The role of very low birth weight and prematurity on cardiovascular disease risk and on kidney development in children: a pilot study.

BACKGROUND

Cardiovascular and renal disease are nowadays among the leading cause of morbidity and mortality in Western Countries. Low birth weight has been recently considered a key factor in determining cardiovascular disease and long-term renal disease in adulthood.

METHODS

In our study we analyzed, through echocardiography, eco color Doppler of carotid arteries, ultrasound of abdominal aorta and kidneys, morphological characteristics of cardiovascular and renal system, in a group of children born preterm with very low birth weight, (birth weight<1500 grams) and in a group of children, age and sex matched, born at term with weight appropriate for gestational age. Fifteen children born very low birth weight preterm (cases), aged from 3 to 5 years, and 15, age and sex matched children, born appropriate for gestational age at term (controls) were enrolled in the study.

RESULTS

The two groups were homogeneous for interventricular septum diameter, left ventricular end-systolic diameter, left atrial diameter, and ejection fraction. Left ventricular end diastolic diameter was higher in case compared to controls (P=0.04), while aortic diameter root smaller (P=0.005). E and A waves peak velocities and E/A ratio resulted lower in cases compared to controls (P=0.02, P<0.001and P<0.001, respectively). Tei index, S, e' and a' waves velocities were similar in the two groups, while E/e' ratio was higher in cases (P=0.046). Intima-media thickness and antero-posterior diameter of abdominal aorta values did not differ in cases versus controls. Longitudinal diameters of both kidneys were reduced in cases compared to controls (P<0.05).

CONCLUSIONS

Although limited by the small sample size, our study highlighted an increased size of the left ventricle and altered left ventricular diastolic function in children born very low birth weight preterm, but no long-term consequences on systolic performance and vascular structure have been found. The finding of smaller kidneys in ex-preterm very low birth weight children could explain their higher susceptibility to develop renal disease in adulthood.