hemoglobin less than 7, and for patients under the age of 18. The Mann-Whitney U Test was used to compare the difference among RDW values. Correlation between continuous variables was assessed using the Spearman Correlation Test. Statistical significance for all comparisons was set at 5%. RESULTS: Sixty patients met inclusion criteria. Median age for the cohort was 35 years (SD=17.1). Evaluating other patient demographics, 46.9% of participants were males and most were Caucasian (68%). There was a relationship between RDW and need for medication escalation after endoscopy. Medication increase post-colonoscopy was more frequently noted in patients with RDWs above the normal value. There was a significant difference in RDW between patients with Ulcerative Colitis who had a change in management compared with those who did not require a change in treatment (U=18, P=0.027). Similarly, there was a significant difference in RDW value for patients with Crohn's Disease who underwent change in treatment compared with patients who did not (U=101, P=0.043). CONCLUSION(S): Based on the findings from our retrospective data collection, elevated RDW was associated with the need for escalation of treatment in patients with IBD. This relationship was present on subgroup analysis for patients with Ulcerative Colitis and with Crohn's Disease.