Subclinical psychopathology and socio-economic status in unaffected twins discordant for affective disorder.
BACKGROUND
The most potent risk factor for affective disorders is a family history of affective disorder but the specific factors that are transmitted in families are unknown. It is possible to investigate the relation between risk factors and affective disorder by using a high-risk design e.g.: a study of the healthy relatives of patients with affective disorders.


OBJECTIVE
To compare psychopathology and socio-economic status between twins with a co-twin history of affective disorder and twins without.


METHODS
In a cross-sectional high-risk case-control study, healthy monozygotic and dizygotic twins with (High-Risk twins) and without (Low-Risk twins) a co-twin history of affective disorder were identified through nation-wide registers. Participants were assessed using semi-structured psychiatric interviews and self-rating of psychopathology.


RESULTS
High-Risk twins had a lower education level, a lower work position and tendency towards being more often unemployed and early retired than the Low-Risk twins. Furthermore, they presented higher rates of subclinical affective symptoms and were more likely to experience a minor psychiatric diagnosis.


CONCLUSIONS
Healthy twins with a high genetic liability to affective disorder seem to present lower socio-economic status, higher rates of subclinical affective symptoms and more often experience a minor psychiatric diagnosis than twins with no familial history of affective disorder. It is not possible from the present cross-sectional data to determine the causality of these findings, thus genetic liability to affective disorder, socio-economic status and minor psychopathology seem to have a complex interrelation.
Christensen
Maj Vinberg
MV
Department of Psychiatry, Rigshospitalet University Hospital of Copenhagen, Blegdamsvej 9, DK-2100 Copenhagen, Denmark. Maj.Vinberg@rh.dk
Kyvik
Kirsten Ohm
KO
Kessing
Lars Vedel
LV
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016009:Chi-Square Distribution; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004200:Diseases in Twins; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019964:Mood Disorders / Q000235:genetics / Q000503:physiopathology / Q000523:psychology; D011599:Psychopathology; D012042:Registries; D012307:Risk Factors; D012959:Socioeconomic Factors; D018433:Twin Studies as Topic