Gestational age, birth weight may predict type 1 diabetes risk
Early life growth restriction or altered gut microbiota in preterm infants may be related to insulin resistance suggesting an association between gestational age and type 1 diabetes, according to recent study findings published in Diabetes Care.
Although the association is small, it is not likely due to familial confounding factors, researchers wrote.
Ali S . Khashan, PhD, of University College Cork in Ireland, and colleagues evaluated data on all singleton births in Sweden between 1973 and 2009 (n = 3,624,675) to determine the effects of gestational age, birth weight, small for gestational age and large for gestational age on the risk for type 1 diabetes in childhood. Researchers further conducted a sibling control study on 11,403 children with type 1 diabetes and 17,920 siblings.
Gestational age was categorized as very preterm (22-32 weeks gestation), preterm (33-36 weeks), early term (37-38 weeks), term (reference group; 39-40 weeks) and postterm (41 or more weeks).
Throughout the study period, there were 13,944 cases of childhood type 1 diabetes.
Type 1 diabetes was less likely to develop in very preterm (RR = 0.67; 95% CI, 0.53-0.84) and postterm (RR = 0.87; 95% CI, 0.83-0.9) infants and more likely to develop in those who were preterm (RR = 1.18; 95% CI, 1.09-1.28) and early term (RR = 1.12; 95% CI, 1.07-1.17) compared with infants born at term. During the sibling study, all associations remained.
The risk for type 1 diabetes was significantly associated with small for gestational age (RR = 0.83; 95% CI, 0.75-0.93) and large for gestational age (RR = 1.14; 95% CI, 1.04-1.23); the association remained during the sibling analysis for small for gestational age, but not for large for gestational age.
Compared with normal birth weight infants, very low birth weight infants (< 1,500 g) were at a lower risk for type 1 diabetes (RR = 0.66; 95% CI, 0.48-0.91); this remained significant during the sibling analysis (RR = 0.5; 95% CI, 0.31-0.8).
“We found that preterm and early-term babies are at increased risk of type 1 diabetes, while very preterm birth, very low birth weight, and [small for gestational age] babies are at reduced risk of type 1 diabetes,” the researchers wrote. “The sibling study suggested that these associations, although small, were not due to familial factors shared by siblings. Further research is warranted to replicate these findings and understand the potential biological mechanisms.” – by Amber Cox
Disclosure: The researchers report no relevant financial disclosures.