Preterm birth may increase risk for diabetes

A recent study found the lower the gestational age at birth, the more elevated plasma insulin levels are, not only at birth but in early childhood, too. The finding suggests that preterm birth may be a risk factor for type 2 diabetes mellitus.

A multidisciplinary team of researchers from Johns Hopkins University Bloomberg School of Public Health and School of Medicine and Boston University Medical Center prospectively studied a predominantly urban minority birth cohort of 1,358 children from birth into early childhood. They divided the children into 4 groups: those born at or beyond 39 weeks gestation (ie, full term); those born at 37 to 38 weeks’ gestation (ie, early term); those born at 34 to 36 weeks’ gestation (ie, late preterm); and those born before 34 weeks (ie, early preterm). They measured plasma insulin levels at birth using cord blood and venous blood in early childhood.

The investigators found that plasma insulin levels were inversely associated with gestational age at birth and in early childhood. Average insulin levels at birth were 9.2 µIU/mL for full-term babies; 10.3 µIU/mL for the early term group; 13.2 µIU/mL for the late preterm group; and 18.9 µIU/mL for the early preterm group. Similarly, in early childhood, average insulin levels were 11.2 µIU/mL, 12.4 µIU/mL, 13.3 µIU/mL, and 14.6 µIU/mL, respectively.

Infants who were in the top insulin tertile at birth were more likely to remain there in early childhood compared with the children ranked in the lowest insulin tertile.

An editorial about the study explains that the research coincides with a newfound focus to combat the increasing prevalence of noncommunicable diseases, such as diabetes, by looking at genetic and/or early childhood factors, because waiting until adulthood is often too late to significantly alter outcomes.

According to the March of Dimes, 1 in 9 US babies is born prematurely.

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