Introduction

Iron deficiency anaemia (IDA) is a common comorbidity in inflammatory bowel diseases (IBD). Previous studies have already showed the predictive value of anaemia on hospitalization and mortality rates, however, these studies did not focus on the effect of IDA on patients with clinical and biochemical remission, however, due to the ethiopathology, certain effects are hypothesized.

Aims & Methods

This was a multicenter retrospective real-life cohort study assessing the effect of IDA on clinically and biochemically inactive IBD patients. We included patients from the outpatient setting who has been followed-up for a year. Patients with need of blood transfusion at baseline were excluded. IDA was defined as no clinical and biochemical activity, ferritin <30 μg/mL and transferrin saturation <20% with the presence of anemia. Primary outcome was disease aggravation, defined as need of change in the current treatment/hospitalization/abdominal surgery. Secondary outcome was proportion of major complications, defined as need of hospitalization/abdominal surgery. Pearson’s chi squared sample size calculation (n=720) was performed on our pilot results based on 200 IBD patients.

Results

In total, 711 patients (median age: 43.1 years [IQR: 32.3 - 49.6]; male/female ratio: 332/379; CD: 397, UC: 311; IDA/non-IDA 85/623) were enrolled. Mean follow-up period was 1.1±0.28 years. The presence of IDA increased the risk of disease aggravation (OR: 1.7) and major complications (OR: 2.8). Furthermore, male sex (OR: 0.6) and older age (OR: 0.8) were protective, and ileocoecal resection (OR: 2.0) and higher C-reactive protein levels (OR: 1.5) increased the disease aggravation.

Conclusion

IDA predicts the risk of relapse at some degree in patients with clinical and biochemical remission in the outpatient setting. IDA may help to identify underlying disease activity in patients with clinical and biochemical remission in time, therefore, we recommend to be implemented in the treat-to-target approach.