Study of the long term effects of gestational diabetes mellitus and renal function found elevated eGR fund to possibly lead to renal damage.
Chronic kidney disease often progresses to advanced stages when it goes undiagnosed for a long time. This renal damage is usually caused by uncontrolled diabetes, hypertension, dyslipidemia, vascular dysfunction, and other metabolic abnormalities. Gestational diabetes mellitus (GDM) is now being studied to assess the risk of renal damage in these patients postpartum. Although gestational diabetes resolves after birth, these patients are at risk for developing these cardiometabolic abnormalities that can ultimately lead to renal damage. While there is not enough evidence that there is a direct correlation between gestational diabetes mellitus and renal function impairment, it has been investigated whether both GDM alone and GDM followed by subsequent diabetes leads to renal impairment.
In the Diabetes & Women’s Health study, women with GDM who were originally from the Danish National Birth Cohort Study were followed up 9 to 16 years post partum. Of the 91,827 pregnant women in the cohort study, 1,274 women were identified to have GDM. From this group, 607 women underwent a clinical examination where biospecimens were collected and a subset of 361 women were verified to have GDM. Women without GDM were invited to participate in the study for comparison purposes. 619 women provided biospecimens for verification. Blood and urine samples were collected and assayed at the clinical laboratory of Minnesota. Here, urine albumin, urine creatinine, and plasma creatinine were measured. If the urine to albumin to creatinine ratio (UACR) was considered elevated if it was 20 mg/g or more. Glomerular hyperfiltration was defined as an eGFR >95th percentile (116.4 mL/min/1.73m^2). Women with GDM were found to be older and had a history of smoking and drinking alcohol regularly, hypertension, and higher BMIs before their index pregnancy.
During the follow up postpartum, women who had GDM were found to still have higher BMIs and did not exercise at least three days or more each week. Of the women who had GDM, 183 developed diabetes and nine in the non-GDM group developed diabetes. Also, women who had GDM were found to have higher eGFR compared to the women who did not have GDM. This finding was consistent in participants even if they did not develop prediabetes or diabetes postpartum. These women who had GDM also had a higher UACR compared to those women who did not. However, neither GDM nor diabetes alone were found to significantly be associated with UACR. The women excluded in this analysis included women who had type 1 diabetes, preeclampsia or eclampsia, or any type of hypertension during pregnancy.
The finding of elevated eGFRs in women who had GDM could potentially indicate renal damage due to glomerular hyperfiltration. The only renal dysfunction found was in women who had GDM and then developed overt diabetes. This was indicated by an elevated UACR. This study was the first to evaluate long-term renal function in both independent and joint associations of GDM and subsequent diabetes. There were many strengths of this study, including a prospective data collection, a long-term follow up, and a large study population with many GDM cases. GDM was also well-characterized in this study with interviews, registry data, and verified biospecimens.
Limitations of the study included glucose measurements taken by different measures at different times during the pregnancies of the participants. Also, the study population only included women who were non-Hispanic and white, but no other races. Furthermore, renal markers were only assessed after the index pregnancy.
To conclude, gestational diabetes mellitus can easily be considered a risk factor for future renal damage, especially if it progresses to become type 2 diabetes. However, it was discovered that women did not have to develop diabetes post-pregnancy to have higher eGFR’s. Women with a history of GDM are at a high risk of having renal damage along with all other patients who have other cardiometabolic abnormalities.
- Gestational diabetes alone or followed by subsequent diabetes can lead to an increased eGFR.
- Increased eGFR can lead to glomerular hyperfiltration, which can ultimately lead to renal damage.
- Besides GDM, it is important to assess all risk factors that can contribute to long-term renal damage.
Rawal, Shristi, et al. “Gestational Diabetes Mellitus and Renal Function: A Prospective Study With 9- to 16-Year Follow-up After Pregnancy.” Diabetes Care, American Diabetes Association, 1 July 2018, care.diabetesjournals.org/content/41/7/1378.
Amanda Cortes LECOM School of Pharmacy PharmD Candidate C/O 2019