[Value of different calculation methods for weight growth velocity in predicting long-term neurological and physical development outcomes in preterm infants].

Objectives: To investigate the value of weight growth velocity, calculated using the Patel exponential model and the Z-score change method, in predicting the neurological and physical development outcomes of preterm infants with a gestational age of <30 weeks in the long term.

Methods: A retrospective study was conducted involving preterm infants with a gestational age of <30 weeks who were hospitalized and treated in the Department of Neonatology at Tongji Hospital, Huazhong University of Science and Technology, from January 2017 to June 2022, and were followed up at the outpatient service more than 18 months of age. The preterm infants were divided into high and low rate groups based on the two calculation methods, and the two methods were compared regarding their predictive value for neurological and physical development outcomes in the long term.

Results: The average age of the last follow-up was (23.0±3.6) months. For neurological development, according to the Patel exponential model, the low rate group exhibited a significantly higher abnormal rate in the fine motor domain compared to the high rate group (P<0.05). Using the Z-score change method, the low rate group had significantly higher abnormal rates in both gross motor and fine motor domains, and significantly lower developmental quotients for gross motor, fine motor, and adaptive behavior domains compared to the high rate group (P<0.05). For physical development, there were no significant differences in body length, body weight, head circumference, or the incidence rate of growth restriction between the low rate and high rate groups identified by either method (P>0.05).

Conclusions: Weight growth velocity calculated using the Z-score change method is more effective in predicting long-term neurological outcomes in preterm infants, while weight growth velocity derived from both methods shows no significant association with long-term physical development outcomes.