BS O05 - Prevalence and Patterns of Iron Deficiency in Patients Living with Obesity: Insights from Bariatric Surgery Candidates

Abstract Background Iron deficiency anaemia (IDA) is a recognised complication of obesity, and its associated co-morbidities. Iron deficiency has been implicated in immunologic dysfunction in obesity. However, the patterns of iron deficiency in people with obesity, independent of IDA, and its implications for patients with obesity remain unclear. This study aimed to investigate potential causes of iron deficiency, including relationship with glycaemic control and relationship with systemic inflammation. Relationship between iron deficiency and body mass index (BMI) was also considered. Method A retrospective review of a prospectively maintained database of consecutive patients undergoing bariatric surgery was performed. Pre-operative haematologic assessments were reviewed, and linear regression models were used to identify the associations of iron deficiency in patients with obesity. Statistical analysis was performed using SPSS. 384 consecutive patients over a 2-year time period were included in the analysis. 72.1% of patients were female and the mean age was 49.44±10.2. The mean weight of included patients was 144.1±31.02 kg, and the mean BMI was 50.66±9.61 kg/m2 Results ​2.45% of patients met the criteria for iron deficiency anaemia. However, 15.49 % had low serum iron(<9 mmol/L), 12.1% had low ferritin(<30mg/L), 1.38% had low transferrin(<2g/L), 15.17% had high Total Iron Binding Capacity(>71.6mmol/L), 37.93% had low transferrin saturation(<20%). High BMI was a significant predictor of low serum iron(β=-0.206, p=0.031). Dysregulated glycaemic metabolism(HbA1c and glucose) was not a significant predictor of iron deficiency. Baseline inflammation (elevated CRP) was associated with low serum iron(β=-0.320, p=<0.001) and low transferrin(β=-0.205, p=0.028). Conclusion Iron deficiency in patients with obesity is common, but not iron deficiency anaemia dependent. It does not appear to be linked to patients’ glycaemic regulation, as previously thought. Our findings suggest it may instead be attributable to the systemic inflammation caused by obesity.