Theory of mind deficit in women with breast cancer and depression: A comparative study

Background: Studies have established that Theory of Mind (ToM) is impaired in patients with depression, but few studies have investigated the status of ToM in breast cancer patients who often suffer from depression. Our objective was to compare the ToM deficits in women with breast cancer with and without depression with a control group. Methods: The study was conducted at the Oncology department of a multi-speciality hospital in Kolkata. It was a cross sectional matched control study. We compared the ToM performance of women with breast cancer and depression (N=39), breast cancer without depression (N=63) and a healthy control group (N=34) using the widely used ToM task, Reading the Mind in the Eyes test (Eyes Test). Depression was diagnosed using Mini - International Neuropsychiatric Interview following International Classification of Diseases - 10th edition guidelines. Chi-square and one-way analysis of variances was done. Results: Both groups of patients had greater impairment in ToM compared to healthy controls (p<0.05). Among breast cancer patients, presence of depression predicted even greater impairment of ToM (p<0.05). Lower income, less education and not being in any occupation other than homemaking were associated with greater ToM impairment across all groups (p<0.05). Conclusion: Breast cancer patients suffering from depression may have an additional burden of impaired social cognition, which may reduce their ability to shore up social support when it is most required. This needs to be addressed urgently to ensure better quality of life.