Henrik L Ewald

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BACKGROUND Although a family history of schizophrenia is the best-established risk factor for schizophrenia, environmental factors such as the place and season of birth may also be important. METHODS Using data from the Civil Registration System in Denmark, we established a population-based cohort of 1.75 million persons whose mothers were Danish women(More)
OBJECTIVE Individuals with schizophrenia and their relatives tend to have either higher or lower than expected prevalences of autoimmune disorders, especially rheumatoid arthritis, celiac disease, autoimmune thyroid diseases, and type 1 diabetes. The purpose of the study was to estimate the association of schizophrenia with these disorders as well as a(More)
The involvement of genetic factors in the etiology of autism has been clearly established. We undertook a genome-wide search for regions containing susceptibility genes for autism in 12 subjects with childhood autism and related pervasive developmental disorders (PDDs) and 44 controls from the relatively isolated population of the Faroe Islands. In total,(More)
BACKGROUND Few population-based studies have addressed risk factors for bipolar affective disorder. OBJECTIVE To study the possible association between bipolar affective disorder and history of mental illness in a parent or sibling; urbanicity of birth place; season of birth; sibship characteristics, including birth order; influenza epidemics during(More)
The aim of this study was to investigate the internal and external validity of the Whiteley Index as a screening instrument for somatization illness. A 14-item version of the Whiteley Index for hypochondriacal traits was given to 99 of 191 consecutive primary care patients, aged 18-65 years, and to 100 consecutive patients, aged 18-60 years, admitted for(More)
BACKGROUND Advanced paternal age has been suggested as a possible risk factor for schizophrenia. It is not known whether this is explained by known risk factors for schizophrenia, including sibship characteristics, death of a parent before first hospital admission, season and place of birth, and family history of psychiatric illness, or by socioeconomic(More)
Recent evidence from postmortem studies suggests that GAD1 encoding the gamma-aminobutyric acid (GABA) synthetic enzyme GAD67 is a functional candidate susceptibility gene for both bipolar affective disorder (BPAD) and schizophrenia. Previous studies suggest linkage between D2S326 near GAD1 and BPAD. We systematically screened GAD1 exons, flanking intronic(More)
Significant evidence for linkage between bipolar affective disorder and markers on chromosome 4p16 has been reported in Scottish families. Linkage analyses using 16 DNA markers covering more than 50 cM from chromosome 4pter-4p12, including candidate genes encoding the dopamine D5 receptor and an adrenergic receptor (2C), were performed in two Danish(More)
BACKGROUND Several case reports and reviews have suggested an increased incidence of schizophrenia or bipolar disorder among persons with sex chromosome aneuploidies, but this observation may have been caused by biased sampling. METHODS The 1122 individuals with sex chromosome aneuploidies registered in the Danish Cytogenetic Central Register were(More)
Chromosome 12q23-q24.1 has been implied by a few linkage and association studies as a candidate region for affective disorder. The present study investigated for linkage between bipolar affective disorder and 16 microsatellite markers covering chromosome 12q22-q24 in two Danish families. Assuming homogeneity and a dominant mode of inheritance, a significant(More)