Specificity in familial aggregation of phobic disorders.
ABSTRACT To investigate whether each of three DSM-III-R phobic disorders (simple phobia, social phobia, and agoraphobia with panic attacks) is familial and "breeds true."
Rates of each phobic disorder were contrasted in first-degree relatives of four proband groups: simple phobia, social phobia, agoraphobia with panic attacks, and not ill controls. Phobia probands were patients who had one of the phobia diagnoses but no other lifetime anxiety comorbidity.
We found moderate (two- to fourfold increased risk) but specific familial aggregation of each of the three DSM-III-R phobic disorders.
These results support a specific familial contribution to each of the three phobia types. However, conclusions are limited to cases occurring without lifetime anxiety comorbidity and do not imply homogeneity within categories.
- SourceAvailable from: Rachel G Klein
- [Show abstract] [Hide abstract]
ABSTRACT: To explore the genetic and environmental factors underlying the co-occurrence of lifetime diagnoses of DSM-IV phobia. Female twins (n=1430) from the population-based Norwegian Institute of Public Health Twin Panel were assessed at personal interview for DSM-IV lifetime specific phobia, social phobia and agoraphobia. Comorbidity between the phobias were assessed by odds ratios (ORs) and polychoric correlations and multivariate twin models were fitted in Mx. Phenotypic correlations of lifetime phobia diagnoses ranged from 0.55 (agoraphobia and social phobia, OR 10.95) to 0.06 (animal phobia and social phobia, OR 1.21). In the best fitting twin model, which did not include shared environmental factors, heritability estimates for the phobias ranged from 0.43 to 0.63. Comorbidity between the phobias was accounted for by two common liability factors. The first loaded principally on animal phobia and did not influence the complex phobias (agoraphobia and social phobia). The second liability factor strongly influenced the complex phobias, but also loaded weak to moderate on all the other phobias. Blood phobia was mainly influenced by a specific genetic factor, which accounted for 51% of the total and 81% of the genetic variance. Phobias are highly co-morbid and heritable. Our results suggest that the co-morbidity between phobias is best explained by two distinct liability factors rather than a single factor, as has been assumed in most previous multivariate twin analyses. One of these factors was specific to the simple phobias, while the other was more general. Blood phobia was mainly influenced by disorder specific genetic factors.Psychological Medicine 09/2011; 41(9):1987-95. DOI:10.1017/S0033291710002436 · 5.43 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Clinical studies suggest a familial association between panic disorder and alcohol use disorders but this relationship has not been examined in a representative community sample. The objective of this study is to examine the familial association between panic disorder and alcohol use disorders among adults in the community. Data were drawn from the NESARC, a nationally representative sample of over 43,000 adults in the United States. Rates of alcohol use disorders were examined using the family history method in first-degree relatives (FDRs) of adults with panic disorder. Analyses were adjusted for demographics, alcohol use disorders in the proband, and anxiety disorders in the FDRs. First-degree relatives of adults with panic disorder have significantly higher odds of alcohol use disorders, compared with FDRs of adults without panic disorder. These associations persist after adjusting for demographic characteristics, alcohol use disorders in the proband, and anxiety disorders in the FDR's. Consistent with findings from clinical studies, this is the first population-based study to show a familial link between panic disorder and alcohol use disorders. This association appears independent of the influence of comorbidity of alcohol use disorders and anxiety disorders, suggesting a potential familial and/or genetic pathway. Future longitudinal studies will be needed to further understand the mechanism of this observed association.Journal of Psychiatric Research 02/2011; 45(8):1123-7. DOI:10.1016/j.jpsychires.2011.01.017 · 4.09 Impact Factor