Long-term circulatory and renal consequences of intrauterine growth restriction

Using a Very Low Energy Diet to Achieve Substantial Preconception Weight Loss in Women with Obesity: A Review of the Safety and Efficacy

Obesity in women of reproductive age is common. Emerging evidence suggests that maternal obesity not only increases the risk of adverse pregnancy outcomes but also has an enduring impact on the metabolic health of the offspring. Given this, management of obesity prior to pregnancy is critically important. Almost all international guidelines suggest that women with obesity should aim to achieve weight loss prior to pregnancy. However, current pre-conception weight loss therapies are sub-optimal. Lifestyle modification typically results in modest weight loss. This may assist fertility but does not alter pregnancy outcomes. Bariatric surgery results in substantial weight loss, which improves pregnancy outcomes for the mother but may be harmful to the offspring. Alternative approaches to the management of obesity in women planning pregnancy are needed. Very low energy diets (VLEDs) have been proposed as a possible tool to assist women with obesity achieve weight loss prior to conception. While VLEDs can induce substantial and rapid weight loss, there are concerns about the impact of rapid weight loss on maternal nutrition prior to pregnancy and about inadvertent exposure of the early fetus to ketosis. The purpose of this review is to examine the existing literature regarding the safety and efficacy of a preconception VLED program as a tool to achieve substantial weight loss in women with obesity.

Cardiovascular effects of prenatal stress-Are there implications for cerebrovascular, cognitive and mental health outcome?

Prenatal stress programs offspring cognitive and mental health outcome. We reviewed whether prenatal stress also programs cardiovascular dysfunction which potentially modulates cerebrovascular, cognitive and mental health disorders. We focused on maternal stress and prenatal glucocorticoid (GC) exposure which have different programming effects. While maternal stress induced cortisol is mostly inactivated by the placenta, synthetic GCs freely cross the placenta and have different receptor-binding characteristics. Maternal stress, particularly anxiety, but not GC exposure, has adverse effects on maternal-fetal circulation throughout pregnancy, probably by co-activation of the maternal sympathetic nervous system, and by raising fetal catecholamines. Both effects may impair neurodevelopment. Experimental data also suggest that severe maternal stress and GC exposure during early and mid-gestation may increase the risk for cardiovascular disorders. Human data are scarce and especially lacking for older age. Programming mechanisms include aberrations in cardiac and kidney development, and functional changes in the renin-angiotensin-aldosterone-system, stress axis and peripheral and coronary vasculature. Adequate experimental or human studies examining the consequences for cerebrovascular, cognitive and mental disorders are unavailable.

Developmental origins of chronic renal disease: an integrative hypothesis

Cardiovascular diseases are one of the leading causes of mortality. Hypertension (HT) is one of the principal risk factors associated with death. Chronic kidney disease (CKD), which is probably underestimated, increases the risk and the severity of adverse cardiovascular events. It is now recognized that low birth weight is a risk factor for these diseases, and this relationship is amplified by a rapid catch-up growth or overfeeding during infancy or childhood. The pathophysiological and molecular mechanisms involved in the “early programming” of CKD are multiple and partially understood. It has been proposed that the developmental programming of arterial hypertension and chronic kidney disease is related to a reduced nephron endowment. However, this mechanism is still discussed. This review discusses the complex relationship between birth weight and nephron endowment and how early growth and nutrition influence long term HT and CKD. We hypothesize that fetal environment reduces moderately the nephron number which appears insufficient by itself to induce long term diseases. Reduced nephron number constitutes a “factor of vulnerability” when additional factors, in particular a rapid postnatal growth or overfeeding, promote the early onset of diseases through a complex combination of various pathophysiological pathways.

Adverse consequences of accelerated neonatal growth: cardiovascular and renal issues

Epidemiological and experimental studies show that the risk of cardiovascular and metabolic diseases at adulthood is inversely related to the weight at birth. Although with less evidence, low birth weight has been suggested to increase the risk of chronic kidney disease (CKD). It is well established that the developmental programming of arterial hypertension and of renal disease involves in particular renal factors, especially nephron endowment, which is reduced in low birth weight and maternal diabetes situations. Experimental studies, especially in rodents, have demonstrated the long-term influence of postnatal nutrition and/or postnatal growth on cardiovascular, metabolic and renal functions, while human data are scarce on this issue. Vascular and renal diseases appear to have a "multihits" origin, with reduced nephron number the initial hit and rapid postnatal growth the second hit. This review addresses the current understanding of the role of the kidney, both as a mechanism and as a target, in the developmental origins of adult disease theory, with a particular focus on the long-term effects of postnatal growth and nutrition.

The paradox of breastfeeding-associated morbidity among late preterm infants

OBJECTIVE

To synthesize the published research pertaining to breastfeeding establishment and outcomes among late preterm infants and to describe the state of the science on breastfeeding within this population.

DATA SOURCES

Online databases Ovid MEDLINE, CINAHL, PubMed, and reference lists of reviewed articles.

STUDY SELECTION

Nine data-based research articles examining breastfeeding patterns and outcomes among infants born between 34 0/7 and 36 6/7 weeks gestation or overlapping with this time period by at least 2 weeks.

DATA EXTRACTION

Effect sizes and descriptive statistics pertaining to breastfeeding initiation, duration, exclusivity, and health outcomes among late preterm breastfed infants.

DATA SYNTHESIS

Among late preterm mother/infant dyads, breastfeeding initiation appears to be approximately 59% to 70% (U.S.), whereas the odds of breastfeeding beyond 4 weeks or to the recommended 6 months (exclusive breastfeeding) appears to be significantly less than for term infants, and possibly less than infants ≤34 to 35 weeks gestation. Breastfeeding exclusivity is not routinely reported. Rehospitalization, often related to "jaundice" and "poor feeding," is nearly twice as common among late preterm breastfed infants as breastfed term or nonbreastfed late preterm infants. Barriers to optimal breastfeeding in this population are often inferred from research on younger preterm infants, and evidence-based breastfeeding guidelines are lacking.

CONCLUSIONS

Late preterm infants are at greater risk for breastfeeding-associated rehospitalization and poor breastfeeding establishment compared to their term (and possibly early preterm) counterparts. Contributing factors have yet to be investigated systematically.

Renal drug clearance in preterm neonates: relation to prenatal growth

Aminoglycosides and glycopeptides are almost exclusively eliminated by renal excretion. Postmenstrual age (PMA) is the best predictor of their clearance, presumably because it predicts the time course of development of the glomerular filtration rate (GFR). Intrauterine growth restriction has an impact on the normalized weight of the kidney, on the number of nephrons, on GFR, and on tubular function in human perinatal life. We investigated whether prenatal growth also affects clearance of drugs such as aminoglycosides or glycopeptides that are eliminated through the kidney. Observations collected in two population pharmacokinetic studies involving preterm neonates and investigating amikacin and vancomycin in the first month of postnatal life were used to estimate the impact of prenatal growth (as judged by birth weight for gestational age) on the clearance of these drugs. Data from 1212 drug measurements (vancomycin, 648; amikacin, 564) in 531 subjects (vancomycin, 249; amikacin, 282) were available for study. Neonates born small for gestational age (SGA) were found to have a 16.2% (coefficient of variation, 12.2%) reduction in drug clearance. This effect was present from birth up to the postnatal age of 4 weeks. The covariate size (weight 0.75) explained 47.3% of drug clearance; PMA, 25.2%; coadministration of a nonselective cyclo-oxygenase inhibitor, 3.5%; renal function, 7.6%; and SGA, 1.7%. Renal drug clearance is significantly lower in preterm neonates born SGA than in appropriate-for-gestational-age (AGA) controls. This reduced clearance was observed not only at birth but also up to the postnatal age of 4 weeks.