Correlation of Intelligence Quotient (IQ) of Children Younger than 12 Years Old with History of Preterm Birth

Abstract

Introduction: Intelligence is the ability of using the different powers and effective behaviors or adapting to new situations or diagnosing conditions and qualities of the environment. It seems that a considerable damage to the brain as a result of premature birth in the last weeks of pregnancy in the maturational - structuring process of the brain can be correlated with Intelligent Quotient (IQ). Due to the high incidence of preterm birth and its associated disorders and its impact on the society and according to a few studies in this field, this study was conducted with the aim of determining the association between IQ and preterm birth.Materials and Methods: This cohort study was performed on 303 children of school age. All subjects randomly allocated to cohort groups (n=147) or controls (n=156) with or without any history of preterm birth, respectively. In this study, in addition to demographic characteristics such as age, sex, gestational age at the delivery and parents’ educational levels, the standard Raven test was used by trained interviewers to measure the IQ in children. Then data were analyzed by Statistical software SPSS version 16.0 by central statistical indicators of independent T tests and Chi-square test. Significant difference was set at P<0.05.Results: The mean IQ of the children in the study, obtained the score of 99.75±9.26 regarding which the independent T-test results showed no significant difference between two groups. In this study, no significant relationship was found between age and gestational age and IQ (P=0.499 and P=0.255, respectively). But this study showed a significant positive correlation between IQ and weight and head circumference at birth (r=0.179, P=0.002 and r=0.299, P=<0.001, respectively).Conclusion: Unlike results of a few previous studies on this issue, no significant differences were found between the two groups. It is recommended that future studies to be done on broader populations, and behavioral and psychological dimensions should be considered.

Intelligence Quotient (IQ) in school-aged preterm infants: A systematic review

“…Authors also investigated the relationship between weight at birth and cognition. Some of them found a positive relationship, that is, they showed that the higher the weight, the better the outcomes (Qasemzadeh et al, 2013 ; Cheong et al, 2017 ), and weight at birth was also considered an important predictor of cognitive development. Tommiska et al ( 2020 ) identified significant differences in the proportion of ELBW children in the normative range (62%) with respect to the control group (100%).…”

“…Higher Perinatal Risk Inventory (PERI) scores were associated with lower IQ scores (Turpin et al, 2019 ), significantly affecting VCI. Moreover, variables such as head circunsference at birth, sepsis, necrotizing enterocolitis, longer duration of antibiotic, treated oersistand ductus arteriosus, laser treatment for retinopathy of prematurity (ROP) or severe ROP, height at discharge from the NICU, bronchopulmonary dysplasia, intraventricular hemorrhage, cystic periventricular leukomalacia, postnatal corticosteroids, surgery in the newborn period and perinatal asphyxia (Qasemzadeh et al, 2013 ; Koç et al, 2015 ; Cheong et al, 2017 ; Nagy et al, 2019 ; Kaul et al, 2021b ; Kim et al, 2021 ) correlated significantly and negatively with IQ scores. Another example would be the study of Nagy et al ( 2019 ), where children with BPD obtained lower scores.…”

“…Studies found that GA was positively related to IQ scores (Hutchinson et al, 2013;Joseph et al, 2016;Cheong et al, 2017;Heeren et al, 2017;Domellöf et al, 2020;Kaul et al, 2021b;Carmo et al, 2022) and could be an important predictor of cognitive functioning in school age (Domellöf et al, 2020;van Veen et al, 2020). Other authors, although in lower proportion, did not observe significant relationships between GA and IQ (Fan et al, 2013;Qasemzadeh et al, 2013;Roberts et al, 2013;Koç et al, 2015;Nagy et al, 2019;Kim et al, 2021).…”

“…Authors also investigated the relationship between weight at birth and cognition. Some of them found a positive relationship, that is, they showed that the higher the weight, the better the outcomes (Qasemzadeh et al, 2013;Cheong et al, 2017), and weight at birth was also considered an important predictor 2021) observed that the children who obtained IQ scores <85 were significantly smaller for their GA or significantly lighter at birth or upon discharge from the NICU. Sripada et al…”

RANK/RANKL/OPG axis genes relation to cognitive impairment in children with transfusion-dependent thalassemia: a cross-sectional study

“…They attributed that to little caring about the quality of education of those children [ 24 , 31 ]. The contradictory results can be explained by using different assessment tools, and the extent to which the illness had affected the body and how these patients are supported may differ among different study groups [ 32 , 33 ].…”