Psychological risk factors of incidence of breast cancer: a prospective cohort study in Finland.
BACKGROUND
Belief that depression and other psychological factors predict breast cancer is common, but there have been few prospective epidemiological studies on this relationship.


METHODS
The relationship between depression, personality traits, illness attitudes, life events and health history, and breast cancer risk was studied in a prospective, 6-9 year follow-up of a cohort study of 10892 Finnish women of 48-50 years of age at the baseline. Cancer cases were obtained from the Cancer Registry of Finland. Multivariate logistic regression analysis was performed controlling for socioeconomic factors, family history of cancer, parity, and health behaviours.


RESULTS
Breast cancer incidence in the cohort was 1.15 times the average in age group 50-59. There was no evidence of depression, trait anxiety, cynical distrust, or coping being significant predictors of breast cancer incidence.


CONCLUSIONS
In this cohort study with the 6-9 year follow-up, psychological factors such as depression, trait anxiety, cynical distrust, or coping did not increase breast cancer risk.
Aro
A R
AR
Department of Epidemiology and Health Promotion, National Public Health Institute, Helsinki, Finland. arja.aro@ktl.fi
De Koning
H J
HJ
Schreck
M
M
Henriksson
M
M
Anttila
A
A
Pukkala
E
E
D000223:Adaptation, Psychological; D001008:Anxiety Disorders / Q000175:diagnosis / Q000453:epidemiology*; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000523:psychology*; D015331:Cohort Studies; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D012042:Registries; D012307:Risk Factors; D011795:Surveys and Questionnaires