111,112 A positive correlation was found,
however, between birth weight and creatinine-based GFR in a cohort of young adults, born very premature.80 Using 24-hour urine creatinine clearance within adult twin pairs, GFRs were found to be lower in the LBW twin, again suggesting an independent effect of the intrauterine environment on programming of renal function.113 A small cross-sectional study compared total GFR, effective renal plasma flow, and filtration fraction before and after renal stimulation with low-dose Inhibitors,research,lifescience,medical dopamine infusion and oral amino acid intake in 20-year-olds born premature and AGA, premature and SGA, or term and AGA.114 It would be expected that a kidney with fewer nephrons is already hyperfiltering to some degree, which may abrogate any change in serum creatinine, but would have a blunted increase in GFR when stimulated further. This study was limited
Inhibitors,research,lifescience,medical by small sample size, but the relative increase in GFR tended to be lower in SGA compared with AGA and control subjects, and effective renal plasma flow was lower in both SGA and AGA preterm individuals, although not statistically significant.115 A recent study of non-diabetic young adults found a significant reduction in renal functional reserve in those with Inhibitors,research,lifescience,medical diabetic mothers (i.e. exposed to diabetic milieu in utero), compared to those Inhibitors,research,lifescience,medical with diabetic fathers, thereby excluding a genetic confounder, and strongly suggesting a long-term impact of gestational diabetes exposure.114 The authors postulate that reduced renal functional reserve may reflect a programmed reduction in nephron number in Epigenetics inhibitor offspring of diabetic mothers. Evaluation of renal functional reserve may therefore be a more sensitive method to detect subtle changes in renal function due to reduced nephron number. Chronic Kidney Disease A recent meta-analysis of 31 studies found a 70% increase in relative risk of chronic kidney disease (CKD) with LBW.116 A U-shaped curve Inhibitors,research,lifescience,medical for risk of CKD and birth weight (< 2.5 kg or ≥ 4.5 kg) among adult men, but not women,
was found in a large US cohort.117 Many animal studies of fetal programming also report increased out susceptibility to hypertension and renal dysfunction in males, although the reasons for the gender differences are not entirely clear.118 A retrospective study of over 2 million Norwegians reported a relative risk of end-stage renal disease (ESRD) of 1.7 in males and females born below the 10th percentile in weight, but only in females with birth weights > 4.5 kg.119 A U-shaped curve was also described between birth weight and ESRD in both males and females in a predominantly black US population.120 Epidemiologic studies therefore support the relationship between high or low birth weights and risk of CKD.