Changes in the brain microstructure of children with primary monosymptomatic nocturnal enuresis: a diffusion tensor imaging study

Superagers Resist Typical Age-Related White Matter Structural Changes

Superagers are elderly individuals with the memory ability of people 30 years younger and provide evidence that age-related cognitive decline is not inevitable. In a sample of 64 superagers (mean age, 81.9; 59% women) and 55 typical older adults (mean age, 82.4; 64% women) from the Vallecas Project, we studied, cross-sectionally and longitudinally over 5 years with yearly follow-ups, the global cerebral white matter status as well as region-specific white matter microstructure assessment derived from diffusivity measures. Superagers and typical older adults showed no difference in global white matter health (total white matter volume, Fazekas score, and lesions volume) cross-sectionally or longitudinally. However, analyses of diffusion parameters revealed the better white matter microstructure in superagers than in typical older adults. Cross-sectional differences showed higher fractional anisotropy (FA) in superagers mostly in frontal fibers and lower mean diffusivity (MD) in most white matter tracts, expressed as an anteroposterior gradient with greater group differences in anterior tracts. FA decrease over time is slower in superagers than in typical older adults in all white matter tracts assessed, which is mirrored by MD increases over time being slower in superagers than in typical older adults in all white matter tracts except for the corticospinal tract, the uncinate fasciculus, and the forceps minor. The better preservation of white matter microstructure in superagers relative to typical older adults supports resistance to age-related brain structural changes as a mechanism underpinning the remarkable memory capacity of superagers, while their regional aging pattern is in line with the last-in-first-out hypothesis.

Abnormal microstructure of corpus callosum in children with primary nocturnal enuresis: a DTI study

Primary nocturnal enuresis (PNE) is a common childhood disorder with abnormal sleep or arousal. The corpus callosum (CC) continues to develop into adulthood and plays an important role in sleep arousal. This study aimed to evaluate the microstructure of the CC in children with PNE. Diffusion tensor imaging (DTI) indices were extracted throughout the CC and its seven subregions were compared between the children with PNE and healthy children (HC). The correlation between abnormal DTI indices of the CC and cognitive condition was also tested. Compared to HC, decreased fiber number (NF) (F = 8.492, PFDR = 0.032) and fractional anisotropy (FA) value (F = 8.442, PFDR = 0.040) were found in the posterior midbody of the CC, increased RD was found in the posterior midbody (F = 6.888, PFDR = 0.040) and isthmus (F = 7.967, PFDR = 0.040) in children with PNE. The reduction of FA value was more obvious in boys than girls with PNE. In children with PNE, there was a significant positive correlation between the NF of the posterior midbody and full IQ (r = 0.322, P = 0.025) and between the FA value and the general knowledge memory (r = 0.293, P = 0.043). This study provides imaging evidence for abnormalities in the microstructure of the CC in children with PNE, especially in male PNE, which might affect the children's cognitive performance.

Sleep-Disordered Breathing and Its Association with Nocturnal Enuresis at the Primary Schools in Saudi Arabia: A Cross-Sectional Study

The correlation between nocturnal enuresis (NE) and sleep-disordered breathing (SDB) was reported. We aim to determine whether there is an association between NE and SDB in children and to assess the prevalence of SDB and NE in primary school children aged 6-12 years in Saudi Arabia. A cross-sectional observational study was conducted among the caregivers of children aged 6-12 years in all Saudi Arabia regions. The data were gathered through a self-administered online questionnaire. It included demographic information, weight and height, and associated comorbidities, in addition to the weekly frequencies of snoring symptoms and of enuresis, as well as of unrefreshing sleep using Likert-type response scales. Counts and percentages, the mean ± standard deviation, chi-square test, independent samples t-test, and regression analysis were used in the statistical analysis using R v 3.6.3. The questionnaire was completed by 686 respondents. Most respondents did not report any comorbidities in their children (77.1%). Asthma and adenotonsillar hypertrophy were reported in 16.2% and 15.6% of children, respectively. Unrefreshing sleep, mouth breathing at night, snoring, chronic nasal obstruction, and difficulty breathing while asleep were reported once or twice per week in 38%, 34%, 28%, 18%, and 18% of children, respectively. The prevalence of NE was 22.3%, with about 36.6% of children having NE two or more times per week. Significantly, NE was reported in 26.6% of children who slept before 10 PM compared to 19% of children who slept after 10 PM; in 28.6% of children who snored or loudly snored (57.1%) three times or more per week; and in 51.2% and 27.5% of children with difficulty breathing while asleep and who breathed through their mouth at night for one or two nights per week, respectively. A multivariable regression analysis showed that male gender (OR = 1.52, p = 0.010), obesity (OR = 1.24, p = 0.028), early sleeping time (OR = 1.40, p = 0.048), loud snoring for three or more nights per week (OR = 1.54, p = 0.001), difficulty breathing for one or two nights per week (OR = 1.85, p = 0.010), and mouth breathing at night for one or two nights per week (OR = 1.55, p = 0.049) were associated with higher odds of NE. Our study revealed that 22.3% of primary school children reported suffering from NE. SDB is a common problem among children with NE. The exact mechanism that links SDB to the increase in the risk of NE is unknown. Male gender, obesity, early sleeping time, loud snoring, difficulty breathing, and mouth breathing at night are potential independent risk factors of NE in school-age children.

Anxiety disorders, depression and incontinence in preschool children-A population-based study

OBJECTIVE

The aim was to examine associations of specific anxiety disorders, depressive symptoms, and incontinence in a representative, population-based sample of preschool children.

METHODS

All preschool children of a defined geographical area examined before school-entry were included. Parents completed a questionnaire including the Preschool Feelings Checklist (PFC), eight questions referring to nocturnal enuresis (NE), daytime urinary incontinence (DUI), fecal incontinence (FI) and constipation, and 30 items regarding Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-5) diagnostic criteria of separation anxiety disorder (SAD), social phobia (SOC), specific phobia (PHOB), and generalized anxiety disorder (GAD). Data of 1206 children (mean age = 5.7 years; 53.5% boys) are presented.

RESULTS

34.6% of incontinent children had an anxiety disorder based on DSM-5 criteria and 13.3% had clinically relevant depressive symptoms (measured by the PFC). Rates of incontinence overall were 14.1% (11.9% NE, 3.1% DUI, and 1.8% FI) and 6.3% for constipation. Rates of SOC and PHOB were increased in NE (20.8% and 25.4%), DUI (39.3% and 34.5%) and FI (35.3% and 50.0%) compared to continent children (13.5% and 17.2%). Children with constipation had higher rates of SOC, PHOB, and GAD than those without. Compared to continent children (9.7%), depressive symptoms were more frequent in children with NE (26.8%), DUI (50.0%), and FI (61.9%).

CONCLUSION

Anxiety disorders and depressive symptoms are common in children with incontinence. The most specific DSM-5 disorders associated with incontinence are SOC and PHOB, which can be incapacitating and may require treatment. Due to the high rates of anxiety disorders, it is important to screen all children with incontinence, for example, with specific questionnaires.

Altered resting-state functional connectivity of insula in children with primary nocturnal enuresis

Objective

Primary nocturnal enuresis (PNE) is a common developmental condition in school-aged children. The objective is to better understand the pathophysiology of PNE by using insula-centered resting-state functional connectivity (rsFC).

Methods

We recruited 66 right-handed participants in our analysis, 33 with PNE and 33 healthy control (HC) children without enuresis matched for gender and age. Functional and structural MRI data were obtained from all the children. Seed-based rsFC was used to examine differences in insular functional connectivity between the PNE and HC groups. Correlation analyses were carried out to explore the relationship between abnormal insula-centered functional connectivity and clinical characteristics in the PNE group.

Results

Compared with HC children, the children with PNE demonstrated decreased left and right insular rsFC with the right medial superior frontal gyrus (SFG). In addition, the bilateral dorsal anterior insula (dAI) seeds also indicated the reduced rsFC with right medial SFG. Furthermore, the right posterior insula (PI) seed showed the weaker rsFC with the right medial SFG, while the left PI seed displayed the weaker rsFC with the right SFG. No statistically significant correlations were detected between aberrant insular rsFC and clinical variables (e.g., micturition desire awakening, bed-wetting frequency, and bladder volume) in results without global signal regression (GSR) in the PNE group. However, before and after setting age as a covariate, significant and positive correlations between bladder volume and the rsFC of the left dAI with right medial SFG and the rsFC of the right PI with right medial SFG were found in results with GSR in the PNE group.

Conclusion

To the best of our knowledge, this study explored the rsFC patterns of the insula in children with PNE for the first time. These results uncovered the abnormal rsFC of the insula with the medial prefrontal cortex without and with GSR in the PNE group, suggesting that dysconnectivity of the salience network (SN)-default mode network (DMN) may involve in the underlying pathophysiology of children with PNE. However, the inconsistent associations between bladder volume and dysconnectivity of the SN-DMN in results without and with GSR need further studies.

Effect of DRD4 Receptor -616 C/G Polymorphism on Thalamic GABA Levels in Pediatric Patients With Primary Nocturnal Enuresis

BACKGROUND

The single nucleotide polymorphism (SNP) of dopamine D4 receptor (DRD4) promoter (-616; rs747302) is associated with abnormalities of the thalamus in children suffering from primary nocturnal enuresis (PNE).

PURPOSE

To investigate the effect of DRD4 -616 C/G SNP on thalamic gamma-aminobutyric acid (GABA) levels in PNE children.

STUDY TYPE

Prospective, observational.

SUBJECTS

One hundred and seventy-six children with PNE and 161 healthy control children.

FIELD STRENGTH/SEQUENCE

3 T, three-dimensional T1-weighted turbo field echo sequence and MEscher-Garwood Point RESolved Spectroscopy (MEGA-PRESS) MRS sequence.

ASSESSMENT

The MEGA-PRESS MRS sequence was used to measure thalamic GABA spectra. The thalamic GABA+ level was calculated using the Gannet 3.0 software package for each participant. A questionnaire was used to determine arousal from sleep (AS) scores.

STATISTICAL TESTS

Comparisons of the AS scores and thalamic GABA+ levels were performed using the Mann-Whitney U test between C-allele carriers and GG homozygotes in the PNE and control groups. Spearman correlation analysis was performed to determine the association between AS scores and thalamic GABA levels in PNE children.

RESULTS

Thalamic GABA levels in the PNE group were significantly higher than those in the healthy control group (0.178 (0.169-0.186) vs. 0.154 (0.146-0.164), Z = 8.526, P_corrected  < 0.001). The GABA levels in C-allele carriers were significantly higher than those in GG homozygotes in both the PNE and control groups (0.184 (0.181-0.193) vs. 0.170 (0.165-0.177), Z = 8.683, P_corrected  < 0.001; 0.166 (0.156-0.170) vs. 0.147 (0.141-0.152), Z = 9.445, P_corrected  < 0.001). GABA levels in the thalamus were also significantly and positively correlated with AS scores in C-allele carriers in the PNE group (r = 0.747, P < 0.05).

DATA CONCLUSION

DRD4 -616 C allele may be associated with increased thalamic GABA+ levels, especially in C-allele carrying PNE children.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 3.

Frequency-specific alterations of the resting-state BOLD signals in nocturnal enuresis: an fMRI Study

Resting state functional magnetic resonance imaging studies of nocturnal enuresis have focused primarily on regional metrics in the blood oxygen level dependent (BOLD) signal ranging from 0.01 to 0.08 Hz. However, it remains unclear how local metrics show in sub-frequency band. 129 children with nocturnal enuresis (NE) and 37 healthy controls were included in this study. The patients were diagnosed by the pediatricians in Shanghai Children's Medical Center affiliated to Shanghai Jiao Tong University School of Medicine, according to the criteria from International Children's Continence Society (ICCS). Questionnaires were used to evaluate the symptoms of enuresis and completed by the participants. In this study, fALFF, ReHo and PerAF were calculated within five different frequency bands: typical band (0.01-0.08 Hz), slow-5 (0.01-0.027 Hz), slow-4 (0.027-0.073 Hz), slow-3 (0.073-0.198 Hz), and slow-2 (0.198-0.25 Hz). In the typical band, ReHo increased in the left insula and the right thalamus, while fALFF decreased in the right insula in children with NE. Besides, PerAF was increased in the right middle temporal gyrus in these children. The results regarding ReHo, fALFF and PerAF in the typical band was similar to those in slow-5 band, respectively. A correlation was found between the PerAF value of the right middle temporal gyrus and scores of the urinary intention-related wakefulness. Results in other bands were either negative or in white matter. NE children might have abnormal intrinsic neural oscillations mainly on slow-5 bands.

Functional connectivity of thalamus in children with primary nocturnal enuresis: results from a resting-state fMRI study

Primary nocturnal enuresis (PNE) is characterized by a low cure rate and a high reoccurrence rate, since its underlying mechanism remains unclear. Based on the recent studies that thalamus plays an important role in waking up a sleeping person, here we further investigate the functional connectivity (FC) information between thalamus and other brain regions, in order to make better understanding of the PNE's pathogenesis. In this study, we enrolled 30 children diagnosed with PNE and 30 typically developing children that are age and sex matched, the thalamus-based FC estimates were extracted at the resting-state. Experiments showed that for children with PNE, there were four brain regions found with a reduced connection efficiency with thalamus, that were cerebellum posterior lobe, frontal lobe, parietal lobe and precentral gyrus. It can be concluded that these relevant regions might induce an arousal disorder, and therefore further lead to PNE. This finding also provides a new insight in the pathophysiology of PNE.

Pathogenesis and brain functional imaging in nocturnal enuresis: A review

Nocturnal enuresis is a common and distressing developmental disease, which may cause various degrees of psychosocial stress and impairment to self-esteem in affected children as well as agitation to their parents or caregivers. Nevertheless, the etiology and pathogenesis of nocturnal enuresis are not understood. Currently, nocturnal enuresis is generally considered a multifactorial disease associated with a complex interaction of somatic, psychosocial, and environmental factors. A variety of postulations have been proposed to explain the occurrence and progression of nocturnal enuresis, including hereditary aberration, abnormal circadian rhythm of antidiuretic hormone secretion during sleep, bladder dysfunction, abnormal sleep, difficulties in arousal, neuropsychological disorders, and maturational delays of the brain. In recent decades, the introduction of functional neuroimaging technologies has provided new approaches for uncovering the mechanisms underlying nocturnal enuresis. The main neuroimaging modalities have included brain morphometry based on structural magnetic resonance imaging (MRI), task-based and event-related functional MRI (fMRI), and resting-state fMRI. The relevant studies have indicated that nocturnal enuresis is associated with functional and structural alterations of the brain. In this review, we briefly summarized the popular hypotheses regarding the pathogenesis of nocturnal enuresis and the current progress of functional neuroimaging studies in examining the underlying mechanisms thereof.

Abnormal neurite orientation dispersion and density imaging of white matter in children with primary nocturnal enuresis

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NODDI probes white matter (WM) microstructure in PNE children.

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Different patterns of WM microstructural abnormalities were found in PNE children.

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NDI of anterior thalamic radiation was correlated with abnormal arousal in PNE children.

Several lines of evidence indicate that multiple abnormalities of gray matter are related to the pathogenesis of primary nocturnal enuresis (PNE); however, few studies have been conducted with respect to abnormalities in white matter (WM) of children with PNE. The present work investigated the microstructure of WM in children with PNE using a neurite orientation dispersion and density imaging (NODDI) method. NODDI data were obtained from 29 children with PNE (age = 9.8 ± 1.2 years, 59% males) and 34 healthy controls (age = 10.3 ± 1.6 years, 56% males) in this study. Multi-b-value diffusion-weighted imaging data were acquired with a 3 T MR system, and the orientation dispersion index (ODI) and neurite density index (NDI) maps were calculated. Tract-Based Spatial Statistics analyses of WM tracts were performed with ODI and NDI maps in children with PNE and controls. Children with PNE had lower ODIs in WM fiber tracts of the bilateral superior longitudinal fasciculus (SLF) and higher ODIs in the bilateral internal capsule (IC) and right anterior thalamic radiation (ATR) than controls. PNE children also had lower NDIs in the bilateral IC and the cingulum and higher NDIs in the bilateral SLF. These changes in NODDI indices, which indicated abnormal neural maturation of the WM microstructures, may be related to abnormal sleep and enuresis in children with PNE.

Abnormal Thalamic Functional Connectivity During Light Non-Rapid Eye Movement Sleep in Children With Primary Nocturnal Enuresis

OBJECTIVE

To investigate abnormalities of thalamocortical and intrathalamic functional connectivity (FC) in children with primary nocturnal enuresis (PNE) during light non-rapid eye movement (NREM) sleep using a simultaneous electroencephalography (EEG)-functional magnetic resonance imaging (fMRI) method.

METHOD

Polysomnographic and EEG-fMRI data were obtained during sleep from 61 children with PNE (age 10.2 ± 1.7 years, 59% boys) and 61 age-matched controls (age 10.1 ± 1.4 years, 54% boys). All subjects first participated in one overnight video-polysomnographic study. Total sleep time, percentage of total sleep time in each sleep stage, arousal index, and awakening index were calculated. Simultaneous EEG-fMRI studies were then performed using a 3T MRI system with a 32-channel MRI-compatible EEG system. Visual scoring of EEG data permitted sleep staging. Thalamocortical and intrathalamic FCs in the waking state and at different stages of light sleep were calculated and compared.

RESULTS

Children with PNE had a higher percentage of total sleep time in light sleep and a higher arousal index compared with controls. Abnormal thalamocortical FCs were detected in the lateral prefrontal cortex, medial prefrontal cortex, and inferior parietal lobule during light NREM sleep. Abnormal intrathalamic FCs were also detected during light NREM sleep among the motor, occipital, prefrontal, and temporal subdivisions of the thalamus.

CONCLUSION

Abnormal prefrontal and parietal thalamocortical FCs, accompanied by abnormal intrathalamic FCs among the motor, occipital, prefrontal, and temporal subdivision of thalamus during light NREM sleep, may be related to abnormal sleep and enuresis in children with PNE.

Evaluation of neuropsychological development of children diagnosed with primary monosymptomatic nocturnal enuresis: A pilot study

OBJECTIVE

Studies on primary monosymptomatic nocturnal enuresis have supported neuromotor development delay. This study aims to examine the neuropsychological development of children with primary monosymptomatic nocturnal enuresis.

MATERIAL AND METHODS

This study included 30 children diagnosed with primary monosymptomatic nocturnal enuresis and 30 healthy children. Both groups were analyzed by pediatric psychologists using the Wechsler Intelligence Scale for Children-Revised (WISC-R) and the Bender Gestalt Visual Motor Detection test. The WISC-R test is an intelligence test that includes six verbal subscales (information, similarities, arithmetic, vocabulary, judgment, and digit span) and six performance subscales (picture completion, picture arrangement, block design, object assembly, coding, and labyrinths). The Bender Gestalt test is a psychological assessment instrument used to evaluate visuomotor functioning, visuospatial functions, spatial memory, visuomotor integration skills, and visual perception skills.

RESULTS

There were no differences in age (7.66±0.9 versus 8±1.07 years, p>0.05) or sex (20 females versus 20 males, p>0.05) between the groups. Picture completion (p=0.024), picture arrangement (p=0.001), and object assembly test (p=0.000) performance was found to be worse in subjects with primary monosymptomatic nocturnal enuresis. Similarity (p=0.021) and judgment tests (p=0.048) of the verbal subtests were also found to be delayed in the nocturnal enuresis cases.

CONCLUSION

Our results suggest that children with nocturnal enuresis have lower performance compared with the control group in terms of abstract thinking, correct expression of thought, cause-result relation, short-term memory, and problem-solving ability. These children should be routinely tested by neurodevelopment tests and receive support in areas in which they are delayed.

Associations Between Psychiatric Disorders and Enuresis in Taiwanese Children: A National Population-Based Study

BACKGROUND

Psychiatric disorders such as attention-deficit/hyperactivity disorder may negatively impact drug compliance and the prognosis of enuresis. However, existing studies regarding associations between lifetime psychiatric disorders and childhood enuresis are primarily from Western countries, and studies from Taiwan are lacking.

METHODS

We conducted a population-based retrospective cohort analysis using the Taiwan Longitudinal Health Insurance Database 2010. A total of 1,146 children with enuresis (ICD-9-CM code: 307.6) and 4,584 randomly selected sex- and age-matched controls were identified between January 1, 1997 and December 31, 2011. Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for the development of psychiatric disorders in the children with enuresis.

RESULTS

Enuresis was more common in the younger children, and the rate was significantly higher in boys (58.7%) than in girls (41.3%). A total of 171 patients (14.9%) in the enuresis group had at least one psychiatric diagnosis vs 259 (5.7%) in the control group (p<0.001). Multivariate analysis showed that the presence of enuresis increased the odds of developing major depressive/dysthymic disorder (OR=2.841, 95% CI: 1.619, 4.987), attention-deficit/hyperactivity disorder (OR=3.156, 95% CI: 2.446, 4.073), autism spectrum disorder (OR=2.468, 95% CI: 1.264, 4.822), anxiety disorders (OR=3.113, 95% CI: 2.063, 4.699), intelligence disability (OR=3.989, 95% CI: 2.476, 6.426), disruptive behavior disorders (OR=3.749, 95% CI: 1.756, 8.004), and tic disorder (OR=2.660, 95% CI: 1.642, 4.308).

CONCLUSION

Children with enuresis are likely to have psychiatric disorders, and physicians should consider this during their evaluation.

Abnormal neural responses to emotional stimuli in children with primary monosymptomatic nocturnal enuresis

Nocturnal enuresis (NE) is a common disorder in school-aged children that has been reported to affect nearly 10% of 7-year-old children and affects both the children and their families. Previous studies have shown that the risk of psychosocial difficulties in children with enuresis is elevated. Thus, children with NE may experience negative effects on psychosocial health or emotion processing. Therefore, the aim of this study was to investigate the potential disturbance in emotional processing in children with NE using functional magnetic resonance imaging (fMRI). In this work, we used fMRI and an affective picture task to evaluate brain response changes in children with NE. Two groups, one consisting of 22 children with primary monosymptomatic NE and one with 23 healthy controls, were scanned using fMRI. Compared to the healthy subjects, children with NE mainly showed increased activation when viewing negative vs. neutral pictures in the bilateral medial superior frontal gyrus that extended to the anterior cingulate cortex. Our results demonstrated that children with primary monosymptomatic NE showed abnormal neural responses to emotional stimuli and overactivation in the medial prefrontal and anterior cingulate cortices suggested that children with primary monosymptomatic NE may be hypersensitive in their sensory perception of negative pictures.

Nocturnal enuresis in obese children: a nation-wide epidemiological study from China

Childhood obesity increases the risk of obstructive sleep apnea syndrome, type 2 diabetes mellitus, cardiovascular abnormalities, and psychological and behavioral disorders. But it is unclear whether obesity is associated with childhood nocturnal enuresis (NE). This study aimed to assess the relationship between childhood obesity and NE in a nationally representative large sample in China. Subjects were enrolled from Urumqi, Chengdu, Xi'an, Hohhot, Wuhan, Canton, Shanghai, and Harbin cities in China in November and December 2005. The survey included 20,987 children aged 5-12 years and they and their caregivers completed questionnaires. Height and weight were measured by school teachers trained in healthcare. According to the WHO child growth standards, obesity was defined as a body mass index >95th percentile of peers with the same age and gender. NE was defined as bed wetting for more than twice a week for 3 consecutive months. Demographic variables were compared among different groups. The prevalence of obesity, asthma, attention-deficit/hyperactivity disorder (ADHD), depressive moods, and snoring were different between the NE and without-NE groups (P < 0.05). The raw odds ratio (OR) for NE and obesity was 1.36 (95%CI = 1.07-1.74; P = 0.013) and the adjusted OR was 1.42 (95%CI = 1.11-1.82; P = 0.005) in the multivariable analysis. When adjusting for co-occurring conditions, the results showed that asthma did not affect the risk of NE (OR = 1.42, 95%CI = 1.11-1.82; P = 0.005), but ADHD (OR = 1.41; 95%CI = 1.10-1.81; P = 0.006) and depressive moods (OR = 1.34; 95%CI = 1.07-1.76; P = 0.012) slightly weakens the association between NE in children and obesity, while snoring weakens the association between obesity and NE and the risk became non-significant (OR = 1.21; 95%CI = 0.94-1.56; P = 0.138). In conclusion, obese children were at a higher risk of incurring NE compared to non-obese children. This association was weaker in children who either snored, had ADHD, or had depressive mood.

Morphometric Magnetic Resonance Imaging Study in Children With Primary Monosymptomatic Nocturnal Enuresis

OBJECTIVE

Primary monosymptomatic nocturnal enuresis (PMNE) refers to bed-wetting in children who have no other lower urinary tract symptoms and are never dry for more than 6 months. Our previous studies demonstrated that children with PMNE exhibited brain functional abnormalities compared with healthy controls; however, researches on the abnormalities in gray matter were limited. This study aimed to investigate brain structural changes in gray matter of children with PMNE using magnetic resonance imaging (MRI).

METHODS

Gray matter volumes (GMVs) and gyrification indices (GIs) were calculated using voxel-based and surface-based morphometry analyses of structural MRI data acquired from 26 children with PMNE and 28 healthy children. To identify between-group differences in gray matter, two-sample t-tests were conducted on GMV and GI images separately.

RESULTS

Compared with the controls, children with PMNE showed significantly increased GMVs in the supplementary motor area and medial prefrontal cortex regions (mean GMV in PMNE: 0.54 ± 0.07 l; mean GMV in controls: 0.50 ± 0.06 l) and reduced GIs in the right precuneus (mean GI in PMNE: 25.74° ± 2.34°; mean GI in controls: 27.97° ± 1.79°).

CONCLUSION

Children with PMNE showed abnormal GMVs in frontal lobe and GIs in precuneus, and these changes might be involved in the pathological mechanism of PMNE.

Effect of DRD4 receptor -616 C/G polymorphism on brain structure and functional connectivity density in pediatric primary nocturnal enuresis patients

The dopamine D4 receptor (DRD4) promoter (-616; rs747302) has been associated with primary nocturnal enuresis (PNE); however, its relationship with neuroimaging has not been investigated. Therefore, we assessed the effects of the DRD4 -616 C/G single nucleotide polymorphism on the gray matter volume (GMV) and functional connectivity density (FCD) during resting-state functional magnetic resonance imaging in children with PNE using voxel-based morphometry and FCD methods. Genomic and imaging data were obtained from 97 children with PNE and 105 healthy controls. DRD4 -616 C/G was genotyped. Arousal from sleep (AS) was assessed on a scale of 1-8. Both the main effect of genotype and the group (PNE/control)-by-genotype interaction on GMV and FCD were calculated. Our results showed that C-allele carriers were associated with a higher AS, decreased GMV and FCD in the pregenual anterior cingulate cortex; children with PNE carrying the C allele exhibit decreased GMV and FCD in the thalamus; however, controls carrying the C allele exhibit increased FCD in the posterior cingulate cortex. These effects of genetic variation of the DRD4 locus may help us understand the genetic susceptibility of the DRD4 -616 C allele to PNE.

Noninvasive imaging of brain oxygen metabolism in children with primary nocturnal enuresis during natural sleep

A series of studies have revealed that nocturnal enuresis is closely related to hypoxia in children with primary nocturnal enuresis (PNE). However, brain oxygen metabolism of PNE children has not been investigated before. The purpose of this study was to investigate changes in whole-brain cerebral metabolic rate of oxygen (CMRO₂ ), cerebral blood flow (CBF), and oxygen extraction fraction (OEF) in children suffering from PNE. We used the newly developed T2-relaxation-under-spin-tagging (TRUST) magnetic resonance imaging technique. Neurological evaluation, structural imaging, phase-contrast, and the TRUST imaging method were applied in children with PNE (n = 37) and healthy age- and sex-matched control volunteers (n = 39) during natural sleep to assess whole-brain CMRO₂ , CBF, OEF, and arousal from sleep scores. Results showed that whole-brain CMRO₂ and OEF values of PNE children were higher in controls, while there was no significant difference in CBF. Consequently, OEF levels of PNE children were increased to maintain oxygen supply. The elevation of OEF was positively correlated with the difficulty of arousal. Our results provide the first evidence that high oxygen consumption and high OEF values could make PNE children more susceptible to hypoxia, which may induce cumulative arousal deficits and make them more prone to nocturnal enuresis. Hum Brain Mapp 38:2532-2539, 2017. © 2017 Wiley Periodicals, Inc.

Pathophysiological and Therapeutic Considerations for Non-Neurogenic Lower Urinary Tract Dysfunction in Children

Non-neurogenic lower urinary tract dysfunction (LUTD) in children is very common in clinical practice and is important as an underlying cause of lower urinary tract symptoms, urinary tract infection and vesicoureteral reflux in affected children. LUTD in children is caused by multiple factors and might be related with a delay in functional maturation of the lower urinary tract. Behavioral and psychological problems often co-exist in children with LUTD and bowel dysfunction. Recent findings in functional brain imaging suggest that bladder bowel dysfunction and behavioral and psychiatric disorders in children might share common pathophysiological factors in the brain. Children with suspected LUTD should be evaluated properly by detailed history taking, validated questionnaire on voiding and defecation, voiding and bowel diary, urinalysis, screening ultrasound, uroflowmetry and post-void residual measurement. Invasive urodynamic study such as videourodynamics should be reserved for children in whom standard treatment fails. Initial treatment of non-neurogenic LUTD is standard urotherapy comprising education of the child and family, regular optimal voiding regimens and bowel programs. Pelvic floor muscle awareness, biofeedback and neuromodulation can be used as a supplementary purpose. Antimuscarinics and α-blockers are safely used for overactive bladder and dysfunctional voiding, respectively. For refractory cases, botulinum toxin A injection is a viable treatment option. Prudent use of urotherapy and pharmacotherapy for non-neurogenic LUTD should have a better chance to cure various problems and improve self-esteem and quality of life in affected children.

Abnormal Neural Responses to Emotional Stimuli but Not Go/NoGo and Stroop Tasks in Adults with a History of Childhood Nocturnal Enuresis

Background

Nocturnal enuresis (NE) is a common disorder in school-aged children. Previous studies have reported that children with NE exhibit structural, functional and neurochemical abnormalities in the brain, suggesting that children with NE may have cognitive problems. Additionally, children with NE have been shown to process emotions differently from control children. In fact, most cases of NE resolve with age. However, adults who had experienced NE during childhood may still have potential cognitive or emotion problems, and this possibility has not been thoroughly investigated.

Methodology/Principal Findings

In this work, we used functional magnetic resonance imaging (fMRI) to evaluate brain functional changes in adults with a history of NE. Two groups, consisting of 21 adults with NE and 21 healthy controls, were scanned using fMRI. We did not observe a significant abnormality in activation during the Go/NoGo and Stroop tasks in adults with a history of NE compared with the control group. However, compared to healthy subjects, young adults with a history of NE mainly showed increased activation in the bilateral temporoparietal junctions, bilateral dorsolateral prefrontal cortex, and bilateral anterior cingulate cortex while looking at negative vs. neutral pictures.

Conclusions/Significance

Our results demonstrate that adults with a history of childhood NE have no obvious deficit in response inhibition or cognitive control but showed abnormal neural responses to emotional stimuli.

Task positive and default mode networks during a working memory in children with primary monosymptomatic nocturnal enuresis and healthy controls

BACKGROUND

Nocturnal enuresis is a common developmental disorder in children, and primary monosymptomatic nocturnal enuresis (PMNE) is the dominant subtype.

METHODS

This study investigated brain functional abnormalities that are specifically related to working memory in children with PMNE using function magnetic resonance imaging (fMRI) in combination with an n-back task. Twenty children with PMNE and 20 healthy children, group-matched for age and sex, participated in this experiment.

RESULTS

Several brain regions exhibited reduced activation during the n-back task in children with PMNE, including the right precentral gyrus and the right inferior parietal lobule extending to the postcentral gyrus. Children with PMNE exhibited decreased cerebral activation in the task-positive network, increased task-related cerebral deactivation during a working memory task, and longer response times.

CONCLUSION

Patients exhibited different brain response patterns to different levels of working memory and tended to compensate by greater default mode network deactivation to sustain normal working memory function. Our results suggest that children with PMNE have potential working memory dysfunction.

Connectome-Scale Assessments of Functional Connectivity in Children with Primary Monosymptomatic Nocturnal Enuresis

Primary monosymptomatic nocturnal enuresis (PMNE) is a common developmental disorder in children. Previous literature has suggested that PMNE not only is a micturition disorder but also is characterized by cerebral structure abnormalities and dysfunction. However, the biological mechanisms underlying the disease are not thoroughly understood. Graph theoretical analysis has provided a unique tool to reveal the intrinsic attributes of the connectivity patterns of a complex network from a global perspective. Resting-state fMRI was performed in 20 children with PMNE and 20 healthy controls. Brain networks were constructed by computing Pearson's correlations for blood oxygenation level-dependent temporal fluctuations among the 2 groups, followed by graph-based network analyses. The functional brain networks in the PMNE patients were characterized by a significantly lower clustering coefficient, global and local efficiency, and higher characteristic path length compared with controls. PMNE patients also showed a reduced nodal efficiency in the bilateral calcarine sulcus, bilateral cuneus, bilateral lingual gyri, and right superior temporal gyrus. Our findings suggest that PMNE includes brain network alterations that may affect global communication and integration.

Microstructural abnormalities in children with post-traumatic stress disorder: a diffusion tensor imaging study at 3.0T

Posttraumatic stress disorder (PTSD) is a severe anxiety disorder characterized by re-experiencing, avoidance and hyperarousal. Brain microstructure abnormalities in PTSD, especially in children, are not yet well characterized. The aim of this study was to use MR diffusion tensor imaging (DTI) to identify brain microstructure alterations in children with PTSD compared to non-PTSD controls who experienced the same time-limited trauma. We studied 27 children with PTSD and 24 age- and gender-matched traumatized controls without PTSD, who all experienced the 2008 Sichuan major earthquake. DTI data were acquired and analyzed in terms of fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD). Children with PTSD showed an abnormal pattern, not only of FA, but also of the diffusivity measures MD, AD and RD. Most of the abnormal brain regions belonged to two important networks: the default-mode network, including precuneus and angular gyrus, and the salience network, including insula, putamen and thalamus. This DTI study identifies microstructural abnormalities of children with PTSD after a major earthquake, our results are consistent with the suggestion that pediatric PTSD is accompanied by a connectivity disequilibrium between the salience and default-mode networks, a finding of potential pathophysiological significance.

Comorbidity of ADHD and incontinence in children

ADHD and incontinence are common childhood disorders which co-occur at much higher rates than expected by chance. The aim of this review was to provide an overview both of the comorbidity of nocturnal enuresis (NE), daytime urinary incontinence (DUI) and faecal incontinence (FI) in children with ADHD; and, vice versa, of the co-occurrence of ADHD in children with NE, DUI and FI. Most clinical studies have focussed on the association of ADHD and NE. Population-based studies have shown that children with DUI have an even greater risk for ADHD than those with NE. While children with FI have the highest overall comorbidity rates of psychological disorders, these are heterogeneous with a wide range of internalising and externalising disorders--not necessarily of ADHD. Genetic studies indicate that ADHD and NE, DUI and FI do not share the same genetic basis. The comorbidity is conferred by non-genetic factors. Possible aetiological and pathogenetic links between ADHD and incontinence are provided by neurophysiological, imaging and pharmacological studies. The co-occurrence has clinical implications: children with ADHD and NE, DUI and FI are more difficult to treat, show lower compliance and have less favourable treatment outcomes for incontinence. Therefore, both groups of disorders have to be assessed and treated specifically.

Microstructural abnormalities in the combined and inattentive subtypes of attention deficit hyperactivity disorder: a diffusion tensor imaging study

Previous research has demonstrated that there are specific white matter abnormalities in patients with attention deficit/hyperactivity disorder (ADHD). However, the results of these studies are not consistent, and one of the most important factors that affects the inconsistency of previous studies maybe the ADHD subtype. Different ADHD subtypes may have some overlapping microstructural damage, but they may also have unique microstructural abnormalities. The objective of this study was to investigate the microstructural abnormalities associated with two subtypes of ADHD: combined (ADHD-C) and inattentive (ADHD-I). Twenty-eight children with ADHD-C, 28 children with ADHD-I and 28 healthy children participated in this study. Fractional anisotropy (FA), radial diffusivity (RD) and axial diffusivity (AD) were used to analyze diffusion tensor imaging (DTI) data to provide specific information regarding abnormal brain areas. Our results demonstrated that ADHD-I is related to abnormalities in the temporo-occipital areas, while the combined subtype (ADHD-C) is related to abnormalities in the frontal-subcortical circuit, the fronto-limbic pathway, and the temporo-occipital areas. Moreover, an abnormality in the motor circuit may represent the main difference between the ADHD-I and ADHD-C subtypes.

Brain metabolite alterations in children with primary nocturnal enuresis using proton magnetic resonance spectroscopy

Nocturnal enuresis is a common developmental disorder in children; primary monosymptomatic nocturnal enuresis (PMNE) is the dominant subtype. Previous literature has suggested that the prefrontal cortex and the pons are both involved in micturition control. This study aimed to investigate the metabolic levels of the left prefrontal cortex and the pons in children with PMNE by proton magnetic resonance spectroscopy (1H-MRS). Twenty-five children with PMNE and 25 healthy children took part in our experiments. Magnetic resonance examinations were performed on a Siemens 3T Trio Tim scanner. For each subject, localized 1H-MRS was acquired from the left prefrontal cortex (mainly in brodmann area 9) and the pons with a point-resolved spectroscopy sequence with repetition time 2,000 ms, echo time 30 ms and 64 averages. The LCModel software package was used to analyze the MRS raw data, and two-sample t tests were used to determine significant differences between the two groups. The results revealed a significant reduction in metabolite to total creatine ratios of N-acetylaspartate (NAA/tCr) in the left prefrontal cortex and the pons for children with PMNE compared to healthy children. Our study suggests that metabolism is disturbed in the prefrontal cortex and the pons in children with PMNE, which may be associated with the symptoms of enuresis.

Visuomotor competencies and primary monosymptomatic nocturnal enuresis in prepubertal aged children

BACKGROUND

Primary monosymptomatic nocturnal enuresis (PMNE) is a common problem in the developmental ages; it is the involuntary loss of urine during the night in children older than 5 years of age. Several clinical observations have suggested an association between bedwetting and developmental delays in motricity, language development, learning disability, physical growth, and skeletal maturation. The aim of the present study is to evaluate the prevalence of fine motor coordination and visuomotor integration abnormalities in prepubertal children with PMNE.

METHODS

The study population included 31 children (16 males, 15 females; mean age 8.14 years ± 1.36 years), and the control group comprised 61 typical developing children (32 males, 29 females; mean age 8.03 years ± 1.44 years). The whole population underwent a clinical evaluation to assess total intelligence quotient level, visuomotor integration (VMI) skills, and motor coordination performance (using the Movement Assessment Battery for Children, or M-ABC).

RESULTS

No significant differences between the two study groups were found for age (P = 0.725), gender (P = 0.886), z-body mass index (P = 0.149), or intellectual abilities (total intelligence quotient) (P = 0.163). The PMNE group showed a higher prevalence of borderline performance on M-ABC evaluation and in pathologic performance on VMI Total Task compared to controls (P < 0.001). No significant differences between the two study groups were found for pathologic performances on the M-ABC (P = 0.07), VMI Visual Task (P = 0.793), and VMI Motor Task (P = 0.213).

CONCLUSION

Our findings pinpointed that PMNE should not be considered as a voiding disorder alone and, consequently, the children affected should be referred to specific rehabilitative programs that aim to improve motor coordination and visuomotor integration.

Lower health related quality of life and psychosocial difficulties in children with monosymptomatic nocturnal enuresis--is snoring a marker of severity?

PURPOSE

Sleep disordered breathing in children is linked to numerous negative psychosocial consequences, including lower health related quality of life, increased behavioral problems and impaired neuropsychological functioning. We examined whether snoring, which is the least severe form of sleep disordered breathing, or health related quality of life could account for the increased rate of psychosocial difficulty in children with monosymptomatic nocturnal enuresis.

MATERIALS AND METHODS

Patients diagnosed with monosymptomatic nocturnal enuresis seen at an outpatient pediatric urology clinic completed measures of health related quality of life (Obstructive Sleep Apnea Syndrome-18-Item Questionnaire), sleep disordered breathing (Pediatric Sleep Questionnaire) and psychosocial difficulty (Pediatric Symptom Checklist). Patients were categorized into 2 groups (snoring vs no snoring) based on the Pediatric Symptom Checklist snoring subscale score.

RESULTS

Included in the study were 62 males and 45 females with a mean ± SD age of 9.09 ± 2.58 years and a mean body mass index of 21.00 ± 6.93 kg/m(2) (range 13 to 49). The sample was evenly split between 56 snorers (52.3%) and 51 nonsnorers (47.7%). Compared to children with monosymptomatic nocturnal enuresis who did not snore, MANCOVA results revealed that patients with monosymptomatic nocturnal enuresis who snored had significantly more externalizing problems and total psychosocial problems, in addition to significantly more impairment in all areas of health related quality of life.

CONCLUSIONS

Snoring in children with monosymptomatic nocturnal enuresis puts them at increased risk for behavioral and psychosocial problems, in addition to impaired health related quality of life. These findings support the need for future studies of the neurological links between sleep disordered breathing and monosymptomatic nocturnal enuresis.

Aberrant whole-brain functional connectivity and intelligence structure in children with primary nocturnal enuresis

AIM

To assess the potential relationship between intelligence structure abnormalities and whole-brain functional connectivity in children with primary nocturnal enuresis (PNE) with resting-state functional magnetic resonance imaging (fMRI) to provide insights into the association between these two seemingly unrelated conditions.

METHODS

Intelligence testing and fMRI data were obtained from 133 right-handed children, including 67 PNE children (M/F, 39:28; age, 10.5 ± 1.2 y) and 66 age-matched healthy controls (M/F, 37:29; age, 10.1 ± 1.1 y). All intelligence tests were performed using the China-Wechsler Intelligence Scale for Children (C-WISC). Each subject's full intelligence quotient (FIQ), verbal IQ (VIQ), performance IQ (PIQ), and memory/caution (M/C) factor was measured and recorded. Resting state fMRI scans were performed on a 3.0-T MR scanner and post-processed using REST software. Comparisons of z-score correlation coefficients between distinct cerebral regions were used to identify altered functional connectivity in PNE children.

RESULTS

The PNE group had normal FIQ, VIQ, and PIQ values, indicating no significant variation from the control group. However, the M/C factor was significantly lower in the PNE group. Compared to the control group, PNE children exhibited overall lower levels of functional connectivity that were most apparent in the cerebello-thalamo-frontal pathway. The M/C factor significantly correlated with z-scores representing connectivity between Cerebellum_Crus1_L and Frontal_Mid_R.

CONCLUSION

PNE children exhibit intelligence structure imbalance and attention deficits. Our findings suggest that cerebello-thalamo-frontal circuit abnormalities are likely to be involved in the onset and progression of attention impairment in PNE children.