Systematic review of self-reported cognitive function in cancer patients following chemotherapy treatment.

Purpose: Cognitive symptoms are common in cancer patients, with up to 70% reporting cognitive symptoms following chemotherapy. These symptoms can have a major impact on how an individual functions in all aspects of their lives. This review evaluates self-reported cognitive function and its associations with neuropsychological tests and patient-reported outcomes in adult cancer patients who received chemotherapy treatment for a solid cancer.
Methods: A search of multiple databases (Medline, Ovid at Nursing, PsycINFO, Allied and Complementary Medicine) from 1936 to 2017 was conducted, identifying 1563 unique articles, of which 101 met inclusion criteria.
Results: Of the 101 included studies, 48 (47%) were cross-sectional and 38 (38%) longitudinal in design, with 12 (12%) randomised controlled trials. A minority (26%) incorporated a healthy control arm in the study design, whilst the majority (79%) were in women with breast cancer. There was diversity in the assessment of self-reported cognitive symptoms. A total of 43 of 44 studies that sought an association between self-reported cognitive function and patient-reported outcomes found a moderate to strong association. Overall, 31 studies showed a lack of association between self-reported cognitive symptoms and neuropsychological results, whilst 14 studies reported a significant association between the two, but the association was often restricted to limited cognitive domains.
Conclusion: The review found widespread heterogeneity in the assessment of self-reported cognitive symptoms and consistently absent or weak association with neuropsychological test scores.
Implications for Cancer Survivors: This research highlights the need for a standardised approach to measurement of self-reported cognitive symptoms in cancer patients.