Gestational Diabetes May Be Risk Factor for Pancreatic Cancer

August 16, 2007

NEW YORK -- Women who develop gestational diabetes may be at increased risk for pancreatic cancer decades later, reported researchers here.

NEW YORK, Aug. 16 -- Women who develop gestational diabetes may be at increased risk for pancreatic cancer decades later, reported researchers here.

The relative risk of pancreatic cancer was 7.1 (95% CI 2.8-18) among 410 women who had a history of gestational diabetes, according to a study published online in BMC Medicine.

After adjusting for age, the risk of pancreatic cancer increased to 7.9 (95% CI 3.1-19.8, P

Previous studies have linked type 2 diabetes to increased risk of pancreatic cancer, but the authors said this was the first study to suggest that gestational diabetes increased that risk.

They acknowledged, however, that a small prospective cohort study of Scottish women found that women who had higher fasting glucose levels during pregnancy had an increased risk for any neoplasm.

The current study had "the advantage of a prospective design, long follow-up and complete obstetric history on all births," the researchers wrote. Moreover, the information on gestational diabetes was taken from medical records rather than self-report.

Nonetheless, the authors said that they "do not have an exact definition of diabetes and modern criteria for gestational diabetes mellitus were not applied in that era."

Data were only available for observed pregnancies and they were unable to control for smoking history and body mass index, all potential limitations.

Moreover, they noted, because there were only 54 cases of pancreatic cancer during the follow-up -- and just five of those cases developed in women who had a history of gestational diabetes -- chance or confounding "cannot be ruled out as the RR at the low end of the confidence interval was 2.8."

Finally, the authors wrote that the prevalence of gestational diabetes is increasing. "Other than type 2 diabetes mellitus, the sequelae of gestational diabetes mellitus remain largely unknown. If the results of the current study are confirmed, then it would be expected that the incidence of pancreatic cancer could increase," they wrote.