Longitudinal neurodevelopmental evolution in children with severe non-progressive encephalopathy

The aim of this study was to evaluate the longitudinal neurodevelopmental evolution in children with severe non-progressive encephalopathy.

Between 1984 and 2005, 17 patients diagnosed with severe non-progressive encephalopathy under the care of the Institute Provvida Madre underwent neurodevelopmental evaluation on an annual basis for at least five consecutive years using the Munich Functional Developmental Diagnostics (MFDD). The severity of each patient's encephalopathy was assessed using the Capacity Profile (CAP). Longitudinal development trends were assessed by means of linear regression analysis, while the degree of discontinuity of the development trajectories was quantified using the Mean Absolute Deviation from Perfect Linear Development (MADPLD). Spearman's rank correlation coefficient and the Mann-Whitney test have been used to investigate the statistical significance of the relationships among the various parameters.

We found that patients with severe non-progressive encephalopathy showed, on average, a linear maturation of 1.5-2.5months per year, irrespective of the neurodevelopmental area considered. Nevertheless, we also discovered that the development trajectories could be discontinuous. Indeed, a given child can show no development sign at all for many years and then suddenly encounter a "development jump", especially in the active language and autonomy areas. However, the long-term development linearity hypothesis seemed to hold true in our study. We also found evidences suggesting that faster development in a given domain could be linked to faster development in other domains, that higher discontinuity in a given area could be associated with higher discontinuity in other areas and that higher degrees of discontinuity could be related to lower developmental evolutions.

The main findings of this study are important for physicians to form prognoses, counsel effectively and appropriately target therapeutic interventions. In this perspective, there is a strong need to collect long-term repeated follow-up data concerning this group of infants in order to reinforce the findings presented. In fact, these results should be considered as a starting point for further research because they are based on a limited number of patients and more data are needed to confirm the findings.