Elevated Neutrophil-to-Lymphocyte Ratio in Metabolic Syndrome Is Associated with Increased Risk of Colorectal Adenoma.

BACKGROUND: Metabolic syndrome (MetS) is an important cardiovascular risk factor for insulin resistance and has been linked to colorectal adenoma via inflammation. The neutrophil-to-lymphocyte ratio (NLR) has been suggested as an important inflammatory marker. We initiated this investigation to determine the relationship between colorectal adenoma and NLR in patients with MetS.

METHODS: We examined participants who visited the Health Promotion Center at Kosin University Gospel Hospital, Busan, Korea. Subjects who underwent both colonoscopy and liver ultrasonography were included. Colorectal adenoma was defined as the presence of a colon polyp with a histologically adenomatous component. MetS was defined according to the modified National Cholesterol Education Program Adult Treatment Panel III definition for South Asians. Anthropometric measurements and biochemical tests of liver and metabolic function were assessed.

RESULTS: A total of 1007 subjects were included in the study sample. Their mean age was 48.3 ± 9.7 years and 262 (26.0%) subjects had MetS, while 439 (43.6%) subjects had pathologically proven colorectal adenoma. Subjects with MetS were older, more likely to be male, and had significantly higher prevalences of colorectal adenoma (49.2% vs. 41.6%, P = 0.032), nonalcoholic fatty liver disease (62.8% vs. 19.5%, P < 0.001), and higher NLR (2.0 ± 0.9 vs. 1.7 ± 0.7, P < 0.001) compared to those without MetS. High NLR (≥2.0) was an independent factor affecting the prevalence of colorectal adenoma [odds ratio (OR) 1.38, confidence interval (95% CI) 1.02-1.88, P = 0.040], especially in subjects with MetS (OR 1.91, 95% CI 1.12-3.28, P = 0.018).

CONCLUSION: High NLR was associated with increased colorectal adenomatous polyps, particularly in subjects with MetS. Screening colonoscopies for the prevention of colorectal adenoma may be warranted for patients with high NLR and MetS.