Early versus Late Ventricular Intervention Study (ELVIS) in post-hemorrhagic ventricular dilatation: Bayesian
Mehmet N Cizmeci1, Linda S de Vries2,3, Andrew Whitelaw4
1Division of Neonatology, The Hospital for Sick Children, and Department of Paediatrics, University of Toronto, Toronto, Canada. mehmet.cizmeci@sickkids.ca.
Insights
Early intervention for post-hemorrhagic ventricular dilatation (PHVD) in preterm infants significantly reduces the risk of death or neurodevelopmental impairment. This study shows that delaying treatment increases harm, highlighting early intervention as a key strategy.
Area of Science:
- Neonatal Neurology
- Pediatric Neuroimaging
- Bayesian Statistics in Clinical Research
Background:
- Post-hemorrhagic ventricular dilatation (PHVD) is a significant concern in preterm infants.
- Assessing the optimal timing for intervention in PHVD is crucial for improving outcomes.
Purpose of the Study:
- To evaluate the probability of benefit versus harm associated with early versus late intervention for PHVD.
- To determine the impact of intervention timing on neurodevelopmental impairment (NDI) and death at 2 years.
Main Methods:
- Bayesian logistic regression analysis of data from 126 preterm infants with progressive PHVD.
- Randomization to early (VI >97th percentile) or late (VI >97th percentile +4mm) intervention thresholds.
- Testing four prior distributions to generate posterior estimates for adverse outcomes.
Main Results:
- Early intervention correlated with smaller ventricles and lower global brain injury scores on MRI.
- Late intervention was associated with increased odds of death or NDI (OR 1.56-2.42).
- A 16% absolute risk reduction in adverse outcomes with early intervention (NNT=7).
Conclusions:
- Early cranial ultrasound-guided intervention for PHVD significantly improves neuroimaging and neurodevelopmental outcomes.
- Delaying intervention for PHVD increases the risk of death or moderate to severe NDI.
- Early intervention is a modifiable strategy to improve long-term outcomes in preterm infants with PHVD.
Background:
To assess the probability of benefit and harm with early versus late intervention for post-hemorrhagic ventricular dilatation (PHVD).
Methods:
Bayesian logistic regression analysis was conducted using data from 126 preterm infants (64 Early; 62 Late) with progressive PHVD randomized to early (ventricular indices, VI >97th percentile) or late (VI >97th percentile +4 mm) intervention thresholds. Four potential prior distributions were tested: optimistic, skeptical, neutral, and informative. Posterior estimates were generated for secondary brain injury, and death or neurodevelopmental impairment (NDI) at 2 years.
Results:
Early intervention was associated with smaller ventricles and lower global brain injury scores on term-equivalent age MRI. Across all priors, late intervention was associated with higher odds of adverse outcomes of death or NDI. Posterior odds ratios (OR) for late versus early treatment ranged from 1.56 to 2.42, corresponding to a 91.1-99.7% posterior probability of harm. Under a neutral prior, the estimated OR was 2.09 (95% credible interval 1.01-4.40). The absolute risk difference in the 2-year outcome between groups was 16%, corresponding to a number needed to treat of 7.
Conclusion:
Early, cUS-based intervention for progressive PHVD confers a high probability of improved neuroimaging and neurodevelopmental outcomes at 2 years compared with later intervention.
Clinical Trial Registration Number:
ISRCTN43171322.
Impact:
Bayesian reanalysis of the randomized ELVIS (Early versus Late Ventricular Intervention Study) trial demonstrates a high probability (>90%) that delaying intervention for progressive post-hemorrhagic ventricular dilatation (PHVD) increases the risk of death or moderate to severe neurodevelopmental impairment at 2 years. Early cranial ultrasound-guided intervention was associated with smaller ventricular size and significantly lower global brain injury scores on term-equivalent age MRI, supporting a reduction in secondary brain injury. The absolute risk reduction of 16% translates to a number needed to treat of 7, providing clinically interpretable evidence that earlier intervention is a modifiable strategy to improve neurodevelopmental outcomes in preterm infants with progressive PHVD.