[Metabolic Bone Disease of Prematurity in Very Low Birthweight Infants: Retrospective Observational Study]

Establishment of a nomogram model for predicting metabolic bone disease in preterm infants: A case‒control study

OBJECTIVE

To investigate risk factors for metabolic bone disease (MBD) in preterm infants and establish a nomogram model for predicting MBD risk.

METHODS

A total of 1104 preterm infants were enrolled, among whom 809 were included in the modelling set and 295 were included in the validation set. The modelling set was divided into MBD (n = 185) and non-MBD (n = 624) groups. A multivariate logistic regression analysis was used to investigate the independent risk factors for MBD. R software was used to plot the nomogram model, which was then validated by the data of the validation set. Receiver operating characteristic (ROC) and calibration curves were used to evaluate the nomogram model's performance, and the clinical decision curve was used to assess the clinical practicability of the model.

RESULTS

Gestational age, time of trophic feeding initiation, parenteral nutrition duration, necrotizing enterocolitis, bronchopulmonary dysplasia, cholestasis and sepsis were independent risk factors for MBD in preterm infants (P < 0.05). The ROC curve of the modelling set had an area under the curve (AUC) of 0.801; the risk prediction value of 0.196 corresponding to the maximum Youden index was the best value, and the prediction critical value was 125 points. The ROC curve of the validation set had an AUC of 0.854. The calibration curve analysis showed good accuracy and consistency between the model's predicted and actual values.

CONCLUSIONS

The nomogram model provides an efficient tool for the early assessment of MBD risk. Preterm infants with scores ≥ 125 should receive close attention and interventions in the early stage.

WHAT IS KNOWN

• The incidence and severity of MBD are inversely proportional to gestational age and birth weight. Bone loss can lead to prolonged hospital stay, ventilator dependence, pathological fractures and short stature.

WHAT IS NEW

• Gestational age, time of trophic feeding initiation, parenteral nutrition duration, necrotizing enterocolitis, bronchopulmonary dysplasia, cholestasis and sepsis were independent risk factors for MBD in preterm infants. The nomogram model provides an efficient tool for the early assessment of MBD risk.

Osteopenia of prematurity and associated nutritional factors: case-control study

BACKGROUND

Preterm newborn nutrition affects postnatal skeletal growth and bone mineralization, but studies have not yet fully concluded the relationship between nutrition and osteopenia. This study was intended to investigate the impact of nutritional factors on osteopenia in preterm newborns.

METHODS

This is a case-control study with babies born with gestational age ≤ 32 weeks in a high-risk maternity hospital, between 2018 and 2019. The population consisted of 115 newborns, being 46 cases (40%) and 69 controls (60%). Disease outcome was based on serum alkaline phosphatase levels > 900UL/l and hypophosphatemia < 4 mg/dl. Gestational data at birth and clinical and nutritional follow-up data during 8 weeks postnatally were assessed. Variables were assessed using regressive logistic models.

FINDINGS

Preterm infants who were fed pasteurized fresh human milk with acidity ≥ 4 ºDornic are 5.36 times more likely to develop osteopenia (p = 0.035). Higher calcium intake, compared to controls, also increased the probability of disease occurrence [OR 1.05 (CI 1.006-1.1); p = 0.025], while the presence of a partner [OR 0.10 (CI 0.02-0.59); p = 0.038] and the shortest time using sedatives [OR 0.89 (CI 0.83-0.98); p = 0.010] were protective factors associated with osteopenia. Extremely low birth weight [OR 5.49 (CI 1.20-25.1); p = 0.028], sepsis [OR 5.71 (CI 1.35-24.2); p = 0.018] and invasive ventilatory support [OR 1.09 (CI 1.03-1.18); p = 0.007] were risk factors.

CONCLUSIONS

Acidity and high calcium intake are the main nutritional factors associated with osteopenia of prematurity. Further studies on the use of human milk with lower acidity, recommendation and nutritional supplementation of calcium should be accomplished to guide prevention strategies in newborns at risk for osteopenia during hospital stay.

Risk factors for metabolic bone disease among preterm infants less than 32 weeks gestation with Bronchopulmonary dysplasia

Background

Bronchopulmonary dysplasia (BPD) infants present an increased incidence of metabolic bone disease (MBD), but it is unknown which factors contribute to this. The aim of this study was to determine the risk factors for developing MBD in BPD infants.

Methods

A retrospective review of the medical records of BPD infants admitted to the Neonatal intensive care unit at Zhangzhou Hospital between Jun 2016 and May 2020 was performed. BPD infants with MBD were identified, two contemporaneous without MBD matched by gestational age and gender were randomly selected as controls for each case of MBD. The association between putative risk factors and MBD was estimated with ORs and 95% CIs. A P-value threshold ≤0.2 was used in univariate analysis for inclusion into a multivariate (adjusted) model with a P-value of < 0.05 as statistically significant.

Results

A total of 156 BPD infants were enrolled with 52 cases of MBD and 104 controls. Fetal growth restriction (OR 6.00, 95% CI, 1.81–19.84), extremely low birth weight (OR 3.10, 95% CI, 1.07–8.94), feeding volume < 80 mL/kg/d at the end of the 4th week after birth (OR 14.98, 95% CI, 4.04–55.58), cholestasis (OR 4.44, 95% CI, 1.59–12.40), late onset sepsis (OR 3.95, 95% CI, 1.12–13.98) and prolonged (> 2 weeks) diuretics application (OR 5.45, 95% CI, 1.25–23.84) were found to be statistically significant risk factors for MBD in BPD infants.

Conclusion

In BPD infants of homogeneous gestational age, fetal growth restriction, extremely low birth weight, feeding volume < 80 mL/kg/d at the end of the 4th week after birth, cholestasis and late onset sepsis are significant risk factors for MBD. These findings provide potential predictive factors for MBD in BPD infants and warrant prospective validation.