Maternal Diabetes Mellitus and Persistent Pulmonary Hypertension of the Newborn: Accumulated Evidence From Observational Studies

Assessment of Myocardial Function in Infants of Mothers with Gestational Diabetes Mellitus Using Deformation Imaging over the First Year of Age

OBJECTIVE

To assess serial myocardial performance and pulmonary vascular resistance (PVR) in infants of mothers with gestational diabetes mellitus (GDM) over the first year of life.

STUDY DESIGN

This was a prospective, observational study. Echocardiography was performed at birth, 6 months, and 1 year of age. Pulmonary artery acceleration time and left ventricular (LV) eccentricity index provided surrogate measurements of PVR. Biventricular function was assessed by tissue Doppler imaging and deformation analysis.

RESULTS

Fifty infants of mothers with GDM were compared with 50 controls with no difference in gestation (38.9 ± 0.8 weeks vs 39.3 ± 0.9 weeks; P = .05) or birthweight (3.55 ± 0.49 kg vs 3.56 ± 0.41 kg; P = .95). At 1 year of age, the pulmonary artery acceleration time was lower (70 ± 11 vs 79 ± 10; P = .01) in the GDM group. LV global longitudinal strain (24.7 ± 1.9 vs 28.8 ± 1.8 %; P < .01), LV systolic strain rate (1.8 ± 0.2 vs 2.1 ± 0.3 1/s; P < .01), and RV free wall strain (31.1 ± 4.8 vs 34.6 ± 3.9 %; P < .01) were lower in the GDM cohort at 1 year of age (all P values adjusted for gestation, mode of delivery, and maternal body mass index).

CONCLUSIONS

Our findings demonstrate higher indices of PVR and lower biventricular function in infants of mothers with GDM compared with controls at each time point assessed in this study over the first year of life.

Diabetes and anti-diabetic interventions and the risk of gynaecological and obstetric morbidity: an umbrella review of the literature

BACKGROUND

Diabetes has reached epidemic proportions in recent years with serious health ramifications. The aim of this study was to evaluate the strength and validity of associations between diabetes and anti-diabetic interventions and the risk of any type of gynaecological or obstetric conditions.

METHODS

Design: Umbrella review of systematic reviews and meta-analyses.

DATA SOURCES

PubMed, Medline, Embase, Cochrane Database of Systematic Reviews, manual screening of references.

ELIGIBILITY CRITERIA

Systematic reviews and meta-analyses of observational and interventional studies investigating the relationship between diabetes and anti-diabetic interventions with gynaecological or obstetric outcomes. Meta-analyses that did not include complete data from individual studies, such as relative risk, 95% confidence intervals, number of cases/controls, or total population were excluded.

DATA ANALYSIS

The evidence from meta-analyses of observational studies was graded as strong, highly suggestive, suggestive or weak according to criteria comprising the random effects estimate of meta-analyses and their largest study, the number of cases, 95% prediction intervals, I² heterogeneity index between studies, excess significance bias, small study effect and sensitivity analysis using credibility ceilings. Interventional meta-analyses of randomised controlled trials were assessed separately based on the statistical significance of reported associations, the risk of bias and quality of evidence (GRADE) of included meta-analyses.

RESULTS

A total of 117 meta-analyses of observational cohort studies and 200 meta-analyses of randomised clinical trials that evaluated 317 outcomes were included. Strong or highly suggestive evidence only supported a positive association between gestational diabetes and caesarean section, large for gestational age babies, major congenital malformations and heart defects and an inverse relationship between metformin use and ovarian cancer incidence. Only a fifth of the randomised controlled trials investigating the effect of anti-diabetic interventions on women's health reached statistical significance and highlighted metformin as a more effective agent than insulin on risk reduction of adverse obstetric outcomes in both gestational and pre-gestational diabetes.

CONCLUSIONS

Gestational diabetes appears to be strongly associated with a high risk of caesarean section and large for gestational age babies. Weaker associations were demonstrated between diabetes and anti-diabetic interventions with other obstetric and gynaecological outcomes.

TRIAL REGISTRATION

Open Science Framework (OSF) (Registration https://doi.org/10.17605/OSF.IO/9G6AB ).

AMPK deficiency in smooth muscles causes persistent pulmonary hypertension of the new-born and premature death

AMPK has been reported to facilitate hypoxic pulmonary vasoconstriction but, paradoxically, its deficiency precipitates pulmonary hypertension. Here we show that AMPK-α1/α2 deficiency in smooth muscles promotes persistent pulmonary hypertension of the new-born. Accordingly, dual AMPK-α1/α2 deletion in smooth muscles causes premature death of mice after birth, associated with increased muscularisation and remodeling throughout the pulmonary arterial tree, reduced alveolar numbers and alveolar membrane thickening, but with no oedema. Spectral Doppler ultrasound indicates pulmonary hypertension and attenuated hypoxic pulmonary vasoconstriction. Age-dependent right ventricular pressure elevation, dilation and reduced cardiac output was also evident. KV1.5 potassium currents of pulmonary arterial myocytes were markedly smaller under normoxia, which is known to facilitate pulmonary hypertension. Mitochondrial fragmentation and reactive oxygen species accumulation was also evident. Importantly, there was no evidence of systemic vasculopathy or hypertension in these mice. Moreover, hypoxic pulmonary vasoconstriction was attenuated by AMPK-α1 or AMPK-α2 deletion without triggering pulmonary hypertension.

Management of Hypertrophic Cardiomyopathy in a Newborn with Dextro-Transposition of the Great Arteries

Impaired maternal glucose metabolism during pregnancy can have significant effects on the cardiovascular system of the developing fetus. Early in pregnancy the teratogenic effects may lead to structural heart defects, while later in gestation a form of hypertrophic cardiomyopathy can develop due to overgrowth driven by fetal hyperinsulinism. We describe an infant with the uncommon combination of both dextro-transposition of the great arteries and hypertrophic cardiomyopathy. We emphasize the importance of a longitudinal multi-disciplinary approach, from fetal diagnosis to post-operative management, that allowed for an excellent outcome in this rare combination of severe cardiac malformations.