New Approaches to the Genetic Analysis of Neuroticism and Anxiety

The completion of the human genome project and the complementary genome projects for other species has broadened the scope for novel bioinformatic approaches to quantitative trait locus (QTL) identification. A key issue for quantitative trait nucleotide (QTN) identification is progressing from a large QTL peak, spanning perhaps 50 cM and many hundreds of genes, to a gene or nucleotide variant which is responsible for that QTL effect. The complementary use of mouse models to dissect large syntenic loci in humans is a powerful method for reducing QTL intervals to the order of 1 Mb. This paper presents an overview of the approaches used in our laboratory to ultra-fine map QTLs for anxiety-related traits, and to identify quantitative trait genes (QTG). As new genetic techniques and statistical approaches arise, we are getting closer to identifying those long sought after QTNs.     

Are myopic children more anxious than their non-myopic peers?

Two hundred and fifty two children aged between nine and thirteen years of age were classified according to their refractive error, based on static retinos-copy. Anxiety was determined using the Eysenck Personality Questionnaire Junior (EPQ), and a subjective rating given by each child's teacher. Multiple regression analysis revealed no significant relationship between refractive error and anxiety for the whole population. A significant relationship was found for the female subpopulation where there was a trend for hyperopes to manifest more anxiety, but this effect was produced by a single extreme subject. A comparison of the 25 myopes in the sample and 25 randomly selected control children revealed no differences between the groups on personality variables related to anxiety.     

Migraine,major depression,panic disorder,and personality traits in women aged 40-74 years: a population-based study

This study investigates the associations between migraine on the one hand and lifetime major depression, lifetime panic disorder, and neuroticism evaluated using the Swedish universities Scales of Personality on the other. A neurologist clinically assessed 728 women aged 40-74 years attending a population-based mammography screening programme. The associations between lifetime migraine and personality traits and psychiatric disorders were insignificant in multivariable analysis. However, in old women (60-74 years) the risk for active migraine was strongly associated with a history of major depression and high levels of stress susceptibility and somatic trait anxiety. Furthermore, in old women, high levels of stress susceptibility and somatic trait anxiety were associated with low ratings of migraine pain intensity and lower levels of these traits with high ratings after controlling for disability during migraines, whereas there were only small differences in middle-aged women. The results suggest that certain aspects of neuroticism are important mental correlates of the ability of old women to endure migraine pain.     

A prospective study of life satisfaction, neuroticism and breast cancer risk (Finland)

Objective: To prospectively investigate whether life satisfaction and neuroticism, two measures reflecting aspects of anxiety/depression, are related to risk of breast cancer. Methods: The study population comprised 12,032 women from the population-based Finnish Twin Cohort. Life satisfaction and neuroticism were assessed in health questionnaires in 1975 and 1981. During 21 years of follow-up, 238 cases of breast cancer were documented in the study cohort through record linkage to the Finnish Cancer Registry. Results: After adjustment for age and other important covariates, the hazard ratios were 1.0 (reference), 0.9 (95% confidence interval 0.6–1.3) and 1.0 (0.7–1.6) by decreasing level of life satisfaction (satisfied, intermediate, dissatisfied), and 1.0 (reference), 1.0 (0.7–1.4) and 0.8 (0.6–1.2) by increasing level of neuroticism (low, intermediate, high). These results did not change after accounting for possible changes in the levels of life satisfaction and neuroticism between 1975 and 1981. The null results were also confirmed with the use of a nested case–control study within twin pairs that became discordant for breast cancer during the follow-up. Conclusions: Our data indicate that life satisfaction and neuroticism are not substantially associated with breast cancer risk. These findings provide epidemiological evidence against the doubts that breast cancer would be more likely to occur in unhappy, dissatisfied, and worrying women.     

Clinical characteristics of familial and non-familial bipolar disorder

Objective: To explore the clinical characteristics of familial and non-familial bipolar disorder.

Method: Twenty subjects with bipolar disorder, who also had a family history of bipolar disorder in a first degree relative, were matched for current age, age of first onset of bipolar disorder and gender with 20 subjects with bipolar disorder who had no family history of any psychiatric disorders in first or second degree relatives.

Results: Fourteen subjects in each group were female. The mean age at interview was 45.2 years and the mean age at first admission was 26 years. Although familial and non-familial probands had an equivalent number of illness episodes, familial probands were significantly more likely to experience mixed states as compared to non-familial probands. The latter experienced significantly more depressive episodes and had significantly higher neuroticism (N) scores on the Eysenck Personality Inventory (EPI; Eysenck H, Eysenck S. Manual of the Eysenck Personality Inventory. London: University of London Press, 1964.).

Conclusions: If the results are replicated, they have important implications. For example, such data may aid decisions about the targeting of additional psychosocial interventions in high N score cases. Researchers will wish to investigate whether mixed states show a stronger association with early age of onset or family history of BD.     

Locus of control in chronic anxiety disorders

The relationship between psychopathology and the personality trait, locus of control, was examined in 116 adult outpatients diagnosed as having chronic anxiety disorder. Measures consisted of state and trait scales, a measure of social adjustment, and a measure of disturbance during childhood. Patients with an external locus of control were more depressed, had higher levels of state anxiety, and exhibited more indecisiveness, fatigue and agoraphobia than those with an internal locus of control. Externally oriented patients also scored higher on neuroticism and trait anxiety and scored lower on social adjustment. On the somatic scales, externally oriented patients rated themselves, in contrast to physician's rating, as being more symptomatic than internal patients, suggesting the presence of a help-seeking attitude. Locus of control may be of importance in the formulation of therapy and prognosis in patients with anxiety disorders.     

Gender and personality in alcoholism

The topic gender and personality in alcoholism is discussed on the background of a research project on clinical aspects of alcoholism at the University of Würzburg, Germany. The data of this study are presented in the context of two questions: Which personality differences are there between women and men dependent on alcohol, and is there a connection between these personality differences and features of the alcohol dependence? Additionally, we take a look at gender-related differences in the development of alcoholism. In a first step, gender differences in the development and the course of alcoholism are investigated. The data revealed only weak differences between female and male alcoholics when important confounding variables like age and education are taken into consideration. Secondly, the female and male alcoholics are matched according to age and education and their personality structures are compared by using several well-established and standardized self-report questionnaires. No serious gender differences concerning the main characteristics of alcohol dependence could be discovered. However, some remarkable personality differences between female and male alcoholics are found: women scored significantly higher on Neuroticism and Harm-Avoidance while men reached significantly higher scores on Venturesomeness and Sensation-Seeking. In order to detect a possible connection between alcoholism and gender-related personality differences, both males and females are subdivided into two groups using the scores of Neuroticism, Harm-Avoidance, Venturesomeness and Sensation-Seeking, respectively. We have found no indication for a gender-specific relevance of personality differences between female and male alcoholics with regard to Harm-Avoidance, Venturesomeness or Sensation-Seeking. However, differences in Neuroticism have revealed a greater relevance in alcohol-dependent women than in men.