Association of preterm birth and birth size status with neurodevelopmental and psychiatric disorders in spontaneous births.

Preterm birth (PTB) or small birth size are risk factors for certain neurodevelopmental disorders. The magnitude of these associations in spontaneous births, and of associations for combined PTB and birth size status on neurodevelopmental and psychiatric disorders is unexplored. We investigated whether PTB and small/large for gestational age (SGA/LGA), separately or combined, in spontaneous births, are associated with a wide spectrum of neurodevelopmental and psychiatric disorders. In this population-based registry cohort study, all singleton spontaneous births in Finland from 1996 to 2014 were followed until 2018 (n = 819 764). We show that PTB across gestational ages, and SGA, were associated with higher risks for anxiety disorders, intellectual disabilities, specific developmental disorders (SDD), autism spectrum disorders (ASD), attention-deficit/hyperactivity disorders (ADHD) and other emotional and behavioural disorders (F98). Most of these associations were not attributed to familial factors. Larger effect sizes were observed with lower gestational ages. Extremely PTB was associated at highest risks with intellectual disabilities (HR, 10.70 [95%CI, 8.69-13.17]) and SDD (HR, 8.91 [95%CI, 8.18-9.71]). Moreover, very preterm birth combined with SGA was associated with a higher risk for SDD (HR, 7.55 [95%CI, 6.61-8.62]) than that of very preterm or SGA birth alone. Conversely, LGA birth lowered the risk for SDD and other emotional and behavioural disorders among individuals born very preterm. In conclusion, PTB along with SGA is associated with higher risks for SDD than one exposure alone, whereas LGA lowers the risks for SDD and other emotional and behavioural disorders in individuals born spontaneously.

Severity of muscle impairment and its progression assessed using musculoskeletal magnetic resonance imaging and diffusion tension imaging in 78 boys with Duchenne muscular dystrophy: a retrospective study.

Purpose: Duchenne muscular dystrophy (DMD) is the most common and severe form of muscular dystrophy. Current diagnostic tests like genetic testing, needle electromyography, and muscle biopsy are either not easily available or invasive, and they are impractical for assessing disease progression and treatment outcomes. Therefore, there is a need for a non-invasive and accurate investigative modality for DMD. In recent years, musculoskeletal magnetic resonance imaging (MRI-MSK) along with fractional anisotropy (FA) and diffusion tensor imaging (DTI) have become major non-invasive tools. Material and methods: T1-weighted MRI-MSK and FA measures of DTI of 78 DMD patients were retrospectively studied to identify the distinct pattern of muscle involvement and fatty infiltration as age and/or disease progresses. Correlation analysis was performed between MRI-MSK grade score vs. age, muscle strength, and Vignos scale. Spearman's rank correlation coefficient was used. Results: As age increased, the MRI grade score and Vignos score increased. There was a statistically significant high positive correlation between MRI-MSK grade score and age, and low positive correlation with Vignos scores. With increasing age, the muscle strength on manual muscle testing (MMT) and FA value decreased. There was high negative correlation with muscle strength on MMT and low positive correlation between FA values and MMT score. Conclusions: On T1-weighted MRI, a distinct pattern, extent, and distribution of lower limb muscle involvement can be seen. MRI-MSK grade score worsens with progressing age, reducing strength, and increasing functional impairment. FA alone may not be an accurate marker in assessing progression of DMD. MRI-MSK and other DTI measures should be further explored as diagnostic and prognostic tools for DMD.

Neurodevelopmental correlates of caudate volume in children born at risk of neonatal hypoglycaemia.

BACKGROUND: Neonatal hypoglycaemia can lead to brain damage and neurocognitive impairment. Neonatal hypoglycaemia is associated with smaller caudate volume in the mid-childhood. We investigated the relationship between neurodevelopmental outcomes and caudate volume and whether this relationship was influenced by neonatal hypoglycaemia. METHODS: Children born at risk of neonatal hypoglycaemia ≥36 weeks' gestation who participated in a prospective cohort study underwent neurodevelopmental assessment (executive function, academic achievement, and emotional-behavioural regulation) and MRI at age 9-10 years. Neonatal hypoglycaemia was defined as at least one hypoglycaemic episode (blood glucose concentration <2.6 mmol/L or at least 10 min of interstitial glucose concentrations <2.6 mmol/L). Caudate volume was computed using FreeSurfer. RESULTS: There were 101 children with MRI and neurodevelopmental data available, of whom 70 had experienced neonatal hypoglycaemia. Smaller caudate volume was associated with greater parent-reported emotional and behavioural difficulties, and poorer prosocial behaviour. Caudate volume was significantly associated with visual memory only in children who had not experienced neonatal hypoglycaemia (interaction p = 0.03), but there were no other significant interactions between caudate volume and neonatal hypoglycaemia. CONCLUSION: Smaller caudate volume is associated with emotional behaviour difficulties in the mid-childhood. Although neonatal hypoglycaemia is associated with smaller caudate volume, this appears not to contribute to clinically relevant neurodevelopmental deficits. IMPACT: At 9-10 years of age, caudate volume was inversely associated with emotional-behavioural difficulties and positively associated with prosocial behaviour but was not related to executive function or educational achievement. Previous studies have suggested that neonatal hypoglycaemia may contribute to smaller caudate volume but exposure to neonatal hypoglycaemia did not appear to influence the relationship between caudate volume and behaviour. Among children not exposed to neonatal hypoglycaemia, caudate volume was also positively associated with visual memory, but no such association was detected among those exposed to neonatal hypoglycaemia. Understanding early-life factors that affect caudate development may provide targets for improving behavioural function.

Executive function and behaviour problems in school-age children born at risk of neonatal hypoglycaemia.

AIM: To examine the relationship between neonatal hypoglycaemia and specific areas of executive function and behaviour in mid-childhood. METHOD: Participants in a prospective cohort study of infants born late preterm or at term at risk of neonatal hypoglycaemia were assessed at 9 to 10 years. We assessed executive function using performance-based (Cambridge Neuropsychological Tests Automated Battery) and questionnaire-based (Behavior Rating Inventory of Executive Function) measures and behaviour problems with the Strengths and Difficulties Questionnaire. Data are reported as adjusted odds ratio (aOR) with 95% confidence intervals, and standardized regression coefficients. RESULTS: We assessed 480 (230 females, 250 males; mean age 9 years 5 months [SD 4 months, range 8 years 8 months-11 years 0 months]) of 587 eligible children (82%). There were no differences in performance-based executive function between children who did and did not experience neonatal hypoglycaemia (blood glucose <2.6 mmoL/L). However, children who experienced hypoglycaemia, especially if severe or recurrent, were at greater risk of parent-reported metacognition difficulties (aOR 2.37-3.71), parent-reported peer (aOR 1.62-1.89) and teacher-reported conduct (aOR 2.14 for severe hypoglycaemia) problems. Both performance- and questionnaire-based executive functions were associated with behaviour problems. INTERPRETATION: Neonatal hypoglycaemia may be associated with difficulties in specific aspects of parent-reported executive functions and behaviour problems in mid-childhood.

Effects of prenatal exposure to maternal diabetes mellitus on deep grey matter structures and attention deficit hyperactivity disorder symptoms in children.

AIM: The neuronal mechanism linking the association between maternal diabetes mellitus (DM) and risk of attention deficit hyperactivity disorder (ADHD) symptoms and working memory deficits in children was investigated. METHODS: A total of 6291 children (52% boys) born beyond 28 weeks of gestation were included and underwent brain magnetic resonance imaging scans at 9-10 years. Subcortical brain volumes were estimated from the T1-weighted images. ADHD symptoms were assessed using factorial analysis of the Child Behaviour Checklist completed by parents/caregivers. Working memory performance was assessed with the NIH Toolbox. RESULTS: Compared to unexposed children, those exposed to DM (n = 422) had smaller (ß = -0.15, p = 0.001) volumes of pooled deep grey matter (GM). Regional analysis revealed smaller volumes of the caudate nucleus, putamen, thalamus and cerebellum but not of hippocampus. They also had altered cortico-striatal white matter projection tracts. DM was not associated with working memory deficits or inattention, but with increased hyperactivity/impulsivity and Sluggish Cognitive Tempo symptoms in boys. This hyperactivity/impulsivity symptom in boys was partially mediated by smaller deep GM volume. CONCLUSION: Exposure to DM during pregnancy leads to altered deep GM development during late childhood in their offspring. This contributed to an increased risk of hyperactivity/impulsivity symptoms in boys.

Association of Neonatal Hypoglycemia With Academic Performance in Mid-Childhood.

Importance: Neonatal hypoglycemia is associated with increased risk of poor executive and visual-motor function, but implications for later learning are uncertain. Objective: To test the hypothesis that neonatal hypoglycemia is associated with educational performance at age 9 to 10 years. Design, Setting, and Participants: Prospective cohort study of moderate to late preterm and term infants born at risk of hypoglycemia. Blood and masked interstitial sensor glucose concentrations were measured for up to 7 days. Infants with hypoglycemic episodes (blood glucose concentration <47 mg/dL [2.6 mmol/L]) were treated to maintain a blood glucose concentration of at least 47 mg/dL. Six hundred fourteen infants were recruited at Waikato Hospital, Hamilton, New Zealand, in 2006-2010; 480 were assessed at age 9 to 10 years in 2016-2020. Exposures: Hypoglycemia was defined as at least 1 hypoglycemic event, representing the sum of nonconcurrent hypoglycemic and interstitial episodes (sensor glucose concentration <47 mg/dL for ≥10 minutes) more than 20 minutes apart. Main Outcomes and Measures: The primary outcome was low educational achievement, defined as performing below or well below the normative curriculum level in standardized tests of reading comprehension or mathematics. There were 47 secondary outcomes related to executive function, visual-motor function, psychosocial adaptation, and general health. Results: Of 587 eligible children (230 [48%] female), 480 (82%) were assessed at a mean age of 9.4 (SD, 0.3) years. Children who were and were not exposed to neonatal hypoglycemia did not significantly differ on rates of low educational achievement (138/304 [47%] vs 82/176 [48%], respectively; adjusted risk difference, -2% [95% CI, -11% to 8%]; adjusted relative risk, 0.95 [95% CI, 0.78-1.15]). Children who were exposed to neonatal hypoglycemia, compared with those not exposed, were significantly less likely to be rated by teachers as being below or well below the curriculum level for reading (68/281 [24%] vs 49/157 [31%], respectively; adjusted risk difference, -9% [95% CI, -17% to -1%]; adjusted relative risk, 0.72 [95% CI, 0.53-0.99; P = .04]). Groups were not significantly different for other secondary end points. Conclusions and Relevance: Among participants at risk of neonatal hypoglycemia who were screened and treated if needed, exposure to neonatal hypoglycemia compared with no such exposure was not significantly associated with lower educational achievement in mid-childhood.

Long-term impact of digital media on brain development in children.

Digital media (DM) takes an increasingly large part of children's time, yet the long-term effect on brain development remains unclear. We investigated how individual effects of DM use (i.e., using social media, playing video games, or watching television/videos) on the development of the cortex (i.e., global cortical surface area), striatum, and cerebellum in children over 4 years, accounting for both socioeconomic status and genetic predisposition. We used a prospective, multicentre, longitudinal cohort of children from the Adolescent Brain and Cognitive Development Study, aged 9.9 years when entering the study, and who were followed for 4 years. Annually, children reported their DM usage through the Youth Screen Time Survey and underwent brain magnetic resonance imaging scans every 2 years. Quadratic-mixed effect modelling was used to investigate the relationship between individual DM usage and brain development. We found that individual DM usage did not alter the development of cortex or striatum volumes. However, high social media usage was associated with a statistically significant change in the developmental trajectory of cerebellum volumes, and the accumulated effect of high-vs-low social media users on cerebellum volumes over 4 years was only ß = - 0.03, which was considered insignificant. Nevertheless, the developmental trend for heavy social media users was accelerated at later time points. This calls for further studies and longer follow-ups on the impact of social media on brain development.

Abnormal Development of the Corpus Callosum in Autism Spectrum Disorder: An MRI Study.

BACKGROUND: Altered size in the corpus callosum (CC) has been reported in individuals with autism spectrum disorder (ASD), but few studies have investigated younger children. Moreover, knowledge about the age-related changes in CC size in individuals with ASD is limited. OBJECTIVES: Our objective was to investigate the age-related size of the CC and compare them with age-matched healthy controls between the ages of 2 and 18 years. METHODS: Structural-weighted images were acquired in 97 male patients diagnosed with ASD; published data were used for the control group. The CC was segmented into 7 distinct subregions (rostrum, genu, rostral body, anterior midbody, posterior midbody, isthmus, and splenium) as per Witelson's technique using ITK-SNAP software. We calculated both the total length and volume of the CC as well as the length and height of its 7 subregions. The length of the CC measures was studied as both continuous and categorical forms. For the continuous form, Pearson's correlation was used, while categorical forms were based on age ranges reflecting brain expansion during early postnatal years. Differences in CC measures between adjacent age groups in individuals with ASD were assessed using a Student t-test. Mean and standard deviation scores were compared between ASD and control groups using the Welch t-test. RESULTS: Age showed a moderate positive association with the total length of the CC (r = 0.43; Padj = 0.003) among individuals with ASD. Among the subregions, a positive association was observed only in the anterior midbody of the CC (r = 0.41; Padj = 0.01). No association was found between the age and the height of individual subregions or with the total volume of the CC. In comparison with healthy controls, individuals with ASD exhibited shorter lengths and heights of the genu and splenium of the CC across wide age ranges. CONCLUSION: Overall, our results highlight a distinct abnormal developmental trajectory of CC in ASD, particularly in the genu and splenium structures, potentially reflecting underlying pathophysiological mechanisms that warrant further investigation.

The impact of heat treatment of bovine milk on gastric emptying and nutrient appearance in peripheral circulation in healthy females: a randomized controlled trial comparing pasteurized and ultra-high temperature milk.

BACKGROUND: Heat treatments of dairy, including pasteurization and ultra-high temperature (UHT) processing, alter milk macromolecular structures, and ultimately affect digestion. In vitro, animal, and human studies show faster nutrient release or circulating appearance after consuming UHT milk (UHT-M) compared with pasteurized milk (PAST-M), with a faster gastric emptying (GE) rate proposed as a possible mechanism. OBJECTIVES: To investigate the impact of milk heat treatment on GE as a mechanism of faster nutrient appearance in blood. We hypothesized that GE and circulating nutrient delivery following consumption would be faster for UHT-M than PAST-M. METHODS: In this double-blind randomized controlled cross-over trial, healthy female (n = 20; 27.3 ± 1.4 y, mean ± SD) habitual dairy consumers, consumed 500 mL of either homogenized bovine UHT-M or PAST-M (1340 compared with 1320 kJ). Gastric content volume (GCV) emptying half-time (T50) was assessed over 3 h by magnetic resonance imaging subjective digestive symptoms, plasma amino acid, lipid and B vitamin concentrations, and gastric myoelectrical activity were measured over 5 h. RESULTS: Although GCV T50 did not differ (102 ± 7 min compared with 89 ± 8 min, mean ± SEM, UHT-M and PAST-M, respectively; P = 0.051), GCV time to emptying 25% of the volume was 31% longer following UHT-M compared with PAST-M (42 ± 2 compared with 32 ± 4 min, P = 0.004). Although GCV remained larger for a longer duration following UHT-M (treatment × time interaction, P = 0.002), plasma essential amino acid AUC was greater following UHT-M than PAST-M (55,324 ± 3809 compared with 36,598 ± 5673 µmol·min·L-1, P = 0.006). Heat treatment did not impact gastric myoelectrical activity, plasma appetite hormone markers or subjective appetite scores. CONCLUSIONS: Contrary to expectations, GE was slower with UHT-M, yet, as anticipated, aminoacidemia was greater. The larger GCV following UHT-M suggests that gastric volume may poorly predict circulating nutrient appearance from complex food matrices. Dairy heat treatment may be an effective tool to modify nutrient release by impacting digestion kinetics. CLINICAL TRIAL REGISTRY: www.anzctr.org.au (ACTRN12620000172909).

Size at birth predicts later brain volumes.

We aimed to investigate whether gestation at birth, birth weight, and head circumference at birth are still associated with brain volume and white matter microstructure at 9-10 years in children born late-preterm and at term. One hundred and eleven children born at ≥ 36 weeks gestation from the CHYLD Study cohort underwent brain magnetic resonance imaging at 9 to 10 years. Images were analysed using FreeSurfer for volumetric data and tract-based spatial statistics for diffusion data. Of the cohort, 101 children were included for volumetric analysis [boys, 49(49%); median age, 9.5 (range: 8.9-12.4) years]. Shorter gestation at birth, lower birthweight, and smaller birth head circumference were associated with smaller brain volumes at 9 to 10 years, both globally and regionally. Amongst the perinatal factors studied, head circumference at birth was the strongest predictor of later brain volumes. Gestation at birth and absolute birthweight were not associated with diffusion metrics of white matter skeleton. However, lower birthweight z-score was associated with higher fractional anisotropy and lower radial diffusivity. Our findings suggest that even in children born late preterm and at term, growth before birth and timing of birth are still associated with brain development in mid-childhood.

Associations Between Autism Spectrum Quotient and Integration of Visual Stimuli in 9-year-old Children: Preliminary Evidence of Sex Differences.

PURPOSE: The dorsal stream vulnerability hypothesis posits that the dorsal stream, responsible for visual motion and visuo-motor processing, may be particularly vulnerable during neurodevelopment. Consistent with this, autism spectrum disorder (ASD) has been associated with deficits in global motion integration, though deficits in ventral stream tasks, such as form identification, have also been reported. In the current study, we examined whether a similar pattern of results is found in a cohort of 381 children born with neurodevelopmental risk factors and exhibiting a wide spectrum of caregiver-reported autistic traits. METHODS: We examined the associations between global motion perception, global form perception, fine motor function, visual-motor integration, and autistic traits (autism spectrum quotient, AQ) using linear regression, accounting for possible interactions with sex and other factors relevant to neurodevelopment. RESULTS: All assessments of dorsal stream function were significantly associated with AQ such that worse performance predicted higher AQ scores. We also observed a significant sex interaction, with worse global form perception associated with higher AQ in boys (n = 202) but not girls (n = 179). CONCLUSION: We found widespread associations between dorsal stream functions and autistic traits. These associations were observed in a large group of children with a range of AQ scores, demonstrating a range of visual function across the full spectrum of autistic traits. In addition, ventral function was associated with AQ in boys but not girls. Sex differences in the associations between visual processing and neurodevelopment should be considered in the designs of future studies.

Mid-Childhood Outcomes after Dextrose Gel Treatment of Neonatal Hypoglycaemia: Follow-Up of the Sugar Babies Randomized Trial.

INTRODUCTION: Dextrose gel is widely used as first-line treatment for neonatal hypoglycaemia given its cost-effectiveness and ease of use. The Sugar Babies randomized trial first showed that 40% dextrose gel was more effective in reversing hypoglycaemia than feeding alone. Follow-up of the Sugar Babies Trial cohort at 2 and 4.5 years of age reported that dextrose gel appeared safe, with similar rates of neurosensory impairment in babies randomized to dextrose or placebo gel. However, some effects of neonatal hypoglycaemia may not become apparent until school age. METHODS: Follow-up of the Sugar Babies Trial cohort at 9-10 years of age was reported. The primary outcome was low educational achievement in reading or mathematics. Secondary outcomes included other aspects of educational achievement, executive function, visual-motor function, and psychosocial adaptation. RESULTS: Of 227 eligible children, 184 (81%) were assessed at a mean (SD) age of 9.3 (0.2) years. Low educational achievement was similar in dextrose and placebo groups (36/86 [42%] vs. 42/94 [45%]; RR 1.04, 95% CI 0.76, 1.44; p = 0.79). Children allocated to dextrose gel had lower visual perception standard scores (95.2 vs. 100.6; MD -5.68, 95% CI -9.79, -1.57; p = 0.006) and a greater proportion had low (<85) visual perception scores (20/88 [23%] vs. 10/95 [11%]; RR 2.23, 95% CI 1.13, 4.37; p = 0.02). Other secondary outcomes, including other aspects of visual-motor function, were similar in both groups. CONCLUSION: Treatment dextrose gel does not appear to result in any clinically significant differences in educational achievement or other neurodevelopmental outcomes at mid-childhood.

Stability of executive function in children born at risk of neonatal hypoglycemia.

Executive function plays an important role in promoting learning and social-emotional development in children. Neonatal hypoglycemia associates with executive function difficulties at 4.5 years, but little is known about the development of executive function over time in children born at risk of neonatal hypoglycemia. We aimed to describe the stability of executive function from early to mid-childhood in children born at risk of neonatal hypoglycemia and its association with neonatal hypoglycemia. Participants in a prospective cohort study of infants born at risk for neonatal hypoglycemia were assessed at ages 2, 4.5, and 9-10 years. We assessed executive function with batteries of performance-based and questionnaire-based measures, and classified children into one of four stability groups (persistent typical, intermittent typical, intermittent difficulty, and persistent difficulty) based on dichotomized scores (typical versus low at each age). Multinomial logistic regression was used to determine the associations between neonatal hypoglycemia and executive function stability groups. Three hundred and nine children, of whom 197 (64%) experienced neonatal hypoglycemia were assessed. The majority of children had stable and typical performance-based (63%) and questionnaire-based (68%) executive function across all three ages. Around one-third (30-36%) of children had transient difficulties, and only a few (0.3-1.9%) showed persistent difficulties in executive function at all ages. There was no consistent evidence of an association between neonatal hypoglycemia and the stability of executive function. Neonatal hypoglycemia does not appear to predict a specific pattern of development of executive function in children born at risk.

Associations between neonatal hypoglycaemia and brain volumes, cortical thickness and white matter microstructure in mid-childhood: An MRI study.

Neonatal hypoglycaemia is a common metabolic disorder that may cause brain damage, most visible in parieto-occipital regions on MRI in the acute phase. However, the long term effects of neonatal hypoglycaemia on the brain are not well understood. We investigated the association between neonatal hypoglycaemia and brain volumes, cortical thickness and white matter microstructure at 9-10 years. Children born at risk of neonatal hypoglycaemia at ≥ 36 weeks' gestation who took part in a prospective cohort study underwent brain MRI at 9-10 years. Neonatal hypoglycaemia was defined as at least one hypoglycaemic episode (at least one consecutive blood glucose concentration < 2.6 mmol/L) or interstitial episode (at least 10 min of interstitial glucose concentrations < 2.6 mmol/L). Brain volumes and cortical thickness were computed using Freesurfer. White matter microstructure was assessed using tract-based spatial statistics. Children who had (n = 75) and had not (n = 26) experienced neonatal hypoglycaemia had similar combined parietal and occipital lobe volumes and no differences in white matter microstructure at nine years of age. However, those who had experienced neonatal hypoglycaemia had smaller caudate volumes (mean difference: -557 mm3, 95% confidence interval (CI), -933 to -182, p = 0.004) and smaller thalamus (-0.03%, 95%CI, -0.06 to 0.00; p = 0.05) and subcortical grey matter (-0.10%, 95%CI -0.20 to 0.00, p = 0.05) volumes as percentage of total brain volume, and thinner occipital lobe cortex (-0.05 mm, 95%CI -0.10 to 0.00, p = 0.05) than those who had not. The finding of smaller caudate volumes after neonatal hypoglycaemia was consistent across analyses of pre-specified severity groups, clinically detected hypoglycaemic episodes, and severity and frequency of hypoglycaemic events. Neonatal hypoglycaemia is associated with smaller deep grey matter brain regions and thinner occipital lobe cortex but not altered white matter microstructure in mid-childhood.

The Baseline Pattern and Age-related Developmental Metabolic Changes in the Brain of Children with Autism as Measured on Positron Emission Tomography/Computed Tomography Scan.

[18F] 2-fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography scan was performed on 45 children with autism to study the baseline pattern and age-related developmental changes in the brain metabolism. Median standardized uptake values (SUVs) were compared with published healthy control data. Results showed that, in contrary to control data, the median SUVs in children with autism decrease linearly with increase in age. As compared to controls, autism children below 5 years showed greater metabolism and older children showed lower metabolism. In autism group, comparison of absolute SUVs within different regions of the brain revealed relatively lower metabolism in amygdala, hippocampus, parahippocampal gyrus, caudate nucleus, cerebellum, mesial temporal lobe, thalamus, superior and middle temporal pole, and higher metabolic uptake in calcarine fissure and Heschl's gyrus. These results help in understanding the baseline metabolism and developmental changes of brain among different age groups in autism.

An open-label proof-of-concept study of intrathecal autologous bone marrow mononuclear cell transplantation in intellectual disability.

BACKGROUND: The underlying pathophysiology in intellectual disability (ID) involves abnormalities in dendritic branching and connectivity of the neuronal network. This limits the ability of the brain to process information. Conceptually, cellular therapy through its neurorestorative and neuroregenerative properties can counteract these pathogenetic mechanisms and improve neuronal connectivity. This improved networking should exhibit as clinical efficacy in patients with ID. METHODS: To assess the safety and efficacy of cellular therapy in patients with ID, we conducted an open-label proof-of-concept study from October 2011 to December 2015. Patients were divided into two groups: intervention group (n = 29) and rehabilitation group (n = 29). The intervention group underwent cellular transplantation consisting of intrathecal administration of autologous bone marrow mononuclear cells and standard neurorehabilitation. The rehabilitation group underwent only standard neurorehabilitation. The results of the symptomatic outcomes were compared between the two groups. In the intervention group analysis, the outcome measures used were the intelligence quotient (IQ) and the Wee Functional Independence Measure (Wee-FIM). To compare the pre-intervention and post-intervention results, statistical analysis was done using Wilcoxon's matched-pairs test for Wee-FIM scores and McNemar's test for symptomatic improvements and IQ. The effect of age and severity of the disorder were assessed for their impact on the outcome of intervention. Positron emission tomography-computed tomography (PET-CT) brain scan was used as a monitoring tool to study effects of the intervention. Adverse events were monitored for the safety of cellular therapy. RESULTS: On symptomatic analysis, greater improvements were seen in the intervention group as compared to the rehabilitation group. In the intervention group, the symptomatic improvements, IQ and Wee-FIM were statistically significant. A significantly better outcome of the intervention was found in the paediatric age group (<18 years) and patients with milder severity of ID. Repeat PET-CT scan in three patients of the intervention group showed improved metabolism in the frontal, parietal cortex, thalamus, mesial temporal structures and cerebellum. No major adverse events were witnessed. CONCLUSIONS: Cellular transplantation with neurorehabilitation is safe and effective for the treatment of underlying brain deficits in ID. TRIAL REGISTRATION: ClinicalTrials.gov NCT02245724. Registered 12 September 2014.