Identification of practices and morbidities affecting the mortality of very low birth weight infants using a multilevel logistic analysis: clinical trial or standardisation?

Factors associated with the development of epilepsy in very low birth weight infants

BACKGROUND

The survival rate of very low birth weight (VLBW) infants has recently improved. However, the occurrence of and factors associated with epilepsy in VLBW infants remain unknown. This study aimed to clarify the incidence, characteristics, and factors associated with epilepsy development in VLBW infants.

METHODS

All VLBW infants admitted to our hospital between 2012 and 2017 were included in this study. VLBW infants with a follow-up period of <1 year were excluded. Chromosomal abnormalities, brain anomalies, severe intraventricular hemorrhage (IVH), cystic periventricular leukomalacia (PVL), and hypoxic ischemic encephalopathy (HIE) were considered to be risk factors.

RESULTS

Epilepsy occurred in 21/526 (4.0%) VLBW infants. Chromosomal abnormalities, brain anomalies, severe IVH, cystic PVL, HIE, neonatal seizures, advanced maternal age, maternal diabetes mellitus, no administration of antenatal corticosteroids, and low Apgar scores at 1 and 5 min were associated with a risk of epilepsy. The median time to epilepsy onset was 8 months (range: 0-59 months), and the onset occurred within 2 years in 15/21 patients (71.4%) and within 4 years in 18/21 patients (85.7%). VLBW infants with risk factors developed epilepsy earlier and at a significantly higher rate than those without risk factors. Among infants who had risk factors and who developed epilepsy, 86.7% did so within 2 years of age, compared to 33.3% of those who developed epilepsy but did not have risk factors.

CONCLUSION

These findings regarding factors associated with a risk of development of epilepsy and temporal feature of epilepsy may contribute to the development of monitoring and treatment protocols for epilepsy in VLBW infants.

Risk factor analyses for intraventricular hemorrhage in preterm infants: A retrospective cohort study

BACKGROUND

Very-low-birthweight (VLBW) infants can experience severe intraventricular hemorrhage (IVH) that can lead to life-long disability by impairing neurodevelopment. The aim of this study was to identify the risk and protective factors for severe IVH in VLBW infants.

METHODS

A retrospective, cross-sectional review of VLBW infants born at 22-28 weeks' gestation between January 2003 and December 2012 and listed in the Database of Neonatal Research Network in Japan was performed using a statistical model incorporating an odds ratio (OR) and medical center variation as a center variance ratio (CVR). A two-dimensional analysis using a combination of OR and the CVR described evolving measures of a clinical trial (for OR > 1) and standardization (for CVR > 1) concerning a factor of interest.

RESULTS

The noteworthy significant protective factors were antenatal steroids (ANS) with and without premature rupture of membrane (OR: 0.43, CVR: 1.08, and OR: 0.68, CVR: 1.14, respectively) and the number of neonatal beds (OR: 0.94, CVR: 0.99) and staff nurses per neonatal bed (OR: 0.89, CVR: 0.99).

CONCLUSIONS

Active promotion of ANS administration and consolidation of perinatal medical centers can mitigate the development of severe IVH in VLBW infants.

Association of Center-Specific Patient Volumes and Early Respiratory Management Practices with Death and Bronchopulmonary Dysplasia in Preterm Infants

OBJECTIVES

To describe variability in admission volumes and approach to early respiratory support between neonatal intensive care units in the Australian and New Zealand Neonatal Network and to evaluate whether these center-specific factors are associated with death and bronchopulmonary dysplasia.

STUDY DESIGN

This retrospective cohort study included 19 099 neonates born between 25 and 32 weeks' gestation and admitted to 1 of 25 NICUs from 2007 to 2013. Center-specific factors evaluated were annual admission volume and rate of using continuous positive airway pressure (CPAP) rather than intubation as the first mode of respiratory support. Logistic regression was used to examine any association of these center-specific factors with death, BPD, and death or survival with BPD (death/BPD). Analysis was performed separately for 2 gestation groups (25-28 weeks and 29-32 weeks inclusive).

RESULTS

Admission volumes and rates of early CPAP use varied widely across centers. Higher admission volumes were associated with lower odds of death or survival with BPD in the 25-28 week group (aOR 0.93, 99% CI 0.88-0.99 per increase of 10 babies per center annually). Centers with higher early CPAP use did not have lower odds of death or BPD than centers that intubated more frequently.

CONCLUSIONS

Higher admission volumes are associated with more favorable outcomes for the more preterm infants in the Australian and New Zealand Neonatal Network. Further investigation is required to explore why the individual benefits of early CPAP do not translate to better outcomes for centers that use this approach most frequently.

Association of perinatal factors of epilepsy in very low birth weight infants, using a nationwide database in Japan

OBJECTIVE

To determine clinical features of very low birth weight infants (VLBWIs) who had developed epilepsy by age 3 years.

STUDY DESIGN

Multicenter cohort study using the Neonatal Research Network of Japan database. We analyzed clinical variables of 8431 VLBWIs who had recorded data of neurological sequelae at age 3 years. Logistic regression identified the association between variables and development of epilepsy.

RESULT

One hundred and forty-three (1.7%) infants developed epilepsy, 683 (8.1%) showed cerebral palsy (CP), and 1114 (13.2%) had psychomotor delay. Epilepsy was associated with history of sepsis [adjusted odds ratio (AOR) 3.23], severe intraventricular hemorrhage (IVH; AOR 5.13), and cystic periventricular leukomalacia (PVL; AOR 12.7). Severe IVH and cystic PVL were also frequently associated with CP and psychomotor delay.

CONCLUSION

Severe IVH and cystic PVL are strongly associated with development of epilepsy, as well as other neurological sequelae, and are potential critical therapeutic targets.

Volume, size, professionals' specialization and nutrition management of NICUs and their association with treatment quality in VLBW infants

OBJECTIVE

To assess the association of volume, size, the availability of highly-specialized professionals and nutrition management of NICUs with treatment quality among VLBW infants.

STUDY DESIGN

A prospective multicenter study of 923 VLBW infants in 66 German NICUs, born between May and October 2013. Using multilevel modeling, we examined the association between the aforementioned organizational characteristics and treatment quality, measured via major morbidities (severe IVH, PVL, BPD, NEC, FIP, ROP, and discharge without severe complications) and medical process measures of VLBW infants.

RESULTS

After risk-adjustment and accounting for other NICU characteristics, infants in low-volume NICUs were at higher risk of IVH, ROP and PVL. However, the initial effect of volume on process measures (growth velocity, administration of antenatal steroids) disappeared.

CONCLUSION

Volume can only partially explain differences in the treatment quality of VLBWs. The underlying organizational mechanisms should be considered to improve the quality of care.