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Research Notes: PWS Abstracts - 1999[ 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 | 1999 | 1998 | 1997 | 1996 | 1995 | 1994 | 1993 | 1992 | 1991 | 1990 | 1980-1989 | 1979 and prior ] Acta Paediatr Suppl. 1999 Dec. Diabetes mellitus is becoming a more frequently recognized complication of Prader-Willi syndrome. It has been reported that as many as 7-20% of individuals with Prader-Willi syndrome may develop this complication. Diabetes mellitus adds to the complexity of an already complex treatment program, causes many serious complications that greatly affect the quality of life of these individuals, and can lead to serious morbidity and mortality. Recent studies suggest that growth hormone (GH) might offer significant advantages to individuals with Prader-Willi syndrome. However, as a known diabetogenic agent, GH might also increase the propensity to develop diabetes mellitus. For this reason, the characteristics of the diabetes mellitus that develops in individuals with Prader-Willi syndrome must be studied and fully understood. The initial assumption has been that the diabetes mellitus associated with this syndrome is identical to that seen in obese individuals without Prader-Willi syndrome, in whom genetic factors and obesity lead to insulin resistance. Severe insulin resistance in turn leads to pancreatic failure and hence the symptom complex of type 2 diabetes mellitus. To determine if this same pattern is present in patients with Prader-Willi syndrome, we evaluated both obese children and adults with the syndrome. These patients were compared with obese individuals without Prader-Willi syndrome matched for age, gender and weight and who had not yet developed diabetes but had equally longstanding obesity. We compared the glucose and insulin responses of these two groups, using both oral and intravenous glucose challenges. The results demonstrated that individuals with Prader-Willi syndrome do not show the predicted insulin resistance that is seen in obese children without the syndrome. In fact, the individuals with Prader-Willi syndrome showed normal or increased insulin sensitivity. These data do not support the hypothesis that the high incidence of diabetes mellitus in patients with Prader-Willi syndrome is simply the result of obesity and therefore suggest a different aetiology. Acta Paediatr Suppl. 1999 Dec. The authors have followed 18 prepubertal children (3-12 years of age) with Prader-Willi syndrome during 5 years of growth hormone (GH) treatment. Initially, all the children participated in a randomized, controlled GH trial, conducted to assess the effects of GH treatment on growth, body composition and behaviour. GH was administered to group A (n = 9) at a dose of 0.1 IU/kg/day (0.033 mg/kg/day) for 2 years. Group B (n = 9) was untreated for the first year, but the children were given GH at a dose of 0.2 IU/kg/day (0.066 mg/kg/day) during the second year. Thereafter, all children stopped GH treatment for 6 months and were then restarted with GH at a dose of 0.1 IU/kg/day (0.033 mg/kg/day). During the first year of GH treatment, there was a dramatic increase in height SDS in both groups. The attained height percentile was maintained during the continued GH treatment. Five years after the start of GH treatment, mean height SDS is still above average for age. Four children have reached final height, all within 2 SD of target height. During the first year of GH treatment, body mass index (BMI) SDS decreased significantly from 3.0 to 1.5 SDS in group A and from 2.8 to 1.2 SDS in group B, but it increased again during the 6-month period without treatment. Following the restart of GH treatment, BMI SDS has stabilized at 1.7 SDS for group A and 2.5 SDS for group B. In 16 of 18 patients, fasting insulin, glucose and the A1c fraction of glycosylated haemoglobin remained within normal ranges during 5 years of GH treatment. Following a period of rapid weight gain, two children have developed non-insulin-dependent diabetes mellitus. Glucose homeostasis returned to normal when GH treatment was withdrawn. In conclusion, GH treatment has a proven favourable effect on growth and body composition in patients with Prader-Willi syndrome. Treatment should be individualized, and close surveillance of glucose homeostasis is needed, especially if the patient is severely obese. Biomed Pharmacother. 1999 Dec. Diabetes mellitus is not a diagnostic criterion for Prader-Willi syndrome (PWS), but it is often found in PWS patients. The etiology for diabetes mellitus in PWS may be related to the morbid obesity and consequent insulin resistance, because a decrease of oxytocin neurons and leptin resistance in PWS may cause hyperphagia, inducing obesity. However, treatment with growth hormone (GH) is beneficial for the majority of GH-deficient PWS children, because relative decreased fat mass and increased fat-free mass could prevent obesity and concomitant insulin resistance. Hypogonadism is thought to be due to hypogonadotrophic hypogonadism in a majority of PWS patients. Hypergonadotrophic hypogonadism secondary to cryptorchidism and its treatment is shown in other cases. Low luteinizing hormone and high follicle-stimulating hormone levels in PWS cases in young men with idiopathic oligospermia or in the early stages of puberty is less frequently reported. J Pediatr Ophthalmol Strabismus. 1999 Nov-Dec. PURPOSE: Prader-Willi syndrome (PWS) refers to a genetic disorder induced by an anomaly on chromosome 15 occurring with a frequency of one in 10,000 to 20,000. It is characterized by a unique set of features including infantile hypotonia, obesity in childhood, small hands and feet, hypogonadism, and mental retardation. Reported here are the results of ophthalmic examinations of persons with PWS, together with results from controls comparable in age, percentage of body fat, and intelligence. These data bear on the hypothesis that the ocular anomalies in PWS are unique to this syndrome. METHOD: A comprehensive investigation of PWS brought children and adults to Vanderbilt University for extended testing, which included an ophthalmic examination. Genetic analysis determined unequivocally the PWS diagnosis and identified subgroups-deletion and maternal disomy. A group of persons without PWS but generally comparable in age, body composition, and intelligence served as controls. RESULTS: Significant differences between the deletion and disomy subgroups were not found for the clinical ophthalmic measures. The incidence of anomalies in the combined PWS was similar to those reported in previous studies. A similar pattern was present in the control group except for myopia and stereopsis. An effect of genetic subgroup, however, was observed for random element stereopsis with the maternal disomy group having a greater degree of impairment. CONCLUSION: The overall similarity between the PWS and control groups on all measures except myopia and stereopsis suggest that many of the anomalies in PWS found in prior studies are due to factors inherent in a general dysfunctional population, rather than reflective of an ocular signature unique to PWS. Eur J Pediatr. 1999 Nov. We studied whether the beneficial effects of growth hormone (GH) treatment on growth and body composition in PWS are accompanied by an improvement in respiratory function. We measured resting ventilation, airway occlusion pressure (P(0.1)) and ventilatory response to CO(2) in nine children, aged 7-14 years, before and 6-9 months after the start of GH treatment. During GH treatment, resting ventilation increased by 26%, P(0.1) by 72% and the response to CO(2) by 65% (P < 0.002, <0.04 and <0.02, respectively). This observed increase in ventilatory output was not correlated to changes in body mass index. Conclusion: Treatment of children with Prader-Willi syndrome (PWS) seems to have a stimulatory effect on central respiratory structures. The observed increase in ventilation and inspiratory drive may contribute to the improved activity level reported by parents of PWS children during growth hormone therapy. Eur J Pediatr. 1999 Nov. Abnormal ventilatory control in patients with Prader-Willi syndrome when awake and sleeping include abnormal responses to hyperoxia, hypoxia and hypercarbia. Lindgren et al., report similar results regarding response to hypoxia; however, they have demonstrated significant minute ventilation and carbon dioxide responses in their patients treated with growth hormone irrespective of body mass index. It is possible that the explanation for the abnormal respiratory control in this syndrome is located in central rather than peripheral structures. The hypothalamus stands out as the possible location that links their abnormal ventilatory control with the other features. Further investigations to correlate this finding are warranted. Acta Paediatr. 1999 Nov. No abstract available. J Intellect Disabil Res. 1999 Oct. The present authors describe sleep problems, including sleep apnoea and excessive daytime sleepiness (EDS), in subjects with Prader-Willi syndrome (PWS). The present paper reports a questionnaire study regarding sleep and behaviour in a group of 29 subjects with PWS, compared with an age- and gender-matched control group. Those with PWS suffered from sleep problems more frequently than the control subjects. Problems included EDS, snoring and early waking. Sleep problems in PWS were not associated with body mass index or weight. Excessive daytime sleepiness was a distinctive feature of the group with PWS, and behavioural disturbance in PWS children and adolescents was associated with EDS. Excessive daytime sleepiness seems to be characteristic of PWS, and may be related to problems with the sleep-wake cycle and hypothalamic dysfunction. J Am Acad Child Adolesc Psychiatry. 1999 Jun. OBJECTIVE: To analyze (1) which behavior and personality characteristics in Prader-Willi syndrome (PWS) are primarily linked to the syndrome and not to mental retardation or being overweight, (2) how early in life such traits appear, and (3) whether current therapies affect behavior. METHOD: Parents of a group of 44 individuals with PWS and of a comparison group were interviewed and completed questionnaires about their children's behavior and personality. RESULTS: Individuals with PWS had more behavior problems than those in the comparison group. Some behaviors were specific to PWS. Younger PWS cases had fewer behavior problems than older PWS cases. Treated individuals had approximately the same degree of behavior problems as those untreated, even though a few symptoms occurred at lower rates. CONCLUSIONS: PWS is associated with behavior correlates that are not related to weight or IQ. In the first few years of life, children with PWS do not demonstrate the characteristic profile of preoccupation with food, ritualism, irritability, temper tantrums, and skin-picking which is typical of older individuals with PWS. Current therapies (including treatment with growth hormone) do not seem to radically affect the behavioral expression of the disorder, even though some problems tended to abate with treatment. J Am Acad Child Adolesc Psychiatry. 1999 Mar. OBJECTIVE: To compare obsessive-compulsive (OC) symptoms in patients with Prader-Willi syndrome (PWS) and symptoms in a group of patients presenting with "Prader-Willi-like" features but without the genetic abnormalities associated with PWS. METHOD: 16 patients aged 4 through 20 years were evaluated in a clinic specializing in the assessment and management of behavioral and food-related problems in PWS. Eight patients were found to have key features of the syndrome but did not have a PWS genotype. These PWS-like subjects were matched to 8 clinic patients with a confirmed deletion of the PWS critical region of the paternally derived chromosome 15. All subjects were evaluated for obesity, IQ, food-related problems, maladaptive behaviors, and non-food-related OC symptoms. RESULTS: There were no differences between the 2 groups with respect to measures of obesity, IQ, food-related difficulties, or overall maladaptive behaviors. The PWS group showed significantly greater numbers of OC symptoms and greater symptom severity. CONCLUSIONS: Patients with PWS have elevated numbers of OC symptoms and significant symptom-related impairment which are not explained by developmental delay, food-related difficulties, or obesity. OC symptoms are part of a behavioral phenotype that accompanies deletions on the proximal long arm of chromosome 15 in PWS. J Pediatr. 1999 Feb. Body composition and leptin were studied in 13 young, still underweight and 10 older overweight children with Prader-Labhart-Willi syndrome. Not only the older overweight children but also the young underweight children had elevated skinfold standard deviation scores for body mass index and elevated body mass index adjusted leptin levels, suggesting relatively increased body fat despite underweight. Our data indicate that body composition in Prader-Labhart-Willi syndrome is disturbed already in infancy, long before the onset of obesity. Leptin production appears to be intact. Am J Ment Retard. 1999 Jan. Maladaptive behavior was compared across 23 people with Prader-Willi syndrome due to paternal deletion to 23 age- and gender-matched subjects with maternal uniparental disomy. Controlling for the higher IQs of the uniparental disomy group, deleted cases showed significantly higher maladaptive ratings on the Child Behavior Checklist's Internalizing, Externalizing, and Total domains as well as more symptom-related distress on the Yale-Brown Obsessive-Compulsive Scale. Across both measures, deleted cases were more apt to skin-pick, bite their nails, hoard, overeat, sulk, and withdraw. A dampening of symptom severity is suggested in Prader-Willi syndrome cases due to maternal uniparental disomy. Findings are compared to Angelman syndrome, and possible genetic mechanisms are discussed, as are implications for Prader-Willi syndrome and obsessive-compulsive behaviors. Horm Res. 1999. Insulin and glucose homeostasis have been studied during growth hormone (GH) treatment in 19 prepubertal children with Prader-Willi syndrome (PWS) and compared with 11 healthy prepubertal obese children. Before treatment, insulin levels in children with PWS were lower (p < 0.01) than in healthy obese children. During GH treatment, fasting insulin levels increased in children with PWS (p < 0.001). Glucose levels were similar for PWS and obese children before treatment. Children with PWS showed a slow glucose disappearance rate (k = 1.7%) which deteriorated (k = 1.3%, p < 0.001) during GH treatment. HbA1c and fasting glucose levels remained normal. Thus, GH treatment of children with PWS resulted in increased insulin blood levels, unchanged fasting glucose and HbA1c but decreased glucose elimination rate after an intravenous glucose test. However, the observed dose-dependent increase in insulin levels during GH treatment, that reached supranormal concentrations in 6/19 patients, and the occurrence of NIDDM [non-insulin dependent diabetes mellitus] in 1 patient during follow-up suggest that close surveillance and low doses of GH should be applied, especially if the PWS patient is very obese. Am J Perinatol. 1999. We describe a unique case of a newborn with Prader-Willi syndrome who presented with fetal goiter as well as neonatal thyroid abnormalities, marked hypotonia, and thrombocytopenia. These new clinical observations may correlate with the uniparental monodisomy form of inheritance of this genetic condition. [ 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 | 1999 | 1998 | 1997 | 1996 | 1995 | 1994 | 1993 | 1992 | 1991 | 1990 | 1980-1989 | 1979 and prior ] |