Monocyte/High-Density Lipoprotein Ratio as an Inflammatory Marker in Patients with Irritable Bowel Syndrome

Objective: Irritable bowel syndrome (IBS) is a chronic, functional disorder of the gastrointestinal tract. Recent investigations have highlighted the potential involvement of inflammation, although the etiology of IBS remains unknown. This study aims to assess the connection between IBS and Monocyte/High-Density Lipoprotein (HDL) ratio (MHR), a new inflammatory marker. Material and Method: The study was conducted in the outpatient gastroenterology unit of a tertiary center between March-2021 and March-2022. Patients with IBS, according to the Rome IV criteria were examined retrospectively. Age- and sex-matched healthy controls were used to compute MHR and compare the results. Results: A total of 255 participants, 155 diagnosed with IBS and 100 in the control group, were included. The median (min-max) monocyte counts (cells/mm³) in the IBS and control groups were 380.0 (310.0-460.0) and 332.0 (232.0-449.3), respectively (p = 0.008). The median(min-max) HDL levels(mg/dl) in IBS and control groups were 45.0(36.0-55.0) and 49.0(43.0-57.0), respectively(p=0.001). The median MHR was higher in the IBS group (9.5) compared to healthy controls (6.73, p<0.001). Logistic regression analysis revealed MHR as an independent predictor of the presence of IBS (OR: 1.406, 95% CI: [insert confidence interval]). The cut-off value for MHR to detect IBS with 62.6% sensitivity and 63.0% specificity was 7.57, and ROC analysis revealed an AUROC value of 0.646 (95% CI: 0.577-0.715, p<0.001). Discussion: The study's primary findings were that IBS patients had significantly lower levels of HDL cholesterol and significantly higher levels of monocyte counts when compared to the control group. Consequently, monocyte/HDL ratios (MHR) were statistically substantially greater in IBS patients than in the control group. Furthermore, when the cut-off value was set at 7.6, MHR was found to be an independent predictor for IBS, with 62.6% sensitivity and 63.0% specificity. Conclusion: MHR can be a simple, inexpensive, and effective tool to demonstrate the inflammatory state in patients with IBS.