Growth patterns in individuals with CDKL5 deficiency disorder.

AIM: To compare growth in individuals with cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder with population norms and to investigate the effect of gastrostomy on growth. METHOD: The longitudinal study included 353 individuals from the International CDKL5 Disorder Database with any anthropometric measurement in baseline and/or follow-up questionnaires. The British 1990 growth reference was used to determine the age- and sex-standardized z-score. Repeated cross-sectional data were fitted using a Gaussian linear regression model with generalized estimating equations. RESULTS: All growth parameters were below the general population norm (mean z-scores: weight -0.97, height -0.65, body mass index [BMI] -0.81, head circumference -2.12). The disparity was particularly pronounced for all anthropometric measurements after 4 years of age except for BMI. Moreover, individuals with gastrostomy placement were shown to have a larger decrease than those without. INTERPRETATION: In addition to weight, height, and BMI, head circumference was also compromised in this disorder. Microcephaly could be considered a helpful diagnostic feature, especially in adults. Any benefit of gastrostomy on weight and BMI was mainly seen in the early years.

Shoulder dystocia in babies born to Aboriginal mothers with diabetes: a population-based cohort study, 1998-2015.

BACKGROUND: Australian Aboriginal and Torres Strait Islander women with diabetes in pregnancy (DIP) are more likely to have glycaemic levels above the target range, and their babies are thus at higher risk of excessive fetal growth. Shoulder dystocia, defined by failure of spontaneous birth of fetal shoulder after birth of the head requiring obstetric maneuvers, is an obstetric emergency that is strongly associated with DIP and fetal size. The aim of this study was to investigate the epidemiology of shoulder dystocia in Aboriginal babies born to mothers with DIP. METHODS: Stratifying by Aboriginal status, characteristics of births complicated by shoulder dystocia in women with and without DIP were compared and incidence and time-trends of shoulder dystocia were described. Compliance with guidelines aiming at preventing shoulder dystocia in women with DIP were compared. Post-logistic regression estimation was used to calculate the population attributable fractions (PAFs) for shoulder dystocia associated with DIP and to estimate probabilities of shoulder dystocia in babies born to mothers with DIP at birthweights > 3 kg. RESULTS: Rates of shoulder dystocia from vaginal births in Aboriginal babies born to mothers with DIP were double that of their non-Aboriginal counterparts (6.3% vs 3.2%, p < 0.001), with no improvement over time. Aboriginal mothers with diabetes whose pregnancies were complicated by shoulder dystocia were more likely to have a history of shoulder dystocia (13.1% vs 6.3%, p = 0.032). Rates of guideline-recommended elective caesarean section in pregnancies with diabetes and birthweight > 4.5 kg were lower in the Aboriginal women (28.6% vs 43.1%, p = 0.004). PAFs indicated that 13.4% (95% CI: 9.7%-16.9%) of shoulder dystocia cases in Aboriginal (2.7% (95% CI: 2.1%-3.4%) in non-Aboriginal) women were attributable to DIP. Probability of shoulder dystocia among babies born to Aboriginal mothers with DIP was higher at birthweights > 3 kg. CONCLUSIONS: Aboriginal mothers with DIP had a higher risk of shoulder dystocia and a stronger association between birthweight and shoulder dystocia. Many cases were recurrent. These factors should be considered in clinical practice and when counselling women.

Genotype and sleep independently predict mental health in Rett syndrome: an observational study.

BACKGROUND: Rett syndrome is a genetically caused neurodevelopmental disorder associated with severe impairments and complex comorbidities. This study examined predictors of anxiety and depression in Rett syndrome, including genotype. METHODS: The International Rett Syndrome Database, InterRett, was the data source for this observational study. Associations between genotype, functional abilities, comorbidities, anxiety and depression were estimated with univariate and multivariate regression models. An additional regression model for anxiety included use of an anxiety medication as a predictor variable. RESULTS: The sample included 210 individuals aged 6-51 years of whom 54 (25.7%) were on psychotropic medication for anxiety or depression. Individuals with the p.Arg294* variant had the highest anxiety scores, as did those with insomnia or excessive daytime sleepiness, irrespective of anxiety medication use. Individuals with the p.Arg306Cys variant had the lowest depression scores, as did those with insomnia or excessive daytime sleepiness. CONCLUSION: Findings indicated that genotype and sleep have implications for mental health in Rett syndrome, suggesting that anticipatory guidance and proactive management of poor sleep could improve mental health. More research is needed to understand the effects of psychometric medications, which cannot be inferred from this cross-sectional study.

Hospitalizations from Birth to 28 Years in a Population Cohort of Individuals Born with Five Rare Craniofacial Anomalies in Western Australia.

OBJECTIVE: To describe trends, age-specific patterns, and factors influencing hospitalizations for 5 rare craniofacial anomalies (CFAs). METHODS: Data on livebirths (1983-2010; n = 721 019) including rare CFA (craniofacial microsomia, mandibulofacial dysostosis, Pierre Robin sequence, Van der Woude syndrome, and frontonasal dysplasia), episodes of death, and demographic and perinatal factors were identified from the Western Australian Register of Developmental Anomalies, Death Registrations and Midwives Notification System. Information on incident craniofacial and noncraniofacial related admissions, length of hospital stay, and intensive care and emergency-related admissions were identified using principal diagnosis and procedural codes were extracted from the Hospital Morbidity Data Collection and linked to other data sources. Associations of hospitalizations by age groups as well as demographic and perinatal factors were expressed as incidence rate ratio (IRR). RESULTS: The incident hospitalizations were 3 times as high for rare CFA (IRR 3.22-3.72) throughout childhood into adolescence than those without. Children with rare CFA had 3-4 times as many potentially preventable hospitalizations until 18 years of age than those without. Specifically, respiratory infections (IRR 2.13-2.35), ear infections (IRR 7.92-26.28), and oral health-related conditions contributed for most noncraniofacial admissions until the adolescence period. A greater incidence of noncraniofacial related hospitalizations was observed among Indigenous children, births with intrauterine growth restrictions, and families with high socioeconomic disadvantage. CONCLUSIONS: Throughout childhood, individuals with rare CFA had greater hospital service use, specifically for potentially preventable conditions, than those without. These population-level findings can inform new preventive strategies and early disease management targeted toward reducing preventable hospitalizations.

Can telehealth increase physical activity in individuals with Rett syndrome? A multicentre randomized controlled trial.

AIM: To evaluate the effects of a physical activity programme on sedentary behaviour and physical activity in ambulant individuals with Rett syndrome (RTT). METHOD: In this multicentre randomized waitlist-controlled trial, we recruited 43 ambulatory individuals with RTT in Australia and Denmark. Adequate baseline data were obtained from 38 participants (mean age 20 years, range 6-41, SD 10 years 6 months, one male). All completed the trial. Participants received 12 weeks of usual care (n = 19) or a goal-based, telehealth-supported programme in which activities occurred in their familiar environments (n = 19). Sedentary time and daily steps were assessed at baseline, post-test, and 12-week follow-up. The data analyst was blinded to group allocation. RESULTS: Sedentary time decreased in the intervention group by 2.7% (95% confidence interval [CI] -6.0 to 0.6) and increased in the control group by 1.3% (95% CI -4.8 to 7.4). Intervention and control groups increased the number of their steps per day by 264.7 (95% CI -72.2 to 601.5) and 104.8 (95% CI -178.1 to 387.7) respectively. No significant differences were found on any outcomes at post-test. There were three minor adverse events. INTERPRETATION: A goal-based telehealth intervention seemed to produce small improvements in physical activity for individuals with RTT. Families require more support to increase these individuals' extremely low physical activity levels. WHAT THIS PAPER ADDS: A telehealth-supported intervention may produce small changes in physical activity in Rett syndrome (RTT). Increasing physical activity in individuals with RTT is challenging for caregivers. Families require substantial out-of-home support to increase their children's activity levels.

Patterns, trends, and factors influencing hospitalizations for craniosynostosis in Western Australia. A population-based study.

Understanding hospital service use among children with a diagnosis of craniosynostosis (CS) is important to improve services and outcomes. This study aimed to describe population-level trends, patterns, and factors influencing hospitalizations for craniosynostosis in Western Australia. Data on live births (1990-2010; n = 554,624) including craniosynostosis, episodes of death, demographic, and perinatal factors were identified from the midwives, birth defects, hospitalizations, and death datasets. Information on craniosynostosis and non-craniosynostosis-related admissions, cumulative length of hospital stay (cLoS), intensive care unit, and emergency department-related admissions were extracted from the hospitalization dataset and linked to other data sources. These associations were examined using negative binomial regression presented as annual percent change and associations of hospitalizations by age groups, demographic, and perinatal factors were expressed as incidence rate ratio (IRR). We found an increasing trend in incident hospitalizations but a marginal decline in cLoS for craniosynostosis over the observed study period. Perinatal conditions, feeding difficulties, nervous system anomalies, respiratory, and other infections contributed to majority of infant non-CS-related admissions.Respiratory infections accounted for about twice the number of admissions for individuals with CS (IRRs 1.94-2.34) across all observed age groups. Higher incidence of non-CS hospitalizations was observed among females, with associated anomalies, to families with highest socioeconomic disadvantage and living in remote areas of the state.   Conclusion: Marginal reduction in the cLoS for CS-related admissions observed over the 21-year period are potentially indicative of improved peri-operative care. However, higher incidence of respiratory infection-related admissions for syndromic synostosis is concerning and requires investigation.

Oral parafunction and bruxism in Rett syndrome and associated factors: An observational study.

OBJECTIVES: To explore patterns of parafunction, and bruxism, and its relationships with genotype and snoring in individuals with Rett syndrome (RTT). METHODS: Retrospective observational data of those with confirmed MECP2 mutations in the InterRett database (n = 216) were used to investigate experience of parafunctional habits, and bruxism and their relationships with genotype and snoring using multivariable linear regression. RESULTS: The prevalence of parafunction was 98.2%. Bruxism was reported (66.2%) with the patterns mostly both diurnal and nocturnal (44.1%) and exclusively diurnal (42.7%). Compared to individuals with C-terminal deletion, individuals with p.Arg106Trp mutations were less likely to have bruxism reported (aOR = 0.15; 95% CI 0.02-0.98, p = 0.05) and those with p.Arg168* mutation were more likely to have frequent bruxism than none or occasional bruxism reported (aROR 3.4; 95% CI 1.1-10.7 p = 0.04). The relative odds of having nocturnal bruxism constantly, compared to none/occasionally, were higher among those 'always' snoring (aROR 6.24; 95% CI 2.1-18.2, p = 0.001) than those with no snoring. CONCLUSIONS: There appeared to be genotypic association with bruxism in p.Arg168* and p.Arg106Trp mutations and association between nocturnal bruxism and frequent snoring in an international sample of individuals with RTT. Clinical significance of the high prevalence of bruxism should be highlighted in relation to difficulty communicating pain and increased dental treatment need in RTT.

Epidemiology of Hospital Admissions for Craniosynostosis in Australia: A Population-Based Study.

To describe trends, age, and sex-specific patterns of population hospital admissions with a diagnosis of craniosynostosis (CS) in Australia.Population data for hospital separations (in-patient) from public and private hospitals (July 1996-June 2018) were obtained from the publicly available Australian Institute of Health and Welfare (AIHW) National Hospital Morbidity Database.The outcome variables were hospital separation rates (HSR) (number of hospital separations divided by the estimated resident population [ERP] per year) and average length of stay (aLOS) (patient days divided by the number of hospital separations) with a diagnosis of CS. Trends in HSR and aLOS adjusted for age, sex, and type of CS were investigated by negative binomial regression presented as annual percent change (APC).In 8057 admissions identified, we observed no significant change in the annual trend for HSR for the 22-year period. However, a marginal annual decrease of 1.6% (95% CI: -0.7, -2.4) in the aLOS was identified for the same time period. HSR were higher for males, infants, and single suture synostosis. aLOS was 3.8 days (95% CI: 3.8, 3.9) per visit, longer for syndromic conditions.There was a minor reduction in the average length of hospital stay for CS over the 22-year period potentially indicative of improved care. Population-level information on hospitalisations for rare craniofacial conditions can inform research, clinical, and surgical practice.

Epidemiology of Rare Craniofacial Anomalies: Retrospective Western Australian Population Data Linkage Study.

OBJECTIVE: To describe birth prevalence of rare craniofacial anomalies and associations with antenatal and perinatal factors. STUDY DESIGN: All live and stillbirths in Western Australia between 1980 and 2010 were identified from the Western Australian Birth Registrations and the Midwives Notification System (also provides information on antenatal and perinatal factors). Rare craniofacial anomalies (craniosynostosis, craniofacial microsomia, and others [Pierre Robin, Van der Woude, and Treacher Collins syndrome]) were ascertained from the Western Australian Register of Developmental Anomalies and linked to other data sources. Trends in prevalence, adjusted for sex and Indigenous status, were investigated by Poisson regression and presented as annual percent change (APC). Strengths of association of related factors were assessed using multivariable log-binomial regression adjusted for sex, Indigenous status, birth year, socioeconomic disadvantage, and remoteness and reported as risk ratios with 95% CIs. RESULTS: There was a temporal increase in prevalence of metopic synostosis (APC 5.59 [2.32-8.96]) and craniofacial microsomia (Goldenhar syndrome) (APC 4.43 [1.94-6.98]). Rare craniofacial anomalies were more likely among infants born preterm, as twins or greater-order multiples, with growth restriction, to older parents, to mothers undertaking fertility treatments, and with pre-existing medical conditions, specifically epilepsy, diabetes, or hypothyroidism. Prenatal identification of rare craniofacial anomalies was uncommon (0.6%). CONCLUSIONS: Our findings indicate a steady increase over time in prevalence of metopic synostosis and craniofacial microsomia (Goldenhar syndrome). Possible associations of fertility treatments and pre-existing maternal medical conditions with rare craniofacial anomalies require further investigation.

Influences on the trajectory and subsequent outcomes in CDKL5 deficiency disorder.

OBJECTIVE: The study investigated the effect of seizure and medication burden at initial contact with the International CDKL5 Disorder Database on subsequent development and clinical severity and compared quality of life among those whose development progressed, remained stable, or regressed between baseline and follow-up. METHODS: The effects of seizure and medication burden at baseline (high or low) on the CDKL5 Disorder Severity Scores and CDKL5 Developmental Score (CDS) at follow-up were assessed using linear and negative binomial regressions, respectively, with adjustment for age at baseline, gender, and follow-up duration with and without genotype. Seizure and medication burden were defined by average daily seizure count (high, ≥5/day; low, <5/day) and number of antiseizure medications (high, ≥3/day; low, <3/day), respectively. The effects of change in CDS over time (improved, stable, or deteriorated) on Quality of Life Inventory-Disability (QI-Disability) total and domain scores at follow-up were assessed in those aged at least 3 years at follow-up using linear regression models with adjustment for baseline CDS, gender, and follow-up duration. RESULTS: The expected follow-up CDS was lower for individuals with high compared to low seizure burden at baseline (ß = -.49, 95% confidence interval [CI] = -.84 to -.13). The average total QI-Disability score was 5.6 (95% CI = -.2 to 11.5) points higher among those with improved compared with stable or deteriorating CDS and 8.5 (95% CI = 3.1-13.8) points lower for those with deteriorating compared to stable or improved CDS. SIGNIFICANCE: Our finding that later development showed slight improvement in those with better earlier seizure control even after adjustment for genotype suggests that the trajectory for an individual child is not necessarily predetermined and could possibly be influenced by optimal seizure management. This has implications for children's quality of life.

Association between craniofacial anomalies, intellectual disability and autism spectrum disorder: Western Australian population-based study.

BACKGROUND: Accurate knowledge of the relationship between craniofacial anomalies (CFA), intellectual disability (ID) and autism spectrum disorder (ASD) is essential to improve services and outcomes. The aim is to describe the association between CFA, ID and ASD using linked population data. METHODS: All births (1983-2005; n = 566,225) including CFA births (comprising orofacial clefts, craniosynostosis, craniofacial microsomia and mandibulofacial dysostosis) surviving to 5 years were identified from the birth, death, birth defects and midwives population data sets. Linked data from these data sets were followed for a minimum of 5 years from birth until 2010 in the intellectual disability database to identify ID and ASD. These associations were examined using a modified Poisson regression. RESULTS: Prevalence of ID and ASD was higher among CFA (especially with additional anomalies) than those without [prevalence ratio 5.27, 95% CI 4.44, 6.25]. It was higher among CFA than those with other gastrointestinal and urogenital anomalies but lower than nervous system and chromosomal anomalies. Children with CFA and severe ID had a higher proportion of nervous system anomalies. CONCLUSIONS: Findings indicate increased ID and ASD among CFA but lower than nervous system and chromosomal anomalies. This population evidence can improve early identification of ID/ASD among CFA and support service planning. IMPACT: Our study found about one in ten children born with craniofacial anomalies (CFA) are later identified with intellectual disability (ID). Prevalence of ID among CFA was higher than those with other gastrointestinal, urogenital, and musculoskeletal birth defects but lower than those with the nervous system and chromosomal abnormalities. Most children with craniofacial anomalies have a mild-to-moderate intellectual disability with an unknown aetiology. On average, intellectual disability is identified 2 years later for children born with non-syndromic craniofacial anomalies than those with syndromic conditions. Our findings can improve the early identification of ID/ASD among CFA and support service planning.

Determinants of quality of life in Rett syndrome: new findings on associations with genotype.

BACKGROUND: Rett syndrome is a genetically caused neurodevelopmental disorder associated with functional deficits and comorbidities. This study investigated relationships between genotype, functional abilities and comorbidities and quality of life in Rett syndrome. METHODS: The International Rett Syndrome Database, InterRett, was used as a sampling frame for this observational study. Information was collected to describe functional abilities (walking and feeding), health (Sleep Disorder Scale for Children, the Rett Syndrome Behavioural Questionnaire), parental health (12-item Short Form Health Survey) sociodemographic factors (parental employment and education) and quality of life (Quality of Life Inventory-Disability) for 210 individuals with Rett syndrome. Univariate and multivariate regressions were used to analyse the relationships between the independent variables and quality of life. RESULTS: Compared with individuals with the p.Arg270* mutation, those with the p.Arg294* mutation type had the poorest quality of life (coeff -12.81, 95% CI -23.49 to 2.12), despite this being recognised as a clinically milder genotype. Overall better walking and feeding skills and seizure parameters were more associated with better quality of life and poor sleep and behavioural difficulties with poorer quality of life. CONCLUSIONS: These findings suggest that genotype, functioning and health each have implications for quality of life and should be considered when counselling families and planning clinical and support management strategies.

Trends and burden of diabetes in pregnancy among Aboriginal and non-Aboriginal mothers in Western Australia, 1998-2015.

BACKGROUND: Diabetes in pregnancy (DIP), which includes pre-gestational and gestational diabetes, is more prevalent among Aboriginal women. DIP and its adverse neonatal outcomes are associated with diabetes and cardiovascular disease in the offspring. This study investigated the impact of DIP on trends of large for gestational age (LGA) in Aboriginal and non-Aboriginal populations, and added to the limited evidence on temporal trends of DIP burden in these populations. METHODS: We conducted a retrospective cohort study that included all births in Western Australia between 1998 and 2015 using linked population health datasets. Time trends of age-standardised and crude rates of pre-gestational and gestational diabetes were estimated in Aboriginal and non-Aboriginal mothers. Mixed-effects multivariable logistic regression was used to estimate the association between DIP and population LGA trends over time. RESULTS: Over the study period, there were 526,319 births in Western Australia, of which 6.4% were to Aboriginal mothers. The age-standardised annual rates of pre-gestational diabetes among Aboriginal mothers rose from 4.3% in 1998 to 5.4% in 2015 and remained below 1% in non-Aboriginal women. The comparable rates for gestational diabetes increased from 6.7 to 11.5% over the study period in Aboriginal women, and from 3.5 to 10.2% among non-Aboriginal mothers. LGA rates in Aboriginal babies remained high with inconsistent and no improvement in pregnancies complicated by gestational diabetes and pre-gestational diabetes, respectively. Regression analyses showed that DIP explained a large part of the increasing LGA rates over time in Aboriginal babies. CONCLUSIONS: There has been a substantial increase in the burden of pre-gestational diabetes (Aboriginal women) and gestational diabetes (Aboriginal and non-Aboriginal) in recent decades. DIP appears to substantially contribute to increasing trends in LGA among Aboriginal babies.

Association between lack of dental service utilisation and caregiver-reported caries in Australian Indigenous children: A national survey.

AIM: To investigate the association between the lack of dental service utilisation and dental caries in Australian Indigenous children. METHODS: Data from the Longitudinal Study of Indigenous Children, which is a longitudinal population-based cross-sectional study in Australia were analysed. A total of 1258 children were included, consisting of the baby cohort and the child cohort at Wave 7. Logistic regression analysis was conducted to examine the association between caregiver-reported child dental caries and dental service utilisation. Multiple imputation using the fully conditional specifications approach was used to account for missing data. RESULTS: Around one tenth (12.3%) of Indigenous children did not see a dentist when required. Lack of dental service utilisation was associated with an increased likelihood of caregiver-reported dental caries (odds ratio (OR) 2.4; 95% confidence interval (CI) 1.5-3.8) and teeth removed due to dental caries (OR 2.3; 95% CI 1.1-4.7). These associations remained after adjusting for confounders (caregiver-reported dental caries OR 2.3; 95% CI 1.3-3.8; teeth removed due to dental caries OR 2.1; 95% CI 1.0-4.4). The reasons reported for not utilising dental services when required were the lack of an available dentist (31.4%), difficulties with physical access (19.8%), long waiting times (13.9%), financial issues with cost (5.8%) and feeling that 'they could cope' (4.6%). CONCLUSIONS: Lack of dental service utilisation was associated with dental caries and extraction due to caries in Australian Indigenous children.

Description of Total Population Hospital Admissions for Treacher Collins Syndrome in Australia.

OBJECTIVE: To describe patterns and demographic characteristics of total-population hospital admissions with a diagnosis of Treacher Collins syndrome (TCS) in Australia. DATA SOURCE: Population summary data for inpatient hospitals admissions (public and private) with a principal diagnosis of TCS (ICD10-AM-Q87.04) were obtained from the Australian Institute of Health and Welfare National Hospital Morbidity Database for a 11-year period (2002-2013). MAIN OUTCOME MEASURES: The primary outcome was hospital separation rate (HSR), calculated by dividing the number of hospital separations by estimated resident population per year. Trends in HSR s adjusted for age and sex were investigated by negative binomial regression presented as annual percent change and the association of rates with age and sex was expressed as incidence rate ratio. RESULTS: In 244 admissions identified, we observed an increase of 4.55% (95% confidence interval [CI] -1.78, 11.29) in HSR's over the 11-year period. Rates were higher during infancy (1.87 [95% CI 1.42, 2.42]), declining markedly with increasing age. The average length of hospital stay was 6.09 days (95% CI 5.78, 6.40) per episode, but longer for females and infants. CONCLUSIONS: Findings indicate an increase in hospitalization rates, especially among infants and females which potentially relates to early airway intervention procedures possibly influenced by sex specific-disease severity and phenotypic variability of TCS. Awareness of the TCS phenotype and improved access to genetic testing may support more personalized and efficient care. Total-population administrative data offers a potential to better understand the health burden of rare craniofacial diseases.

Longitudinal Evaluation of the Stability of Hand Function in Rett Syndrome.

OBJECTIVE: To investigate the longitudinal stability of hand function in Rett syndrome and to analyze further the relationships between stability of hand function and genotype, age, and walking ability. STUDY DESIGN: Longitudinal video data of functional abilities of individuals with genetically confirmed Rett syndrome were collected by families of individuals registered with the Australian Rett Syndrome Database. A total of 120 individuals provided 290 recordings from which 170 observation pairs were available for comparison. The Rett Syndrome Hand Function Scale was used to classify a level of hand function observed in each video on a range from unable to grasp, pick up, and hold objects to skillful manipulation of large and small objects. RESULTS: Approximately one-third of the population lost some hand function over time. Younger children (<6 years) rather than adults were at greater risk of deterioration in hand function. Clinical severity, as indicated by walking ability or genotype, played a lesser role. There was no identified pattern between genotype and the stability of hand function skills. Rather, mutations associated with milder (p.Arg133Cys, p.Arg294∗) and greater (p.Arg106Trp, p.Thr158Met) clinical severity were both associated with greater risks of decline. CONCLUSIONS: Genotype was a lesser predictor of loss of hand function beyond the early regression period, and younger children were particularly vulnerable to further loss of hand function compared with adults.

Exploring genotype-phenotype relationships in the CDKL5 deficiency disorder using an international dataset.

Characterized by early-onset seizures, global developmental delay and severe motor deficits, CDKL5 deficiency disorder is caused by pathogenic variants in the cyclin-dependent kinase-like 5 gene. Previous efforts to investigate genotype-phenotype relationships have been limited due to small numbers of recurrent mutations and small cohort sizes. Using data from the International CDKL5 Disorder Database we examined genotype-phenotype relationships for 13 recurrent CDKL5 variants and the previously analyzed historic variant groupings. We have applied the CDKL5 Developmental Score (CDS) and an adapted version of the CDKL5 Clinical Severity Assessment (CCSA), to grade the severity of phenotype and developmental outcomes for 285 individuals with CDKL5 variants. Comparisons of adapted CCSA and CDS between recurrent variants and variant groups were performed using multiple linear regression adjusting for age and sex. Individuals with the missense variant, p.Arg178Trp, had the highest mean adapted CCSA and lowest mean developmental scores. Other variants producing severe phenotypes included p.Arg559* and p.Arg178Gln. Variants producing milder phenotypes included p.Arg134*, p.Arg550*, and p.Glu55Argfs*20. There are observed differences in phenotype severity and developmental outcomes for individuals with different CDKL5 variants. However, the historic variant groupings did not seem to reflect differences in phenotype severity or developmental outcomes as clearly as analyzed by individual variants.

Decline in gross motor skills in adult Rett syndrome; results from a Danish longitudinal study.

Longevity of individuals with neurodevelopmental diseases as Rett syndrome (RTT) has increased and many reach adulthood and old age. There is therefore a need to increase knowledge about the course of RTT in adults in order to improve medical care management and quality of life. We did a longitudinal study to address if a possible decline in motor skills in adults with RTT can be explained by the presence of common medical conditions as epilepsy, breathing disturbance, and scoliosis. Data from the Danish RTT database, medical files, and videos from visits at the national Center for Rett syndrome were reviewed. The study included 24 individuals aged 30-66 years at last visit after a follow-up period of 6-12 years. Results showed a clinically observable and significant decline in gross motor skills using the Rett syndrome Gross Motor Scale (RSGMS) with a tendency of less decline in the individuals with the best motor abilities. The frequencies of comorbidities were high. Decline in RSGMS score was associated with the presence of epilepsy and severe scoliosis that had been conservatively managed. The results emphasize that epilepsy plays a significant role in the adult RTT life and management of severe scoliosis in the younger years has impact on the motor abilities in adulthood.

The perceived effects of cannabis products in the management of seizures in CDKL5 Deficiency Disorder.

INTRODUCTION: CDKL5 Deficiency Disorder (CDD) is a severe treatment-resistant form of early-onset epilepsy. Current treatment options are often ineffective and associated with adverse effects, forcing families to seek alternative therapies for their children including products derived from cannabis. Reportsof miraculous cures and a public preferencefor 'natural' therapies have resulted in considerable public interest, and so this study aimed to characterize the use of cannabis in these individuals, as well as compare caregiver perceptions of efficacy and safety to objective evidence of seizure control and number of antiepileptic drugs used. METHODS: Families from the International CDKL5 Disorder Database were invited to complete questionnaires which included data relating to their child's current and past treatments, including use of any cannabis-derived preparations. Perceived effects on seizure control, as well as additional benefits and adverse effects were reported. Seizure frequency and number of antiepileptic drugs were compared between those actively using cannabis products and those who were not. Longitudinal analysis was performed on a subset of the study population to compare these same variables at pre-treatment and post-treatment time points. RESULTS: Three hundred and twelve caregivers answered questions regarding their child's use of antiepileptic medications. Of these, 82 (26%) described use of cannabis preparations either at present, or in the past, with the most common being cannabidiol. Of 70 caregivers that described their perceived effect on seizure control, more than two thirds reported an improvement in seizure control, either temporary (16%) or lasting (54%). Additional benefits included improvements in attention, cognition, and sleep. The majority of responses (78%) described adverse effects as 'none', though some reported an increase in sedation and gastrointestinal upset. There was no reduction in the median seizure frequency nor the number of different antiepileptic drugs, for those who were actively using cannabis products compared to those who were not. Similarly, individuals who were not using cannabis products at an initial time point had no differences in seizure frequency nor number of antiepileptic drugs at a second timepoint when they had started using this treatment. CONCLUSIONS: Although this is an observational study, limited by potential participation bias and the unreliable nature of unblinded self-assessment, it suggests that caregivers perceive cannabis products, especially cannabidiol, to have a tolerable adverse effect profile and adequate efficacy. Despite this, cannabis was not associated with a reduction in seizure frequency nor number of antiepileptic drugs when compared to non-users or when compared to pre-treatment. Randomized controlled trials are urgently needed to more reliably assess this treatment's safety and efficacy.

Gestational age as a predictor for subsequent preterm birth in New South Wales, Australia.

BACKGROUND: There is no validated evidence base on predictive ability and absolute risk of preterm birth by gestational age of the previous pregnancy. METHODS: We conducted a retrospective cohort study of mothers who gave birth to their first two children in New South Wales, 1994-2016 (N = 517,558 mothers). For each week of final gestational age of the first birth, we calculated relative and absolute risks of subsequent preterm birth. RESULTS: For mothers whose first birth had a gestational age of 22 to 30 weeks the absolute risks of clinically significant preterm second birth (before 28, 32, and 34 weeks) were all less than 14%. For all gestational ages of the first child the median gestational ages of the second child were all at least 38 weeks. Sensitivity and positive predictive values were all below 30%. CONCLUSION: Previous gestational age alone is a poor predictor of subsequent risk of preterm birth.