The influence of ethnicity and glucose tolerance status on subjective hunger sensations and prospective food intake in overweight and obese Asian and European Australians.

AIMS: To examine the influence of ethnicity and glucose tolerance status on subjective sensations and food intake in overweight/obese Asian and European Australians. METHODS: 18 Asians and 26 Europids were classified as normal glucose tolerance (NGT) and impaired glucose tolerance (IGT) based on serial measures of finger-prick glucose following an oral glucose tolerance test (OGTT). Subjective sensations of hunger and satiety were measured before and every 15min after the OGTT using a visual analogue scale (VAS). Food intake was measured covertly from consumption of a buffet style lunch and from self-maintained 24h food records. All serial measurements were converted into total area under the curve (TAUC) and comparisons adjusted for age, fat and fat-free mass. RESULTS: There was a significant difference interaction between ethnicity (ETH) and glucose tolerance (GTT) for subjective fullness, desire for food and prospective food intake. IGT Asians had significantly greater sensations of fullness, but lesser prospective food and desire to eat, as compared to other groups. However there were no differences in calorie and macronutrient intake at buffet lunch or over 24-h. CONCLUSION: Interactions between ethnicity and glucose tolerance status in subjective sensations did not transcribe to differences in prospective food intake.

Feeding experiences and growth status in a Rett syndrome population.

OBJECTIVES: Feeding difficulties in Rett syndrome are complex and multifactorial. In this study, we describe the feeding experiences in Rett syndrome and examine the factors affecting growth. MATERIALS AND METHODS: Using questionnaire data related to a population-based cohort, ages 2 to 29 years (n = 201), we measured the feeding experiences, growth, and factors affecting growth (enteral nutritional support, mutations, mobility, breath-holding, hyperventilation) in subjects with Rett syndrome. RESULTS: The mean weight, height, and body mass index z scores in subjects with Rett syndrome were below that of their age group and decreased steadily with age. Twenty percent of subjects had enteral nutrition support, and it was more common in the older age group. Those with truncating mutations had significantly less enteral nutrition support than the other mutation groups. Furthermore, those with low mobility had lower mean body mass index z scores than those with higher mobility, and increased frequency of breath-holding and hyperventilation also was associated with lower body mass index z scores. CONCLUSIONS: Routine monitoring of growth should continue to determine the severity of nutritional problems in Rett syndrome. Active nutritional management is recommended to ensure females affected with Rett syndrome have the best opportunity to reach their growth potential.

Predictors of scoliosis in Rett syndrome.

Scoliosis is a common clinical manifestation of Rett syndrome, a neurodevelopmental disorder that almost exclusively affects girls. Following apparently normal development, these girls typically regress and lose previously attained cognitive, social, and motor skills. Severe intellectual and physical disabilities remain throughout life. Mutations in the methyl-CpG-binding protein 2 gene, MECP2, are detected in approximately 80% of cases and are associated with phenotypic variability. Population-based data on Australian cases were used to study the association between early developmental and genetic factors and the onset of scoliosis. The median age at scoliosis onset was 9.80 years, and three quarters of subjects had developed scoliosis by 13 years of age. Children with compromised early development before 6 months, those who were less mobile at 10 months, and those who never walked were more likely to have an earlier onset of scoliosis. When seven common point mutations and large genomic and C-terminal deletions were compared, the R294X mutation appeared to provide some protective effect against the development of scoliosis.

Genotype and early development in Rett syndrome: the value of international data.

BACKGROUND: Rett syndrome is a neurodevelopmental disorder mostly affecting females and caused by mutations in the MECP2 gene. Originally the syndrome was characterised as having a normal prenatal and perinatal period with later regression. Previous work has speculated that the girl with Rett syndrome may not be normal at birth. AIMS: to examine whether early development between birth and ten months varies by genotype in Rett syndrome. METHODS: cases were sourced from two databases, the Australian Rett Syndrome Database (est. 1993) and the newly formed InterRett - IRSA Rett Phenotype Database. Data available on 320 cases included information provided by parents on perinatal problems, early developmental behaviour and mobility. Problem scores, mobility scores and a total composite score for each mutation were generated and compared. RESULTS: overall, 58% of respondents noted unusual behaviour during the first six months and 70.6% from the period between 6 and 10 months of life. Statistically significant differences were detected between some of the common mutations. Infants with R294X (P=0.05) and R133C (P=0.03) were less likely than those with R255X to have problems in the perinatal period. The most severe profile overall for early development was associated with mutations R255X and R270X. CONCLUSION: This is the largest study to date examining the effects of individual mutations in Rett syndrome. With the ongoing case ascertainment and expansion of InterRett, sample size will increase rapidly and provide improved statistical power for future analyses. Results from this study will contribute to understanding the mechanism of early development in Rett syndrome and determining if and at which time(s) early intervention might be feasible.

InterRett and RettBASE: International Rett Syndrome Association databases for Rett syndrome.

In 2001, the International Rett Syndrome Association funded the establishment of a World Wide Web-based database to collect and display the genetic data of children and adults with Rett syndrome from around the world. RettBASE () encompasses both published and unpublished data; includes pathogenic mutations, benign polymorphisms, and sequence variations of uncertain significance; and has a range of query capabilities, allowing for simple or complex interrogation of the database. To undertake genotype-phenotype correlations and to identify the likely subtle differences in phenotype, detailed phenotype data on large samples will be provided by the International Rett Syndrome Association International Phenotype database InterRett. InterRett is under development by the Australian Rett syndrome study group at the Telethon Institute for Child Health Research in Perth, Western Australia. It will collect data from clinicians and families and provide deidentified, collated data on the Internet (). Data records will be linked with RettBASE through a common unique identifier. An international reference panel is advising on the development of the database. Data collection procedures from families and clinicians are currently being piloted. Full data collection from both groups began in the second half of 2003. Concurrently, the output database will be developed to provide deidentified individual records and collated data for clinicians and researchers and collated data for families and the general public. This Web-based database will be an invaluable resource for understanding the nature of the disorder and managing children and adults with Rett syndrome.

Hand preference, extent of laterality, and functional hand use in Rett syndrome.

Residual hand use in functional tasks, extent of laterality, and right or left preference were studied in 145 2- to 24-year-old, postregression Australian subjects with Rett syndrome via parent questionnaire. Hand use was markedly restricted, more for complex than simple and for external (touching food and objects) than internal tasks (scratching, rubbing eyes), suggesting a deficit in cerebral control of external, goal-oriented hand use, which is perhaps genetically determined because there is significantly greater restriction of external tasks in subjects with demonstrated MECP2 mutations. Overall, 33.6% of patients were reported with a left-hand preference, 40.7% with a right-hand preference, and 25.7% with an equal hand preference. Extent of laterality was greater for external than internal and for complex than simple external tasks. Older subjects showed less functional hand use and possibly more overall laterality. However, their hand preference was similar to younger subjects. The anomalous pattern of hand preference in Rett syndrome may be linked to the primary apraxic deficit in this disorder rather than to late manifestation of laterality.