Women with high levels of the liver enzyme gamma-glutamyl transferase before pregnancy may be more likely to develop gestational diabetes than those with lower levels, according to research published in Diabetes Care.
In a nested case-control study, Sneha B. Sridhar, MPH, of the division of research at Kaiser Permanente Northern California in Oakland, and colleagues compared medical records of 256 women who developed gestational diabetes with 497 women who did not develop gestational diabetes.
“A few studies have looked at liver enzyme levels during pregnancy and the risk of gestational diabetes,” Sridhar said in a press release. “But, to our knowledge, this is the first to look at liver enzyme levels measured before pregnancy.”
All of the women had participated in the Kaiser Permanente Northern California multiphasic health checkup (1984-1996) and had a subsequent pregnancy (1984-2009). Control participants were selected and matched based on year of blood draw (±3 months), age at examination (±2 years), number of intervening pregnancies (0, 1, ≥2) and age at delivery of index pregnancy (±2 years).
The highest quartile vs. the lowest quartile of gamma-glutamyl transferase (GGT) was associated with a twofold increased risk for subsequent gestational diabetes (OR=1.97; 95% CI, 1.14-3.42), after adjusting for race/ethnicity, pre-pregnancy BMI, family history of diabetes and alcohol use. When adjusted for homeostasis model assessment of insulin resistance (HOMA-IR), fasting status and rate of gestational weight gain, the results were diminished.
“The association appeared to be moderated by increased insulin resistance, and in the stratified analysis, it was present only among women who were in the top tertile of HOMA-IR before pregnancy,” the researchers wrote.
No associations were found with two other commonly monitored liver enzymes, alanine aminotransferase and aspartate aminotransferase.
The researchers suggest a risk model to monitor GGT levels before pregnancy could identify women who might benefit from interventions even before conceiving.
Disclosure: The study was supported by grants from the NIH and Eunice Kennedy Shriver National Institute of Child Health and Human Development.