Insulin and leptin have proliferative and anti-apoptotic effects. Ghrelin promotes gastric emptying and secretion of growth hormone and inhibits inflammation.
Dr Joel Rubenstein and colleagues from Michigan, USA assessed whether diabetes mellitus and serum levels of insulin, leptin, and ghrelin are associated with gastroesophageal reflux disease (GERD) and Barrett's esophagus.
The researchers conducted a case-control study in 822 men undergoing colorectal cancer screening who were recruited to also undergo upper endoscopy.
The team identified 70 with Barrett's esophagus, 80 additional men with Barrett's esophagus were recruited shortly after their clinical diagnoses.
|Leptin was positively associated with Barrett's esophagus|
Serum levels of insulin, leptin, and ghrelin were assayed in all 104 fasting men with Barrett's esophagus without diabetes and 271 without diabetes or Barrett's esophagus.
Logistic regression was used to estimate the effects of diabetes and levels of insulin, leptin, and ghrelin on GERD and Barrett's esophagus.
The team observed that among men with GERD, diabetes was inversely associated with Barrett's esophagus.
Among nondiabetics, hyperinsulinemia was positively associated with Barrett's esophagus, but the association was attenuated by adjustment for leptin and ghrelin.
The team found that leptin was positively associated with Barrett's esophagus, adjusting for obesity, GERD, and levels of insulin and ghrelin.
The team noted that this association was stronger in men with GERD.
Ghrelin was positively associated with Barrett's esophagus increment of 400 pg/mL, but inversely associated with GERD.
Dr Rubenstein's team concludes, "Based on a case-control study, leptin was associated with Barrett's esophagus, particularly in men with GERD."
"Serum insulin level was associated with Barrett's esophagus, but might be mediated by leptin."
"Serum ghrelin was inversely associated with GERD, as hypothesized, but positively associated with Barrett's esophagus, contrary to our hypothesis."
"Additional studies are needed in men and women to replicate these findings."