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Investigating Relations between the NICU Speech Environment and Weight Gain in Infants Born Very Preterm
Komal Kumar1, Virginia A Marchman2,3, Maya C Morales3
1Division of Neonatal and Developmental Medicine, Department of Pediatrics, Stanford University, Stanford, California.
Insights
Preterm infants in the neonatal intensive care unit (NICU) who heard more speech gained significantly more weight. Speech exposure and caloric intake together explained nearly 60% of weight gain variations in these vulnerable infants.
Area of Science:
- Neonatal intensive care
- Developmental pediatrics
- Speech-language pathology
Background:
- Preterm infants, particularly those born very preterm (<32 weeks gestational age), face risks for poor growth and neurodevelopmental issues.
- The neonatal intensive care unit (NICU) environment, characterized by aversive sounds and limited speech, is implicated in adverse outcomes for preterm infants.
- Previous experimental studies show benefits of direct speech exposure for preterm infants' health factors relevant to neurodevelopment.
Purpose of the Study:
- To investigate the relationship between the NICU speech environment and the rate of weight gain in hospitalized preterm infants.
- To determine if natural variations in NICU speech exposure are associated with short-term health outcomes, specifically physical growth.
Main Methods:
- Study included 20 very preterm infants assessed between 32 and 36 weeks postmenstrual age.
- The speech environment was measured using an automatic speech-counting device.
- Infant weight gain rates and caloric intake were recorded; linear regressions analyzed speech counts and calories as predictors of weight gain.
Main Results:
- Both caloric intake and speech exposure significantly predicted infant weight gain, each explaining approximately 27% of the variance (total R² = 60.2%, p < 0.001).
- Speech counts were not correlated with family visitation, incubator time, or health acuity, suggesting an independent effect.
- Infants with higher speech exposure demonstrated significantly greater weight gain compared to those with lower exposure.
Conclusions:
- Findings suggest that enhancing speech exposure in the NICU may positively influence the physical growth of preterm infants.
- The NICU speech environment appears to play a significant role in the physical health of preterm infants.
- Further research is needed to establish causality and the direction of effects, but NICU care plans should consider increasing speech exposure opportunities.
Objective:
Children born preterm, especially those born very preterm (<32 weeks of gestational age [GA]) are at risk for poor growth and adverse neurodevelopmental outcomes. Adverse growth and neurodevelopmental outcomes in preterm children have been attributed, in part, to the aversive sounds and relative speech paucity of the neonatal intensive care unit (NICU). Experimental studies that directly expose preterm infants to speech sounds in the NICU find significant improvements in health factors relevant to neurodevelopment. Few studies have examined whether natural variations in the speech environment of the NICU are related to short-term health outcomes in preterm infants. Such data are important for optimizing the sound environment of the NICU. Our objective was to examine relations between the NICU speech environment and the rate of weight gain during hospitalization.
Study Design:
Participants were infants born very preterm (n = 20). The speech environment of each infant was assessed at 32 to 36 weeks of postmenstrual age using an automatic speech-counting device. Average rates of weight gain (g/kg/d) were ascertained over the same period. Calories were derived from charted intake (kcals/kg/d). Linear regressions examined caloric intake and speech counts as predictors of infant weight gain.
Results:
Infant weight gain was significantly predicted by caloric intake and speech exposure, each uniquely accounting for approximately 27% variance (total R 2 = 60.2%; p < 0.001). Speech counts were uncorrelated with rates of family visitation, time in incubator, or health acuity.
Conclusion:
While future research should establish causality and direction of effects, enhancing speech exposure in the NICU may be beneficial for physical growth. NICU care plans should consider opportunities to increase speech exposure.
Key Points:
· Preterm infants who experienced greater amounts of speech in the NICU gained significantly more weight than preterm infants who were exposed to lower amounts of speech during the same developmental period (32-36 weeks of postmenstrual age).. · Caloric intake and speech counts accounted for almost 60% of variance in infant weight gain between 32 and 36 weeks of postmenstrual age.. · Speech counts were not significantly correlated with family visitation, how long infants resided in incubators, or health acuity.. · Findings suggest that the NICU speech environment may play an important role in the physical health of preterm infants; however, more studies are needed to determine the directionality of the observed associations..
