The risk of microalbuminuria in the early postpartum years appears to be increased by current glucose intolerance, not prior gestational diabetes, according to recent findings.
In the prospective, observational cohort study, Ravi Retnakaran, MD, MSc, FRCP, of Mount Sinai Hospital in Toronto, and colleagues evaluated 320 pregnant women who were screened for gestational diabetes at 24 to 28 weeks gestation by 50-mg glucose challenge test, as well as an oral glucose tolerance test (OGTT).
This testing revealed that there were 72 participants with normal glucose challenge test and normal glucose tolerance, 90 with abnormal glucose challenge test with normal glucose tolerance, 58 with gestational impaired glucose tolerance and 100 with gestational diabetes.
Participants returned for follow-up at 3 years postpartum, at which time they underwent 2-hour 75-g OGTT. At this visit, fasting spot urine samples were also taken to assess urine microalbumin and creatinine. The researchers found that 80.3% of participants had normal glucose tolerance whereas 19.7% had glucose intolerance. The glucose intolerance in the majority of these cases was prediabetes (85.7%).
The researchers found that at the 3-year postpartum visit, there was no difference in urine microalbumin and creatinine ratio among the four categories of glucose tolerance (P = .23). Moreover, logistic regression analysis revealed that after adjusting for age, ethnicity, family history of diabetes, BMI, blood pressure, estimated glomerular filtration rate and current glucose tolerance, gestational diabetes was not an independent predictor of elevated microalbumin to creatinine 1.5 g/mol or more (OR = 0.43; 95% CI, 0.17-1.11). Conversely, current glucose intolerance was found to be an independent predictor of urine microalbumin to creatinine 1.5 g/mol or more (OR = 3.4; 95% CI, 1.4-8.2).
“In summary, current glucose intolerance, rather than previous [gestational diabetes], is associated with an increased risk of microalbuminuria in the early postpartum years,” the researchers wrote.
According to the researchers, these findings suggest that coexisting prediabetes or diabetes is likely a factor in the increased risk of microalbuminuria that has been observed in women with a history of [gestational diabetes].
“As such, microalbuminuria may provide an early indicator of metabolic deterioration that could facilitate clinical surveillance in this high-risk patient population,” the researchers wrote. “Further longitudinal study is warranted to elucidate the natural history of microalbuminuria and renal function in this population.” – by Jennifer Byrne
Disclosure: The researchers report no relevant financial disclosures.