Chemotherapy and Post-traumatic Stress in the Causation of Cognitive Dysfunction in Breast Cancer Patients.

Background: Cancer-related cognitive dysfunction has mostly been attributed to chemotherapy; this explanation, however, fails to account for cognitive dysfunction observed in chemotherapy-naïve patients. In a controlled, longitudinal, multisite study, we tested the hypothesis that cognitive function in breast cancer patients is affected by cancer-related post-traumatic stress. Methods: Newly diagnosed breast cancer patients and healthy control subjects, age 65 or younger, underwent three assessments within one year, including paper-and-pencil and computerized neuropsychological tests, clinical diagnostics of post-traumatic stress disorder (PTSD), and self-reported cognitive function. Analysis of variance was used to compare three groups of participants-patients who did or did not receive chemotherapy and healthy control subjects-on age- and education-corrected cognitive performance and cognitive change. Differences that were statistically significant after correction for false discovery rate were investigated with linear mixed-effects models and mediation models. All statistical tests were two-sided. Results: Of 226 participants (166 patients and 60 control subjects), 206 completed all assessment sessions (attrition: 8.8%). Patients demonstrated overall cognitive decline (group*time effect on composite z -score: -0.13, P = .04) and scored consistently worse on Go/Nogo errors. The latter effect was mediated by PTSD symptoms (mediation effect: B = 0.15, 95% confidence interval = 0.02 to 0.38). Only chemotherapy patients showed declined reaction time on a computerized alertness test. Overall cognitive performance correlated with self-reported cognitive problems at one year ( T = -0.11, P = .02). Conclusions: Largely irrespective of chemotherapy, breast cancer patients may encounter very subtle cognitive dysfunction, part of which is mediated by cancer-related post-traumatic stress. Further factors other than treatment side effects remain to be investigated.

Clinically assessed posttraumatic stress in patients with breast cancer during the first year after diagnosis in the prospective, longitudinal, controlled COGNICARES study.

OBJECTIVE: There is ongoing debate whether cancer qualifies as traumatic stressor. We investigated prevalence and course of posttraumatic stress in patients with early breast cancer (BC) during their first year after diagnosis and determined effects of mastectomy and chemotherapy. METHODS: Patients with stage 0-III BC aged ≤65 years were evaluated with the Structured Clinical Interview for DSM-IV modules for acute and posttraumatic stress disorder (ASD and PTSD, respectively) before treatment, after chemotherapy, and 1 year after diagnosis. Matched controls were assessed at matched intervals. Effects of time, mastectomy, and chemotherapy on BC-related PTSD symptom severity were tested with linear mixed model analysis. RESULTS: Stress disorder (ASD or PTSD) related to BC was diagnosed in 6 (3.6%) of 166 patients before treatment and in 3 patients (2.0%) 1 year later. The rate of patients who experienced PTSD symptoms related to BC decreased from 82.5 to 57.3% (p < 0.001), and the mean of BC-related PTSD symptoms diminished from 3.1 to 1.7 (p < 0.001). Only university education significantly predicted the course of BC-related PTSD symptom severity (p = 0.009). In 60 controls, no diagnosis of stress disorder, a rate of 18% women experiencing PTSD symptoms, and a mean of 0.4 PTSD symptoms (p vs. patients <0.001) were found. CONCLUSIONS: Most newly diagnosed patients with BC experience PTSD symptoms, whereas full diagnoses of DSM-IV stress disorder are rare. Symptoms diminish somewhat within 1 year furthered by university education but independently from mastectomy and chemotherapy. Throughout the year after diagnosis, having BC entails markedly increased PTSD symptom burden. Copyright © 2016 John Wiley & Sons, Ltd.

Elucidating pretreatment cognitive impairment in breast cancer patients: the impact of cancer-related post-traumatic stress.

BACKGROUND: Pretreatment cognitive impairment in cancer patients is well established but unexplained. Similar cognitive compromise has been observed in post-traumatic stress disorder (PTSD) patients, and PTSD symptoms are a frequent concomitant of cancer diagnosis. We tested the hypothesis that pretreatment cognitive impairment is attributable to cancer-related post-traumatic stress. METHODS: Women aged 65 years or younger who were diagnosed with breast cancer (case patients) or had undergone negative routine breast imaging (control patients) at one of six participating breast centers underwent traditional and computerized neuropsychological testing, clinician-administered diagnostic assessment of stress disorders, and self-report assessments of cognitive function and depression. To minimize confounding, case patients were evaluated prior to any local or systemic treatment. Cognitive indices of case patients, control patients, and normative samples were compared. The patients' risk of overall cognitive impairment was determined. Linear regression and a mediation model were used to test the study hypothesis. All statistical tests were two-sided. RESULTS: The 166 case patients and 60 well-matched control patients showed near-identical deviations from population norms. Case patients scored worse than control patients on two of 20 cognitive indices (Go/Nogo commission errors, Go/Nogo omission errors). Self-reported cognitive problems were associated with Go/Nogo omission errors and more pronounced in case patients. Only PTSD symptoms (Beta = 0.27, P = .004) and age (Beta = 0.22, P = .04) statistically significantly predicted Go/Nogo errors. The effect of having cancer on Go/Nogo errors was mediated by PTSD symptoms. Case patients did not have an increased risk of overall cognitive impairment. CONCLUSION: Prior to any treatment, breast cancer patients may show limited cognitive impairment that is apparently largely caused by cancer-related post-traumatic stress.