Gestational diabetes appears to increase risk for pancreatic cancer although type 1 diabetes does not appear to increase risk from the baseline associated with normal glucose metabolism, according to an article in the August 16 issue of BMC Medicine.

The study entailed review of women whose pregnancies were managed in Israel in the 1960s and 1970s. The research team, led by M.C. Perrin, PhD, NYU School of Medicine, New York, USA, traced over 37,000 mothers who gave birth between 1964 and 1976 in Jerusalem as part of the Jerusalem Perinatal Study.

Record review revealed 410 women were diagnosed with gestational diabetes in one or more pregnancy. Of the 410 women with gestational diabetes, five eventually developed pancreatic cancer. There were 54 cases of pancreatic cancer overall in the cohort; none of the women with type 1 diabetes at the time they gave birth went on to develop pancreatic cancer. Relative risk for women with gestational diabetes versus normal glucose metabolism was 7.1.

Those with gestational diabetes often go on to develop type 2 diabetes mellitus. Medical debate surrounds the causal relationship between diabetes and pancreatic cancer. On the one hand, patients with newly diagnosed pancreatic cancer frequently have diabetes of recent onset and when the tumor is removed the symptoms of diabetes often improve. On the other hand, individuals with long standing diabetes have also been shown to be at increased risk of pancreatic cancer. In this study the gestational diabetes clearly came first, between 14 and 35 years before the pancreatic cancer.