Metabolic syndrome and colorectal neoplasms: An ominous association.

Aim: To evaluate the association of metabolic syndrome (MS) and colorectal cancer and adenomas in a Western country, where the incidence of MS is over 27%.
Methods: This was a prospective study between March 2013 and March 2014. MS was diagnosed according to the National Cholesterol Education Program-ATP III. Demographic characteristics, anthropometric measurements, metabolic risk factors, and colonoscopic pathologic findings were assessed in patients with MS (group 1) who underwent routine colonoscopy at our department. This data was compared with consecutive patients without metabolic syndrome (group 2), with no differences regarding sex and age. Patients with incomplete colonoscopy, family history, or past history of colorectal neoplasm were excluded. Informed consent was obtained and the ethics committee approved this study. Statistical analysis was performed using Student's t-test and χ(2) test, with a P value ≤ 0.05 being considered statistically significant.
Results: Of 258 patients, 129 had MS; 51% males; mean-age 67.1 years (50-87). Among the MS group, 94% had high blood pressure, 91% had increased waist circumference, 60% had diabetes, 55% had low high-density lipoprotein cholesterol level, 50% had increased triglyceride level, and 54% were obese [body mass index (BMI) 30 kg/m(2)]. 51% presented 4 criteria of MS. MS was associated with increased prevalence of adenomas (43% vs 25%, P = 0.004) and colorectal cancer (13% vs 5%, P = 0.027), compared with patients without MS. MS was also positively associated with multiple (≥ 3) adenomas (35% vs 9%, P = 0.024) and sessile adenomas (69% vs 53%, P = 0.05). No difference existed between location (P = 0.086), grade of dysplasia (P = 0.196), or size (P = 0.841) of adenomas. In addition, no difference was found between BMI (P = 0.078), smoking (P = 0.146), alcohol consumption (P = 0.231), and the presence of adenomas.
Conclusion: MS is positively associated with adenomas and colorectal cancer. However, there is not enough information in western European countries to justify screening in patients with MS. To our knowledge, no previous study has evaluated this association in Portuguese patients.