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A E Pulver

Publications and source records attributed to A E Pulver.

At least 37 records · Page 2Linked to original sources
PubMed1995

Schizophrenia: a genome scan targets chromosomes 3p and 8p as potential sites of susceptibility genes.

Using a systematically ascertained sample of 57 families, each having 2 or more members with a consensus diagnosis of schizophrenia (DSM-III-R criteria), we have carried out linkage studies of 520 loci, covering approximately 70% of the genome for susceptibility loci for schizophrenia. A two-stage strategy based on lod score thresholds from simulation studies of our sample identified regions for further exploration. In each region, a dense map of highly informative dinucleotide repeat polymorphisms (heterozygosity greater than .70) was analyzed using dominant, recessive, and "affected only" models and nonparametric sib pair identity-by-descent methods. For one region, 8p22-p21, affected sib-pair analyses gave a P value = .0001, corresponding to a lod score approximately equal to 3.00. For 8p22-p21, the maximum two-point lod score occurred using the "affected only" recessive model (ZMAX = 2.35; theta M = theta F); allowing for a constant sex difference in recombination fractions found in reference pedigrees, ZMAX = 2.78 (theta M/theta F = 3). For a second region, 3p26-p24, the maximum two-point lod score was 2.34 ("affected only" dominant model), and the affected sib-pair P value was .01. These two regions are worthy of further exploration as potential sites of susceptibility genes for schizophrenia.

Biomarkers↗
PubMed1995

Differences in social class among psychotic patients at inpatient admission.

A cross-sectional assessment of differences in social class and other sociodemographic variables at hospital admission for patients with psychotic disorders was carried out through a systematic survey of psychotic patients admitted to greater Baltimore psychiatric facilities between 1983 and 1989. Female patients, first-admission patients, and patients with bipolar disorder or other, nonschizophrenic psychosis were more likely to have been admitted to community, university, and private hospitals than to state hospitals. Patients in medium and higher social class categories were 1.29 to 2.57 times more likely to be admitted to community, university, and private hospitals than to state hospitals.

Adolescent↗
PubMed1994

Sequential strategy to identify a susceptibility gene for schizophrenia: report of potential linkage on chromosome 22q12-q13.1: Part 1.

To identify genes responsible for the susceptibility for schizophrenia, and to test the hypothesis that schizophrenia is etiologically heterogeneous, we have studied 39 multiplex families from a systematic sample of schizophrenic patients. Using a complex autosomal dominant model, which considers only those with a diagnosis of schizophrenia or schizoaffective disorder as affected, a random search of the genome for detection of linkage was undertaken. Pairwise linkage analyses suggest a potential linkage (LRH = 34.7 or maximum lod score = 1.54) for one region (22q12-q13.1). Reanalyses, varying parameters in the dominant model, maximized the LRH at 660.7 (maximum lod score 2.82). This finding is of sufficient interest to warrant further investigation through collaborative studies.

Adult↗
PubMed1994

Follow-up of a report of a potential linkage for schizophrenia on chromosome 22q12-q13.1: Part 2.

A collaboration involving four groups of investigators (Johns Hopkins University/Massachusetts Institute of Technology; Medical College of Virginia/The Health Research Board, Dublin; Institute of Psychiatry, London/University of Wales, Cardiff; Centre National de la Recherche Scientifique, Paris) was organized to confirm results suggestive of a schizophrenia susceptibility locus on chromosome 22 identified by the JHU/MIT group after a random search of the genome. Diagnostic, laboratory, and analytical reliability exercises were conducted among the groups to ensure uniformity of procedures. Data from genotyping of 3 dinucleotide repeat polymorphisms (at the loci D22S268, IL2RB, D22S307) for a combined replication sample of 256 families, each having 2 or more affected individuals with DNA, were analysed using a complex autosomal dominant model. This study provided no evidence for linkage or heterogeneity for the region 22q12-q13 under this model. We conclude that if this region confers susceptibility to schizophrenia, it must be in only a small proportion of families. Collaborative efforts to obtain large samples must continue to play an important role in the genetic search for clues to complex psychiatric disorders such as schizophrenia.

Adult↗
PubMed1994

Extended latent class approach to the study of familial/sporadic forms of a disease: its application to the study of the heterogeneity of schizophrenia.

When no method exists for detecting genetic forms of a disorder, epidemiologists classify probands according to the presence or absence of an affected relative (familial or sporadic). Not only is this a surrogate measure but if the risk for the disorder is associated with characteristics such as age and gender, then probands with varied distributions of these characteristics among their relatives are subject to misclassification. A latent class approach is presented which explicitly models the relationship between the affected status of the relatives and the unobservable familial/sporadic status of the proband in order to adjust for these characteristics. Lastly, an approach is introduced to correct for attenuation in measures of association between familial/sporadic status and other variables that could result if probands are misclassified. This approach incorporates the latent class probabilities directly into the regression model without classifying probands. These methods are applied to a study of the heterogeneity of schizophrenia.

Adolescent↗
PubMed1994

Psychotic inpatients' social class and their first admission to state or private psychiatric Baltimore hospitals.

Social class differences were investigated among patients admitted to public and private psychiatric hospitals. Participants included first admission White psychotic men admitted to Baltimore metropolitan area hospitals between 1983 and 1989. After adjusting for age and diagnosis, patients with low levels of skills/credentials were found to be more likely than patients with higher levels to be admitted to state psychiatric hospitals. These findings underscore the persistence of social class as a determinant of differences in the use of psychiatric care.

Adolescent↗
PubMed1993

Work environment and schizophrenia: an extension of the arousal hypothesis to occupational self-selection.

The present study investigated a possible mechanism underlying the occupational self-selection of future schizophrenic patients prior to their first admission. More precisely, we explored whether schizophrenic patients are more likely than other psychotic patients to work in environments with a low potential for arousal (low complexity environments) in the last full-time job that preceded their hospitalization. All first admissions with psychotic symptoms to 15 hospitals providing inpatient psychiatric services in the Baltimore-Washington area were surveyed during a 6-year period. Patients diagnosed with schizophrenia were compared to patients diagnosed with bipolar disorder and other psychotic disorders to evaluate the suspected association. Study participants were assessed with a modified version of the Diagnostic Interview Schedule. Standard survey questions were used to assess occupational background. A measure based on the dictionary of occupational titles (DOT) was used to estimate the degree of complexity to which patients had been exposed in their last full-time occupation. Data were analyzed using multinomial logistic regression. After adjustment for age, gender, marital status, unemployment, socioeconomic status, hospital type, and physical demands and hazards on the job, patients with schizophrenia were more likely to have been working in low complexity environments in their last full-time jobs (e.g., janitors, gardeners, guards) than patients with bipolar disorder or with other psychotic disorders. Alternative explanations and potential implications regarding which work environments might be best suited to the social behavior of patients with schizophrenia are examined.

Adolescent↗
PubMed1992

Schizophrenia: gender and familial risk.

The morbid risks for schizophrenia and any nonaffective psychosis in the first degree relatives of male and female schizophrenic probands were compared utilizing Cox proportional hazards models. The schizophrenic probands (275 male; 106 female) were drawn from a larger sample of hospitalized patients obtained by systematically screening all psychiatric admissions to 15 facilities over a six-year period. Proband diagnoses (DSM-III) were based on a direct assessment of the patient and a review of medical records. The family history method was used to obtain information about the first degree relatives of the probands. Cox proportional hazards models were adjusted for duration of illness of the proband and gender of the relatives. First degree relatives of female probands had significantly higher morbid risks for schizophrenia and nonaffective psychosis than relatives of male probands. The differential risk for schizophrenia in the relatives of male and female probands demonstrated in this study, as well as others, suggests that males and females may be at different risk for subtypes of the disorder.

Adult↗
PubMed1992

Risk factors in schizophrenia. Season of birth, gender, and familial risk.

The risk for schizophrenia among first-degree relatives of schizophrenic probands obtained from an epidemiological sample using family history methods was examined to determine whether month of birth of the proband was associated with familial risk. The results of this study of the first-degree relatives of 106 female schizophrenics and 275 male schizophrenics suggested that the relatives of probands born in the months February to May had the highest risk, although the association between month of birth and familial risk among the male probands was present only for those relatives who had onset of schizophrenia before the age of 30.

Adult↗
PubMed1992

Season of birth of siblings of schizophrenic patients.

The hypothesis that mothers of winter-spring-born schizophrenics have an unusual pattern of conception which results in an excess of winter-spring births was tested by studying the distribution of birth-dates of 401 siblings of 120 winter-spring-born schizophrenics and 157 siblings of 59 winter-spring-born controls. All analyses were gender-specific. The results suggest there is no association between the probability of a winter-spring date of birth and being a sibling of a winter-spring-born schizophrenic or control.

Adult↗
PubMed1991

Estimating effects of proband characteristics on familial risk: II. The association between age at onset and familial risk in the Maryland schizophrenia sample.

In this report we apply methods outlined in the companion paper [Liang, Genet Epidemiol 8:329-338, 1991] to study the association between proband age at onset and familial risk among first-degree relatives of 374 schizophrenic probands. The analyses take into consideration the potential problems of censoring and correlation of age at onset within families. All analyses were done by gender of the proband; age at onset was dichotomized. The results of the analyses of the male probands suggest that there is an increased risk of schizophrenia among the relatives of male probands who have an onset prior to age 17 when compared to relatives of male probands who have an onset later than 16. We did not find an association between age at onset and familial risk among the female probands, but this may be due to the smaller number of female probands and the lower power associated with the analyses.

Adolescent↗
PubMed1991

Psychiatric morbidity in the relatives of patients with DSM-III schizophreniform disorder: comparisons with the relatives of schizophrenic and bipolar disorder patients.

Risks for psychiatric disorders (RDC) among first degree relatives of DSM-III schizophreniform, bipolar, and schizophrenic probands obtained from an epidemiologic sample using family history methods were examined. The relatives of the schizophreniform probands differed from the relatives of the schizophrenic and bipolar probands. The relatives of schizophreniform probands had significantly higher rates of affective illnesses (with the exception of bipolar illness) than the relatives of schizophrenic probands, and they had a significantly higher rate of psychotic affective disorders than the relatives of the bipolar probands.

Adolescent↗
PubMed1990

Age-incidence artifacts do not account for the season-of-birth effect in schizophrenia.

Contrary to the position taken by Lewis (1989), several articles have demonstrated an association between season of birth and the risk of schizophrenia after controlling for the age-incidence effect. The method used by Pulver et al. (1983) was misinterpreted by Lewis. Clarification of this method is provided along with additional references related to the season-of-birth issue.

Adult↗
PubMed1990

Schizophrenia: age at onset, gender and familial risk.

In a family history study of 366 schizophrenic probands and their 1851 first-degree relatives, we found a relationship between age at onset of psychosis in the male probands and the risk for schizophrenia in their relatives. The relatives of male schizophrenic probands whose onset of psychosis occurred when they were younger than 17 years of age had an increased risk of schizophrenia when compared with the relatives of male probands with an age at onset greater than 17. We did not find an association between age at onset of psychosis in the female probands and familial risk. Cox proportional hazards models permitted us to examine the relationship between age at onset of psychosis in the probands and familial risk while controlling for possible confounding effects.

Adolescent↗