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Research Notes: PWS Abstracts - 1998[ 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 | 1999 | 1998 | 1997 | 1996 | 1995 | 1994 | 1993 | 1992 | 1991 | 1990 | 1980-1989 | 1979 and prior ] Biol Psychiatry. 1998 Dec 15. Background: The behavioral phenotype of Prader-Willi syndrome (PWS) suggests hypothalamic dysfunction and altered neurotransmitter regulation. The purpose of this study was to examine whether there was any difference in the concentrations of monoamine metabolites in the cerebrospinal fluid (CSF) in PWS and non-PWS comparison cases. Methods: The concentration of monoamine metabolites in CSF was determined in 13 children and adolescents with PWS diagnosed on clinical and genetic criteria. The concentrations were compared with those from 56 comparison cases in healthy and other contrast groups. Results: The concentrations of dopamine and particularly serotonin metabolites were increased in the PWS group. The differences were most prominent for 5-hydroxyindoleacetic acid [the main serotonin metabolite]. The increased concentrations were found in all PWS cases independently of age, body mass index, and level of mental retardation. Conclusions: The findings implicate dysfunction of the serotonergic system and possibly also of the dopamine system in PWS individuals, and might help inform future psychopharmacologic studies. J Intellect Disabil Res. 1998 Dec. The psychiatric symptomatology of people with Prader-Willi syndrome (PWS) has mainly been described in case reports and some large-scale descriptive studies. Unfortunately, there is still no systematic description of all the psychiatric symptoms which accompany this chromosomal error. Symptoms of mood disorder and anxiety dominate the picture of PWS, although some reports also mention psychotic symptoms with variations in prevalence of between 15% and 60%. The present paper presents six case reports of adult male subjects with a diagnosis of PWS and psychiatric symptoms who fulfill the criteria for cycloid psychosis (ICD-10 F.23.0). This psychotic disorder requires a specific psychopharmacological approach with mood stabilizing agents, particularly Lithium. It is concluded that subjects with PWS may be especially vulnerable to the development of cycloid psychosis, which suggests the existence of a specific 'psychopathological phenotype'. J Intellect Disabil Res. 1998 Dec. Previous studies have demonstrated that maladaptive behaviours are common amongst adults with Prader-Willi syndrome (PWS). Case reports have also previously demonstrated that psychosis can occur amongst adults with PWS. The present study was undertaken in order to gain a better understanding of the psychopathology of the psychosis of PWS. Twenty-three out of 25 adults identified with PWS living in Northamptonshire, UK, agreed to participate. Comprehensive psychiatric assessments (using the PPS-LD), and measures of adaptive and maladaptive behaviours (using the AAMR-ABS) were completed. Comparisons were made for the prevalence of psychiatric disorders against those from a previous epidemiological study of adults with intellectual disability of other aetiologies from a neighbouring county. The PWS group was found to have higher rates of affective disorders (a point prevalence of 17.4%), in which psychotic symptoms were common, but similar rates of schizophrenia/delusional disorders (4.3%) compared with the comparison group. Behaviour disorders were also common. Surprisingly, none of the PWS group was found to have generalized anxiety or phobic disorders. The diagnostic criteria for the episodes including psychotic symptoms are explored. The high rates of affective disorders is of clinical (i.e. treatment) importance as well as being of academic interest with regard to the genetics of psychiatric disorders. J Intellect Disabil Res. 1998 Dec. Six people with Prader-Willi syndrome (PWS) who developed psychoses are described. Along with other literature reviewed in the present paper, the results imply an association between PWS and psychotic symptoms. Genetic studies were possible in five cases and SNRPN expression was examined in three cases. Maternal uniparental disomy and 15q11q13 deletions were found, demonstrating that psychotic symptoms are not associated with a single type of genetic abnormality. J Intellect Disabil Res. 1998 Dec. The Psychopathology Assessment Schedule for Adults with Developmental Disability (PAS-ADD) checklist was used to screen for psychotic symptoms among people with Prader-Willi syndrome (PWS) aged 16 years and over. The scoring instructions for the PAS-ADD checklist were modified to take account of knowledge about the behavioural phenotype of PWS. Using modified scoring, 6.3% of the 95 people for whom checklists were completed had a possible psychotic disorder in the month before the assessment was made. The results should be treated as a crude estimate of the prevalence of psychotic symptoms associated with PWS in adult life in view of potential biases in the sample reported. These findings lend some support to the hypothesis that PWS has a non-chance association with psychotic symptoms and that the association is not entirely accounted for by the increased prevalence of psychosis associated with intellectual disability. Neurophysiol Clin. 1998 Dec. The association of Prader-Willi-syndrome with breathing disturbances such as sleep apnea syndrome and/or hypoxemia during REM sleep, REM sleep abnormalities and excessive daytime sleepiness is well known. We report the case of an 11-year-old boy who presented with Prader-Willi syndrome, obesity (body mass index [BMI] = 45.6), severe obstructive sleep apnea syndrome and significant daytime sleepiness on multiple sleep latency test. Behavioral disorders did not allowed the use of continuous positive pressure in this patient. Therefore, clomipramine (20 mg per day) was administered. Sleep examination over 8 months showed: slight weight loss (BMI = 44.4), persistence of severe obstructive sleep apnea syndrome, slight improvement in nocturnal hypoxemia, and disappearance of excessive daytime drowsiness with mean sleep latency of 15 min 37 s (less than 2 min before treatment) and no diurnal REM sleep periods. However, clomipramine had no effect on hyperphagia. J Intellect Disabil Res. 1998 Dec. The presence and severity of compulsive behaviours may be evaluated via the Compulsive Behaviour Checklist (CBC) and this instrument has been successfully employed in people with intellectual disability. However, the applicability of the overall CBC scoring system, which entails tallying the number of behavioural categories represented (i.e. five) as well as the number of individual behaviours endorsed (i.e. 25), is not known in the population with Prader-Willi syndrome (PWS). The present investigation examined the latent variable structure of the CBC in people with PWS in order to identify possible population-specific scoring and interpretation considerations. The 25 behaviour-specific items of the CBC were analysed for 75 people with PWS (44 females and 31 males) aged between 4 and 41 years (mean +/- SD = 11.4+/-9.4) via factor analysis with principal component extraction and equamax rotation. The most suitable solution was determined on the basis of multiple empirical criteria: (1) the scree test; (2) eigenvalues >1.00; (3) salient loadings >0.30; (4) the clarity of item assignment to a single latent dimension; (5) the internal consistency of the latent dimension(s) (coefficient alpha > or = 0.70); and (6) item-total correlations between 0.20 and 0.79. In addition, solutions were examined with respect to psychological theory and previous research. A 'general factor' (i.e. single latent dimension) solution which adhered to all a priori criteria was indicated. Twenty-four out of 25 items achieved salient loadings ranging from 0.46 to 0.80 on the general factor. The single item which failed to achieve salience, 'deviant grooming-skin picking', exhibited both substantial unique variance (0.997) and moderate reliability (r = 0.59, P<0.001). The internal consistency of the general factor was strong (alpha = 0.93) and all salient items were suitably correlated with the unit-weighted total score (r(item-total) = 0.41-0.77). The traditional CBC scoring system, which includes tallying the number of categories represented, would not be relevant in this PWS sample. In addition, the recommended tallying of the number of individual behaviours endorsed does not reflect the empirically indicated notion of compulsive behaviour in this special population. These findings indicate that the 24 salient items should be scored as a unit-weighted composite and that the score on the substantially unique item (skin picking) should be considered a separate measure when evaluating compulsive behaviours via the CBC in people with PWS. Intern Med. 1998 Dec. A 21 -year-old man with Prader-Willi syndrome (PWS) was hospitalized due to hyperglycemia. After diet therapy and transient insulin administration, his blood glucose levels improved. Based on the fact that his urinary C-peptide levels increased, the diabetes mellitus may have been due to insulin resistance with obesity. In addition, his testes had become atrophied. Testosterone levels remained low even after human chorionic gonadotropin (HCG) administration. Luteinizing hormone (LH) levels were also low after LH releasing hormone (LHRH) administration. The LH response increased slightly after daily LHRH administration, indicating hypothalamic hypogonadism. Follicle stimulating hormone (FSH) levels were, however, high and increased after LHRH administration. The selective FSH elevation may have been due to the accompanying idiopathic oligospermia. Genet Med. 1998 Nov-Dec. We report on 10 African Americans with Prader-Willi syndrome whose features differ from those of white patients with this condition. Growth is less affected, hand and foot lengths usually are normal, and the facies are atypical; this may lead to underdiagnosis in this population. We encourage clinicians to recognize these phenotypic differences so that diagnosis is not overlooked. Eur Child Adolesc Psychiatry. 1998 Sep. The platelet contents of monoamine oxidase (MAO-B) were analyzed in 17 children and young adults with Prader-Willi syndrome and 18 non-PWS comparison cases. MAO-B activity was significantly higher in the former group, suggesting monoamine dysfunction in Prader-Willi syndrome. [Note: MOA-B is an enzyme that catalyzes the inactivation or breakdown of monoamines such as the neurotransmitter dopamine and phenethylamines.] J Endocrinol Invest. 1998 Jul-Aug. Prader-Willi Syndrome (PWS) is a multisystem defect characterized by obesity, hypogenitalism and short stature for genetic background. Low GH serum levels have been found in patients with PWS and were related to a hypothalamic-pituitary dysfunction. We studied spontaneous nocturnal GH secretion and GH-response to provocative tests in five patients affected by PWS. We observed in three of them (Group A) abnormally low GH and IGF-1 serum levels. In the other two patients (Group B) GH secretion and IGF-1 serum levels were normal. In all patients no thyroid dysfunction was observed. These data might suggest the presence of two different subgroups of patients affected by PWS, from an endocrinological point of view. An abnormally low GH secretion would be evident only in a subgroup of patients, which appears to be normal in the remaining patients. This casistic is small in number, but if our data will be confirmed by more extensive studies it may be possible to identify a specific population of PWS patients who could benefit from recombinant GH-therapy. J Child Psychol Psychiatry. 1998 Jul. The personality profiles for youths with Prader-Willi, fragile-X, or Williams syndrome were compared to three matched groups attending regular schools. Using the California Child Q-Set (CCQ), both of the parents of the 39 children with Prader-Willi syndrome, 32 boys with fragile-X syndrome, 28 children with Williams syndrome, and children in the comparison groups provided independent personality descriptions in terms of the Big Five personality factors of Extraversion, Agreeableness, Conscientiousness, Emotional Stability, and Openness, along with Motor Activity and Irritability. Specific personality phenotypes for each of the three syndrome groups were found to be differentially related to parental behaviours (i.e. control and anger) and family contexts (i.e. experienced family stress, marital conflict, and parental consistency). Neuropediatrics. 1998 Jun. The Prader-Willi syndrome (PWS) is associated with a tendency to self-injury and a reduced sensitivity to painful stimuli. Somatosensory functions were studied in 5 children aged 11-13 years with PWS. Tactual perception in the hands (stereognosis) was apparently normal in 4 of them. Sensory nerve conduction velocities in the median nerve and latencies for sensory evoked potentials were similar in the PWS subjects and in 10 healthy controls indicating a preserved myelinisation of sensory nerve fibers in PWS. Sensory nerve action potential amplitudes in the PWS group were on an average only 40-50% of normal size (p = 0.03), suggesting a reduced number of normal axons in the median nerve. The results may be relevant for the impaired pain sensitivity in PWS because similar neurographic findings and a low density of peripheral nerve fibers have been reported in patients with hereditary or congenital insensitivity to pain. Eur Respir J. 1998 May. Hypercapnic respiratory failure is a common cause of death in the Prader-Willi syndrome. Its relationship to sleep-disordered breathing has not been established and there are no reports of its successful treatment. We have retrospectively reviewed the records of four patients with the syndrome, who developed ventilatory failure. Daytime arterial blood gas tensions and overnight oximetry traces before and during treatment were compared. Each patient had severe sleep-disordered breathing in association with daytime ventilatory failure. The median overnight mean arterial oxygen saturation (Sa,O2) was 82% and the median minimum was only 41.5%. Initial treatment was with nasal intermittent positive pressure ventilation, and in each case the daytime arterial blood gas tensions were normalized. The patients were maintained on nasal continuous positive airway pressure at night after discharge. Compliance has been good, and at last follow-up (after a median of 4.8 yrs) the daytime arterial gas tensions remained normal, while the median overnight mean arterial oxygen saturation was 95.5% and the median minimum was 84.5%. This study of patients with the Prader-Willi syndrome shows that daytime ventilatory failure is associated with sleep-disordered breathing. It can be reversed with nocturnal noninvasive ventilation and maintenance treatment with continuous positive airway pressure is well tolerated, with no deterioration in respiratory parameters. Ann N Y Acad Sci. 1998 Apr 15. Prader-Willi syndrome (PWS) is characterized by psychomotor and growth retardation, infantile hypotonia, characteristic facies, small hands and feet, dental abnormalities, and early onset of childhood hyperphagia with consequent obesity. PWS is associated with abnormalities of chromosome 15. Approximately 75% of patients have a deletion of 15q11q13 on the paternal homologue, whereas 20-25% have inherited both chromosome 15s from the mother and none from the father, a condition known as maternal uniparental disomy (UPD). Thus, it is a lack of paternal alleles in the 15q11q13 region that results in PWS. Thick, sticky saliva is a consistent finding in patients with PWS. We have characterized salivary flow and composition in individuals with PWS. Salivary flow in patients with PWS is approximately 20% of that in controls. In addition, the salivary ions and proteins are present in increased amounts, possibly reflecting a concentration effect relative to decreased water in the saliva. Both deletion and uniparental disomy patients exhibit these findings, suggesting that the gene(s) involved are subject to imprinting. J Pediatr Psychol. 1998 Apr. OBJECTIVE: Compare behavioral and emotional problems of children and adolescents with Prader-Willi Syndrome (PWS) and clients consulting mental health centers (MHC) and related behavioral and emotional problems to the children's personality in the PWS group. METHODS: Participants were 39 children with PWS and 585 matched MHC clients. Child Behavior Checklist (CBCL) syndromes were related to the Big-Five personality factors measured with the California Child Q-sort (CCQ). RESULTS: Mean CBCL Total Problems scores were not different for the PWS and MHC groups, but differences were found for several of the CBCL subscales. Patterns of correlations among CBCL scales were similar in both groups, although coefficients were generally higher in the PWS group, indicating higher comorbidity or co-absence of CBCL syndromes in children and adolescents with PWS. Personality profiles were specific for internalizing and Externalizing problems of children and adolescents with PWS. Clin Genet. 1998 Apr. An objective photoanthropometric method, useful for delineating craniofacial characteristics, was performed on 20 individuals with Prader-Willi syndrome (PWS; 14 males and 6 females) under 12 years of age and on growth hormone therapy (e.g. for 3-12 months) to determine the effects of therapy on craniofacial features in PWS. Facial parameters were measured from strict frontal and profile photographic 35 mm slides and compared with other facial measurements from the same face (e.g. palpebral fissure width to bizygomatic diameter). We studied 16 photoanthropometric craniofacial indices following previously established protocols. Our photoanthropometric data on 20 PWS subjects meeting diagnostic criteria further supported previous findings of a high midface, a broad interalar distance, a prominent high chin and broad ears in PWS patients without growth hormone therapy. In addition, while on growth hormone therapy, the high midface, broad interalar distance and prominent high chin appeared to accentuate over time in relationship to untreated PWS patients. Conversely, broad appearing ears were not accentuated by growth hormone therapy in the PWS subjects analyzed in this study. J Pediatr Endocrinol Metab. 1998 Mar-Apr. Diabetes mellitus has only rarely been reported in prepubertal children with Prader-Willi syndrome. All reported children have required insulin therapy. We report the development of a previously unrecognized association of non-insulin dependent diabetes mellitus in an obese 6 year-old child with Prader-Willi syndrome. She has never developed ketosis or acidosis, and she has been treated with oral hypoglycemic medication. J Clin Endocrinol Metab. 1998 Feb. 7B2 is a neuroendocrine chaperone interacting with the prohormone convertase PC2 in the regulated secretory pathway. Its gene is located near the Prader-Willi syndrome (PWS) region on chromosome 15. In a previous study we were able to show 7B2 immunoreactivity in the supraoptic nucleus (SON) or the paraventricular nucleus (PVN) in only three of five PWS patients. Here we report that in contrast with five other PWS patients, the neurons in the hypothalamic SON and PVN of the two 7B2-immunonegative PWS patients also failed to show any reaction using two antibodies directed against processed vasopressin (VP). On the other hand, even these two cases reacted normally with five antibodies that recognize different parts of the VP precursor. This finding pointed to a processing defect. Indeed, the same patients had no PC2 immunoreactivity in the SON or PVN, whereas PC1 immunoreactivity was only slightly diminished. In conclusion, in the VP neurons of two PWS patients, greatly reduced amounts of 7B2 and PC2 are present, resulting in diminished VP precursor processing. Am J Med Genet. 1998 Jan 6. Prader-Willi syndrome (PWS) is characterized by early childhood obesity, mental deficiency, hypogonadism, hypotonia, hypopigmentation, short stature, small hands and feet, and a characteristic face. It is the most common genetic cause of obesity and obesity is the most significant health problem for PWS patients. Ob protein (leptin), which is produced by adipose tissue, is thought to play a significant role in obesity; thus, unusually low plasma leptin levels, or relative loss of sensitivity to leptin in PWS subjects, could be an important factor in their obesity. We measured plasma leptin levels in 19 obese and 14 non-obese PWS patients [mean body mass index (BMI) 37.2 and 22.0, respectively] and compared these levels to those of 28 obese controls (mean BMI 35.5) and 16 non-obese control individuals (mean BMI 21.6). The mean plasma leptin concentration (ng/ml) for obese PWS subjects was 33.4 and 23.6 for non-obese PWS subjects. Obese control leptin was 36.2 ng/ml and non-obese control was 9.9. Among the control groups, leptin levels in females were significantly higher than those in males; the obese males and females had significantly higher leptin than their respective non-obese counterparts. These differences did not hold true for the PWS subjects. Leptin levels in obese PWS males and females were similar, and the same was true of the non-obese PWS males and females. The differences between obese and non-obese PWS subjects of both sexes were small and not significant. Comparing control groups with their PWS counterparts revealed no significant differences, with one exception: circulating plasma leptin levels in non-obese PWS males were nearly five times higher than in non-obese control males with similar BMI. This difference may reflect a more female pattern of fat distribution and hypogonadism, which are characteristic of PWS males. Leptin levels in PWS patients were not obviously correlated with the chromosome 15 finding seen in the patients. Pediatr Neurol. 1998 Jan.
Proton magnetic resonance spectroscopy of the brain in patients with Prader-Willi syndrome. Five patients with Prader-Willi syndrome underwent magnetic resonance imaging and proton magnetic resonance spectroscopy. Magnetic resonance images revealed mild abnormalities, including slight ventriculomegaly, cortical atrophy, and a small brainstem, in all cases. The N-acetylaspartate/Choline (NAA/Cho) and N-acetylaspartate/Creatine (NAA/Cr) ratios were decreased in one (Case 1) and two (Cases 1 and 4) patients, respectively. The Choline/Creatine (Cho/Cr) ratio did not differ from those in control subjects. Thus, in patients with Prader-Willi syndrome, it is thought that there may be neuron loss or a neuron dysfunction caused by a chromosome abnormality. Statistically significant relationships were observed between IQ (DQ) and the NAA/Cho and Cho/Cr ratios: r = 0.895 (P < .05, NAA/Cho ratio) and r = -0.898 (P < .05, Cho/Cr ratio). This suggests that the parietal lobe pathology detected on 1H-magnetic resonance spectroscopy may be associated with more global brain damage and with loss of cognitive functions. Hinyokika Kiyo. 1998 Jan. Little information is available regarding the correlation between Prader-Willi syndrome and urolithiasis. We report a patient with Prader-Willi syndrome with a renal uric acid (UA) stone. A 23-year-old male patient was admitted to our department with gross hematuria and left flank pain. The blood and urine examination demonstrated hyperuricemia with the presence of UA crystals in the urine. Excretory urography revealed a radiolucent stone (17 x 27 mm) in the left renal pelvis suggesting a UA stone. The stone was removed successfully using extracorporeal shockwave lithotripsy (ESWL) combined with medication for UA metabolism. The stone was thought to have formed as a result of overeating associated with Prader-Willi syndrome, and accompanying overproduction of purine. Genet Couns. 1998. No abstract available. Paediatr Anaesth. 1998. A review of a case series of sixteen anaesthetics in eight cases was undertaken to determine whether children with Prader-Willi syndrome present particular problems to the anaesthetist. Children in an early stage of the condition who are below their centile for weight present no specific problems. Children who are heavier than 97th centile weight have problems associated with their obesity: difficult intravenous access and sleep apnoea. Scoliosis was noted in both groups and was not associated with problems after minor surgery. Horm Res. 1998. Growth failure is a recognized feature of the Prader-Willi syndrome (PWS). Despite evidence that hypothalamic dysfunction accompanies the syndrome, the etiology of this growth failure remains controversial because most patients with PWS are obese. In order to contribute to resolution of this controversy, we performed a retrospective analysis of 16 obese and non-obese PWS children. GH deficiency was diagnosed in 12 of the 16 subjects and occurred independently of weight status. All of the non-obese subjects were GH deficient. Of the 4 GH-sufficient children, 2 were moderately obese and 2 were morbidly obese. One of these children had clinical evidence of GH deficiency including a low IGF-1 level. Only one of the children had evidence of GH deficiency and a normal IGF-1 level, a pattern that could be attributable to obesity. We conclude that most short children with PWS have growth hormone deficiency and that this deficiency probably results from hypothalamic dysfunction. [ 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 | 1999 | 1998 | 1997 | 1996 | 1995 | 1994 | 1993 | 1992 | 1991 | 1990 | 1980-1989 | 1979 and prior ] |