Abstract
BackgroundCognitive impairment is commonly reported in patients receiving chemotherapy, but the acuity of onset is not known. This study utilized the psychomotor vigilance test (PVT) and trail-making test B (TMT-B) to assess cognitive impairment immediately post-chemotherapy.MethodsPatients aged 18–80 years receiving first-line intravenous chemotherapy for any stage of breast or colorectal cancer were eligible. Patient symptoms, peripheral neuropathy and Stanford Sleepiness Scale were assessed. A five-minute PVT and TMT-B were completed on a tablet computer pre-chemotherapy and immediately post-chemotherapy. Using a mixed linear regression model, changes in reciprocal transformed PVT reaction time (mean 1/RT) were assessed. A priori, an increase in median PVT reaction times by > 20 ms (approximating PVT changes with blood alcohol concentrations of 0.04–0.05 g%) was considered clinically relevant.ResultsOne hundred forty-two cancer patients (73 breast, 69 colorectal, median age 55.5 years) were tested. Post-chemotherapy, mean 1/RT values were significantly slowed compared to pre-chemotherapy baseline (p = 0.01). This corresponded to a median PVT reaction time slowed by an average of 12.4 ms. Changes in PVT reaction times were not correlated with age, sex, cancer type, treatment setting, or use of supportive medications. Median post-chemotherapy PVT reaction time slowed by an average of 22.5 ms in breast cancer patients and by 1.6 ms in colorectal cancer patients. Post-chemotherapy median PVT times slowed by > 20 ms in 57 patients (40.1%). Exploratory analyses found no statistically significant association between the primary outcome and self-reported anxiety, fatigue or depression. TMT-B completion speed improved significantly post-chemotherapy (p = 0.03), likely due to test-retest phenomenon.ConclusionsPVT reaction time slowed significantly immediately post-chemotherapy compared to a pre-chemotherapy baseline, and levels of impairment similar to effects of alcohol consumption in other studies was seen in 40% of patients. Further studies assessing functional impact of cognitive impairment on patients immediately after chemotherapy are warranted.
Highlights
Cognitive impairment is commonly reported in patients receiving chemotherapy, but the acuity of onset is not known
Psychomotor vigilance test Compared to a pre-chemotherapy baseline, the mean reciprocal transformed psychomotor vigilance test (PVT) reaction time was significantly slowed post-chemotherapy (p = 0.01)
Median PVT reaction time slowed by an average of 22.4 ms, while colorectal cancer patients experienced slowing of their median PVT reaction time by an average of 1.6 ms
Summary
Cognitive impairment is commonly reported in patients receiving chemotherapy, but the acuity of onset is not known. In 2007, the estimated prevalence of chemotherapy treatment was nearly 650,000 individuals, with each patient having, on average, 11 annual visits during which chemotherapy was administered [2]. Cancer survivors commonly report cognitive decline after chemotherapy. This entity, often referred to as ‘chemo-brain’ or ‘chemo-fog’ [3], is described in anywhere from 17 to 78% of breast cancer patients [4]. No clear predictors of cognitive impairment after chemotherapy are currently identified [4], though older age, lower cognitive reserve and increasing chemotherapy dosage/duration are associated with cognitive decline in some studies [3, 5]. Multiple studies have shown an independent effect on cognition even after accounting for anxiety, fatigue, depression or menopause [6,7,8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
