NEW ORLEANS — High insulin levels, insulin resistance, and central body fat were each significantly associated with an increased risk of Barrett's esophagus in a case-control study presented at the meeting.
Previous studies have shown that obesity increases the risk of both esophageal adenocarcinoma and its precursor, Barrett's esophagus. In this study, Dr. Katarina Greer and her colleagues investigated whether central adiposity, hyperinsulinemia, and insulin resistance are independent risk factors for Barrett's esophagus.
“The mechanism through which obesity promotes cancer is still largely unknown,” said Dr. Greer of University Hospitals Case Medical Center in Cleveland, Ohio.
The researchers identified 135 adults with Barrett's esophagus from consecutive patients seen at a single tertiary care center. These patients were compared with two adult control groups—135 with gastroesophageal reflux disease (GERD) and 932 controls undergoing routine colonoscopies.
Overall, high levels of insulin and insulin resistance were significant independent risk factors for Barrett's esophagus, Dr. Greer noted. Persons in the highest quartile of serum insulin had a 2.8-fold increase in the risk of Barrett's esophagus, compared with those in the lowest quartile, after adjustment for age, sex, and waist-to-hip ratio.
Regarding insulin resistance, persons in the highest quartile of values for the homeostasis model assessment–insulin resistance (HOMA-IR) were about 3 times more likely to develop Barrett's esophagus than were those in the lowest quartile.
The mean fasting insulin levels were significantly higher in Barrett's esophagus patients than in colonoscopy patients. In addition, Barrett's esophagus patients were more insulin resistant than either of the control groups. The mean HOMA-IR in the Barrett's esophagus group was 2.7, compared with 1.8 in the control groups.
The average BMI was 30.8 kg/m
Disclosures: Dr. Greer had no financial conflicts of interest.