PubMed HealthSearch

Biomedical subjects

L Burd

Publications and source records attributed to L Burd.

At least 19 recordsLinked to original sources

Comorbid Tourette's disorder and bipolar disorder: an etiologic perspective.

OBJECTIVE: Using an epidemiologic approach, the authors attempt to elucidate relationships between Tourette's disorder and bipolar disorder. METHOD: Of 205 patients with Tourette's disorder in the North Dakota Longitudinal Tourette Syndrome Surveillance Project, 15 had comorbid bipolar disorder. A subset of the patients with Tourette's disorder had been included in earlier population-based prevalence studies of Tourette's disorder in children, adolescents, and adults. Minimal risk ratios were calculated for the patients with Tourette's disorder plus bipolar disorder by age group (children/adolescents and adults). This information was used to estimate genetic risk indicators for comorbid Tourette's disorder and bipolar disorder. RESULTS: The estimated risk of developing bipolar disorder among the study group of children, adolescents, and adults with Tourette's disorder was more than four times higher than the level expected by chance, but this finding did not reach statistical significance. It was indicative of trends, however. CONCLUSIONS: Comorbidity between Tourette's disorder and bipolar disorder does not appear to be due to chance co-occurrence of the two disorders. Although a genetic mechanism may play a causal role, in the absence of family studies an explanatory model involving the concept of canalization of basal-ganglia-mediated dysfunctions is offered. In such a construct, Tourette's disorder would be a likely accompaniment to other conditions, including bipolar disorder, whose pathogenic determinants might channel through neural pathways involving the basal ganglia. The presence of significant developmental disabilities may further enhance factors culminating in comorbid Tourette's disorder and bipolar disorder.

Adolescent

Desmopressin acetate and nocturnal enuresis: how much do we know?

OBJECTIVES: Desmopressin acetate (DDAVP) is promoted to treat nocturnal enuresis but indications for its use are unclear. We reviewed all randomized controlled trials to determine (1) short- and long-term efficacy, (2) responders, (3) dose-response curve, (4) side effects, and (5) comparative efficacy with other treatments. METHODS: A Medline search of the English language literature from January 1966 to August 1992, supplemented by contact with the drug companies, yielded 18 articles which were true randomized controlled trials (11 cross-over and 7 parallel studies). RESULTS: The 18 randomized controlled trials included 689 subjects for most of whom some other type of treatment had failed. All studies found decreased mean frequency of wetting ranging from 10% to 91%, but only 24.5% of subjects achieved short-term dryness. One study of DDAVP responders directly tested long-term dryness and 21% stayed dry. In three studies that incidentally reported on long-term effects 5.7% stayed dry after stopping DDAVP: There was wide variation in the type of patient included. Seven studies addressed prognostic factors. Children more than 9 years old and with fewer initial wet nights do better. Four studies seem to include almost exclusively monosymptomatic children with nocturnal enuresis (ie, primary nocturnal enuresis, positive family history, and no urinary symptoms). Results were no better than those which included mixed symptoms. Five studies attempted to address the dose-response issue. Despite some methodological issues, there is probably some dose-response effect. Side effects were infrequent in the 589 subjects who received DDAVP as opposed to placebo. No cases of water intoxication and no significant shifts in electrolytes were reported in the four studies which measured them. Nasal stuffiness, headache, epistaxis, and mild abdominal pain seem to be the only side effects noted, and these were uncommon. Only one study compared DDAVP with conditioning alarms. Alarm patients had 10% fewer wet nights and a better long-term result. CONCLUSIONS: DDAVP reduces wet nights in children for whom other treatments have failed but it produces complete dryness in a minority, and this is often a temporary effect. The literature focuses on short-term efficacy. The true role of DDAVP will be known when samples are carefully selected, prognostic factors are examined, and more comparisons with other treatments are conducted focusing on long-term outcomes. On the basis of current knowledge, DDAVP is inferior to conditioning alarms as a primary therapy.

Child

A preliminary study of the relationship between central auditory processing disorder and attention deficit disorder.

Fifteen boys aged six to ten who met the criteria for attention deficit disorder (ADD) were compared with ten boys who did not have ADD in a double-blind, placebo-controlled, single-crossover study of methylphenidate. To assess the degree of overlap between ADD and central auditory processing disorder (CAPD), all subjects were assessed on parent and teacher behavior rating scales, as well as a battery of CAPD tests at baseline and after three and six weeks of treatment. Twelve of the 15 subjects with ADD and none of the subjects without ADD met the criteria for CAPD. The subjects with ADD also responded to stimulant treatment on the measures of both ADD and CAPD. The overlap in the symptomatology of these disorders, the finding that the criteria for both disorders were met in 12 of 15 cases and the sensitivity of both ADD and CAPD measures to treatment with methylphenidate suggest that ADD and CAPD are closely related disorders. The implications of these results are three-fold. First, sustained attention is a critical feature of performance on CAPD tests and the current diagnostic criteria for CAPD make a clinical separation of the two disorders problematic. Second, stimulants appear to be a useful treatment for the symptoms of both ADD and CAPD. Third, CAPD tests may be a useful measure of ADD symptomatology and response to stimulants.

Analysis of Variance

Tourette syndrome and learning disabilities.

We reviewed the records of 42 consecutive cases of children with Tourette Syndrome (TS) who had IQs above 70, and contrasted the reading, reading comprehension, math, and spelling quotients with IQ scores to determine how many would meet criteria for a learning disability. The mean IQ of the 35 males and 7 females was 94.4 and was higher than the mean math score (82.8), spelling score (90.4), reading score (87.4), and reading comprehension score (85.3). Using a 1.5 standard deviation discrepancy, 51% met criteria for learning disability in at least one academic area; 21% had a 2-standard-deviation discrepancy. Children with TS frequently have learning disabilities, and assessment of academic achievement should be a routine aspect in the evaluation of such children.

Achievement

Prevalence of type I spinal muscular atrophy in North Dakota.

In order to establish the incidence and prevalence of type I spinal muscular atrophy (SMA Werdnig-Hoffmann disease) in North Dakota, we reviewed the death certificates for the past 8 years. Between 1980 and 1987 the prevalence of was 1.5 per 10,000. The incidence was 1 in 6,720. This suggests a carrier frequency of 1 in 41 in North Dakota with a gene frequency of 0.0122. In North Dakota, type I spinal muscular atrophy appears to be 3 to 10 times more common than in other locations.

Death Certificates

Huntington disease and childhood-onset Tourette syndrome.

A 40-year-old man with childhood-onset Tourette syndrome (TS) developed Huntington disease (HD). We believe this to be the first reported case of childhood-onset TS with adult onset HD. Discovery of other cases with both disorders may provide clues to the pathophysiology of both conditions.

Adult

Prevalence study of Rett syndrome in North Dakota children.

Service providers for children in the state of North Dakota were surveyed to determine the prevalence rate of Rett syndrome (RS). Five patients with definite RS were identified in a population of 203,801 children (98,932 girls) 0-18 years of age yielding a prevalence rate of RS of 1 in 40,760 in North Dakota children. For girls the rate of RS is 1 in 19,786. Similar surveys of other states using comparable modes of ascertainment will be important as points of comparison for prevalence rates of RS.

Adolescent

Management of sickle cell anemia and pregnancy.

There has been significant decrease in maternal morbidity and mortality of sickle cell disease patients during pregnancy due to better understanding of the pathophysiology of the disease and physiologic changes during pregnancy. Prophylactic blood transfusion does not appear to reduce complications in patients with sickle cell anemia. Patients with sickle hemoglobin C disease and with S beta thalassemia+ have fewer complications but still need close monitoring. Blood transfusion therapy should be made available for medical and obstetrical complications to include increasing hypoxemia, progressive anemia, acute chest syndrome, twin pregnancy, splenic sequestration syndrome, preeclampsia, septicemia, or prior to general anesthesia and surgery. Blood transfusion therapy is associated with hepatitis, allergic reaction, alloimmunization, AIDS, and iron overload states. These aspects should be considered prior to using blood transfusion therapy. Excellent prenatal monitoring and aggressive intervention should be instituted when problems arise for the successful management of the pregnant patient with sickle cell disease. Prenatal diagnosis and cord blood screening should be made available for the infant. Appropriate pediatric referral and prophylactic penicillin is recommended for the infant with sickle cell disease.

Adult

Educational achievement in non-verbal children: are they learning disabled?

From a data-base of all nonspeaking children in North Dakota we analyzed the data on those children functioning above the retarded range to determine the prevalence of children meeting the main inclusion criteria for learning disabilities (LD), a severe discrepancy between IQ and achievement. The mean IQ for this group of 38 nonspeaking, nonretarded children of 104.0 was significantly higher than IQ equivalent scores in the academic subjects of reading (66.4), math (70.4), written language (65.2), and spelling (71.2). Using a stringent criterion for an IQ-achievement discrepancy of 2 standard deviations, 27 of 38 (71%) met this criterion in at least one subject. Academic subjects dependent upon higher linguistic functioning, written language and reading, were more affected than spelling and math. While the vast majority (73%) of these 38 children were deaf, the prevalence of IQ-achievement discrepancies was also found in 57% of the nonspeaking children without hearing impairments. These data suggest the common practice of excluding a diagnosis of a learning disability in a deaf child on the basis of the child's hearing impairment may not be appropriate. Further research is needed on the role of speech in academic achievement.

Achievement

Management of pregnancy in sickle cell syndromes.

We have seen a marked decrease in maternal and perinatal morbidity and mortality among pregnant patients with sickle cell disease. This has been the result of coordinated efforts with the obstetric and hematologic teams. Patients are counseled prior to pregnancy regarding the risks and are given the opportunity to modify their life style to prepare for the additional metabolic burden of gestation. Once pregnant, they are instructed in the techniques to recognize and avoid complications. They are observed frequently for the appearance of pain crisis and other medical and obstetric complications. If complications are identified, they should be treated aggressively. Transfusion therapy is important in the management of patients; however, prophylactic transfusion does not change outcome. Although significant laboratory techniques aid in fetal and maternal supervision, the universal fundamentals of good clinical perinatal care provided through the combined efforts of the obstetrician and hematologist contribute to the framework for the modern management and successful outcome of patients with sickle cell disease during pregnancy.

Anemia, Sickle Cell

Prevalence of psychoactive drug use among North Dakota group home residents.

To determine the prevalence of psychoactive medication usage among persons with mental retardation residing in community settings in the state of North Dakota, we sent a questionnaire to all group homes serving persons with developmental disabilities. The return rate was 97%. Psychoactive medications were used by 37% of residents represented. Results were discussed in relation to previous studies that have primarily involved institutionalized populations.

Adolescent

Rett syndrome symptomatology of institutionalized adults with mental retardation: comparison of males and females.

Institutionalized adults with mental retardation (N = 297) were surveyed to determine the prevalence of symptoms of Rett syndrome. No symptom of the syndrome occurred more frequently in males than females. When symptoms were analyzed in clusters (e.g., severe mental retardation, no prenatal complications, walked before 15 months, and wide-based gait), no single cluster of symptoms appeared to differentiate males from females. However, as individuals, only females were found to meet the necessary criteria for a diagnosis of Rett syndrome. Symptoms were seen with equal frequency in this population and no one or two symptoms differentiated patients with and without Rett syndrome.

Adolescent

A prevalence study of Rett syndrome in an institutionalized population.

An institution for the mentally retarded was surveyed to determine the prevalence rate of Rett syndrome (RS). Four patients with definite RS and one with probable RS were identified in a population of 350, yielding a prevalence rate of 1 in 87, about 1% of institutionalized male and female patients with mental retardation. In this population of patients with severe and profound mental retardation (N = 297), 138 females were surveyed, suggesting a prevalence rate among females of 1 in 34 in an institutional population of persons with mental retardation. Surveys of institutions for persons with mental retardation may be an effective method to identify adults with RS.

Adolescent