Personality predicts quality of life six months after the diagnosis and treatment of breast disease.

Background: Quality of Life (QoL) is an important outcome measure in oncology. QoL is influenced by personality traits, such as anxiety. To assess the influence of personality on QoL in women with breast cancer, a longitudinal prospective cohort study was done.
Methods: Ninety-one patients with breast cancer and 111 patients with benign diagnoses completed prior to the diagnosis and 1, 3, and 6 months after diagnosis and treatment a set of questionnaires.
Results: Overall QoL showed no significant differences between the two groups. The influence of trait anxiety was considerable for all measurement moments. Trait anxiety is accountable for up to 40.6% of the variance in QoL scores. Forty-five women in the benign group scored high on trait anxiety, and 40 women in the breast cancer group. Women with a high trait anxiety score were 3 times as likely to have a low general QoL six months after diagnosis and possible surgery, irrespective of the diagnosis (breast cancer or benign problems). When the women were divided into four groups based on the diagnosis and the score on trait anxiety, there was a significant difference in scores on general QoL between the groups on all measurement moments, with a significant lower score for the two groups with a high score on trait anxiety (P < 0.001).
Conclusion: Trait anxiety rather than the diagnosis breast cancer determined whether patients experienced a low QoL.