ABSTRACT
OBJECTIVE: This study aimed to look for a possible relationship between thyrotropin (TSH) values from neonatal bloodspot screening testing and newborn lower auditory pathway myelinization evaluated using the brainstem evoked response audiometry (ABR) test. METHODS: Sixty-two healthy full-term newborns without perinatal problems were enrolled in the study. TSH results were collected from neonatal bloodspot screening data and were below the test cut-off level (15µUI/mL). The TSH test was performed between three and seven days, and the ABR test was performed in the first 28 days of life. The newborns were divided into two groups: Group 1 (n = 35), TSH between 0 and 5µUI/mL, and group 2 (n = 27), TSH between 5 and 15µUI/mL. Data are presented as mean ± SD, median, or percentage, depending on the variable. RESULTS: Wave latency and interpeak interval values for Groups 1 and 2 were as follows: Wave I: 1.8 ± 0.1 and 1.7 ± 0.1; Wave III: 4.4 ± 0.1 and 4.4 ± 0.1; Wave V: 6.9 ± 0.1 and 6.9 ± 0.1; interval I-III: 2.6 ± 0.1 and 2.6 ± 0.1; interval I-V: 5.1 ± 0.1 and 5.1 ± 0.1; interval III-V: 2.4 ± 0.1 and 2.4 ± 0.1. There were no significant differences in ABR parameters between groups 1 and 2 (p > 0.05). Multiple regression analysis showed a slight significant negative correlation between TSH and wave I values (standardized ß = -0.267; p = 0.036), without observing any relationship with the other ABR waves recorded. CONCLUSIONS: This study investigated the relationship of TSH and auditory myelinization evaluated by ABR. It did not show a significant change in lower auditory pathway myelinization according to TSH levels in newborns with TSH screening levels lower than 15 µUI/mL.
Subject(s)
Auditory Pathways , Thyrotropin/blood , Adult , Audiometry, Evoked Response , Auditory Pathways/growth & development , Auditory Pathways/physiology , Congenital Hypothyroidism/blood , Congenital Hypothyroidism/physiopathology , Cross-Sectional Studies , Female , Humans , Infant, Newborn , MaleABSTRACT
Abstract Objective: This study analyzed the relationship between latent iron deficiency evaluated by ferritin, and the myelination of the central nervous system evaluated through the brainstem evoked response audiometry test. Method: A total of 109 full-term newborns, born without anemia and risk factor for hearing deficiency, were enrolled. After delivery, umbilical cord blood was collected to determine ferritin and hematocrit levels. The brainstem evoked response audiometry test was carried out in the first 28 days of life. Analysis was performed between the control group (n = 71) with ferritin greater than 75 ng/mL, and the latent iron deficiency group (n = 38) with ferritin between 11 and 75 ng/mL. Results were presented as mean ± standard deviation. Statistical analysis was performed using GraphPad prism7 and SPSS with a significance level of 5%. Results: A significant higher V-wave (p = 0.02) and interpeak intervals I-III (p = 0.014), I-V (p = 0.0003), and III-V (p = 0.0002) latencies were found in the latent iron deficiency group, as well as a significant inversely proportional correlation between ferritin and the same wave and intervals (p = 0.003, p = 0.0013, p = 0.0002, p = 0.009, respectively). Multiple correlation analysis showed a significant correlation of latent iron deficiency with all interpeak intervals, even taking into account newborn gestational age. Conclusion: Iron deficiency anemia is a prevalent pathology; this study showed auditory delayed maturation associated to intrauterine iron deficiency, even in its latent form. This reinforces the importance of adopting effective measures, on a global scale, to prevent and treat this pathology in different life periods, especially in the most vulnerable population.
Resumo Objetivo Este estudo analisou a relação entre deficiência de ferro latente avaliada pela ferritina e a mielinização do sistema nervoso central avaliada pelo teste de Potenciais Evocados Auditivos de Tronco Encefálico. Método Foram incluídos no estudo 109 recém-nascidos a termo, nascidos sem anemia e fator de risco para deficiência auditiva. Após o parto, o sangue do cordão umbilical foi coletado para determinar os níveis de ferritina e hematócrito. O teste de Potenciais Evocados Auditivos de Tronco Encefálico foi realizado nos primeiros 28 dias de vida. A análise foi realizada entre o grupo controle (n = 71) com ferritina acima de 75 ng/mL e o grupo com deficiência de ferro latente (n = 38) com ferritina entre 11 e 75 ng/mL. Os resultados foram apresentados como média ± desvio-padrão. A análise estatística foi realizada utilizando o software GraphPad prism7 e SPSS com nível de significância de 5%. Resultados Latências significativamente maiores da onda V (p = 0,02) e dos intervalos interpicos I-III (p = 0,014), I-V (p = 0,0003) e III-V (p = 0,0002) foram encontradas no grupo de deficiência de ferro latente, assim como uma correlação significativa inversamente proporcional entre a ferritina e a mesma onda e intervalos (p = 0,003, p = 0,0013, p = 0,0002, p = 0,009, respectivamente). A análise de correlação múltipla mostrou uma correlação significativa da deficiência de ferro latente com todos os intervalos interpicos, mesmo se levarmos em consideração a idade gestacional do recém-nascido. Conclusão A anemia ferropriva é uma patologia prevalente e este estudo demonstrou maturação auditiva tardia associada à deficiência intrauterina de ferro, mesmo em sua forma latente. Isso reforça a importância da adoção de medidas efetivas, em escala global, para prevenir e tratar essa patologia em diferentes períodos da vida, principalmente na população mais vulnerável.
Subject(s)
Humans , Infant, Newborn , Anemia, Iron-Deficiency , Evoked Potentials, Auditory, Brain Stem , Gestational Age , Term Birth , Ferritins , Fetal BloodABSTRACT
OBJECTIVE: This study analyzed the relationship between latent iron deficiency evaluated by ferritin, and the myelination of the central nervous system evaluated through the brainstem evoked response audiometry test. METHOD: A total of 109 full-term newborns, born without anemia and risk factor for hearing deficiency, were enrolled. After delivery, umbilical cord blood was collected to determine ferritin and hematocrit levels. The brainstem evoked response audiometry test was carried out in the first 28 days of life. Analysis was performed between the control group (n=71) with ferritin greater than 75ng/mL, and the latent iron deficiency group (n=38) with ferritin between 11 and 75ng/mL. Results were presented as mean±standard deviation. Statistical analysis was performed using GraphPad prism7 and SPSS with a significance level of 5%. RESULTS: A significant higher V-wave (p=0.02) and interpeak intervals I-III (p=0.014), I-V (p=0.0003), and III-V (p=0.0002) latencies were found in the latent iron deficiency group, as well as a significant inversely proportional correlation between ferritin and the same wave and intervals (p=0.003, p=0.0013, p=0.0002, p=0.009, respectively). Multiple correlation analysis showed a significant correlation of latent iron deficiency with all interpeak intervals, even taking into account newborn gestational age. CONCLUSION: Iron deficiency anemia is a prevalent pathology; this study showed auditory delayed maturation associated to intrauterine iron deficiency, even in its latent form. This reinforces the importance of adopting effective measures, on a global scale, to prevent and treat this pathology in different life periods, especially in the most vulnerable population.