Systematic review of longitudinal studies on chemotherapy‐associated subjective cognitive impairment in cancer patients

Abstract

Objectives: This systematic review of longitudinal studies, assessing subjective cognitive impairment (SCI) reported by adult cancer patients, aimed to summarize evidence on the impact of chemotherapy on SCI, identify moderators of SCI, and evaluate methodological issues. Methods: Data accrued from Pubmed, EMBASE, CINAHL, PsychInfo, and the Cochrane library. Inclusion criteria were original studies, an exclusively adult sample, valid and reliable subjective cognitive measures, and at least one baseline data point prior to and another after the initiation of chemotherapy. Data were collected on the sample composition, data-collection time points, outcome measures, statistical analysis, and major findings (ie, longitudinal changes in prevalence, severity, and associated factors).Results: Forty articles published between 2004 and 2019 were retained: 21 examined chemotherapy-treated patients only, and 19 employed control groups. Findings were mixed, with slightly more studies supporting the impact of chemotherapy on SCI. SCI tended to be more prevalent and severe after initiating chemotherapy, compared with patients' own baseline and controls not treated with chemotherapy. Impact appeared to be acute and more likely limited to subsamples. Most studies examining non-breast-cancer samples reported the lack or limited impact of chemotherapy on SCI. The most consistent moderators were depression and fatigue. Methodological issues regarding sampling design, measurement, and statistical analysis were discussed.Conclusion: More rigorously designed longitudinal studies would clarify direct and indirect effects of chemotherapy on SCI. K E Y W O R D S anxiety, cancer, cognitive function, cognitive impairment, depression, fatigue, oncology, systematic review

Perceived Cognitive Impairment in Breast Cancer Survivors and Its Relationships with Psychological Factors

“…In a recent prospective longitudinal study, cancer survivors treated with chemotherapy reported more cognitive complaints than matched healthy controls [ 9 ]. Chemotherapy induced subjective cognitive impairment was not only more frequent, but also more severe than in patients not treated with chemotherapy [ 1 ]. In the TAILORx study, Wagner et al reported that cognitive subjective decline secondary to chemotherapy seemed to be early and acute, but did not worsen over time [ 21 ].…”

“…The quality of life, in particular the “post-cancer” quality of life, is becoming one of the priorities. Cognitive complaints are an adverse effect frequently reported by cancer patients, especially after chemotherapy [ 1 ]. Fifteen to fifty percent of breast cancer survivors report cognitive dysfunctions [ 2 ].…”

“…Psychological factors can also be associated with cognitive complaints [ 9 ]. Anxiety, depression or fatigue are now well-known modifiable risk factors [ 1 , 10 ]. However, the association with post-traumatic stress symptoms has been less studied.…”

Self‐reported cognitive outcomes among adolescent and young adult patients with noncentral nervous system cancers

“…Extensive research has been performed in order to evaluate CRCI in single tumor type cohorts, for example, breast and colorectal cancer patients. However, the mean ages of the study subjects in these studies are generally much higher than the adolescent and young adult (AYA) age range, 2,3 which encompasses cancer patients between the ages of 15 and 39 years old, as defined by the Institute of Medicine 4 . Even among cancers that are common within the AYA age range, such as Hodgkin's lymphoma 5 and testicular cancer, 6 representation of AYA patients is often low, and subgroup analysis of AYA patients has not been presented in the literature.…”

Determinants of the Higher Prevalence and Severity of Subjective Cognitive Impairment in Cancer Patients Compared to Healthy Subjects: Fatigue and Stress

“…As stress, fatigue, and sleep disturbance all have psychoneurological aspects, we named them psychoneurological factors for convenience. We selected these psychoneurological factors because they are common issues in healthy people and in cancer patients, and previous studies reported their association with SCI in cancer patients (Kim et al, 2020).…”