Cancer-induced cognitive impairment: practical solutions to reduce and manage the challenge

Improve the management of cancer-related cognitive impairment in clinical settings: a European Delphi study

PURPOSE

Cancer-related cognitive impairment (CRCI) is under-addressed by healthcare professionals owing to a lack of clinical management guidelines. This European Delphi study proposes recommendations to healthcare professionals for the management of CRCI in patients with non-central nervous system (non-CNS) cancers.

METHODS

Twenty-two recommendations were developed based on a literature review and authors' clinical experience, split into three categories: screening, cognitive assessment, intervention. The survey included European professionals, experts in CRCI. The Delphi method was used: experts rated the clinical relevancy of recommendations on a 9-point Likert scale in three rounds. A recommendation was accepted if all votes were between 7 and 9. Recommendations not accepted in round 1 and round 2 were deleted, or modified and rated in round 3.

RESULTS

Eighteen professionals (psychologists, physicians, researchers) voted and accepted 15 recommendations. Experts recommended the systematic screening of CRCI, followed by a short objective cognitive assessment, if complaints screened. A comprehensive evaluation is recommended if CRCI persists 6 months post-treatment. Cognitive rehabilitation, physical activity, meditative-movement therapy, and multimodal intervention should be offered. Recommendations about frequency and duration of interventions, the professional to administer cognitive rehabilitation and the use of meditation and cognitive training without psychoeducation were not accepted.

CONCLUSIONS

This survey provides 15 recommendations to assist healthcare professionals in detecting, assessing and offering interventions for CRCI.

IMPLICATIONS FOR CANCER SURVIVORS

These recommendations should be included in supportive care to help healthcare professionals to detect CRCI and propose the best available intervention for patients with cognitive complaints. Developing CRCI management in clinical settings would improve patients' quality of life.

The Effect of Walking Intervention on Cognitive Function Among Patients With Non-Central Nervous System Cancer: A Systematic Review

BACKGROUND

Cognitive impairment is one of the most frequently reported symptoms in patients with non-central nervous system (non-CNS) cancer. Walking has positive effects on cognitive function. However, the effects of walking interventions on cognitive function outcomes in patients with non-CNS cancer are not well synthesized.

OBJECTIVE

The aim of this study was to explore the characteristics of walking intervention and its effects on cognitive function in patients with non-CNS cancer.

METHODS

Ten databases were searched to identify eligible randomized controlled trials from each database's inception to June 7, 2021. The Physiotherapy Evidence Database Scale was used to assess the quality of the included studies.

RESULTS

Five randomized controlled trials involving 242 adults with non-CNS cancer were included. Two studies involving immediate treadmill walking interventions with moderate intensity at 40% to 60% maximal heart rate reported significantly improved objective cognitive domains of processing speed and spatial working memory with small to moderate effect sizes for cancer survivors. One study delivering home-based, moderate-intensity walking intervention had borderline significantly positive effects on perceived cognitive functioning for patients with non-CNS cancer during chemotherapy.

CONCLUSION

Walking intervention with moderate intensity is a beneficial approach to improve objective cognitive domains of processing speed and spatial working memory and perceived cognitive function.

IMPLICATIONS FOR PRACTICE

Nurses may provide moderate-intensity walking with 40% to 60% maximal heart rate monitoring to alleviate cognitive problems during the continuous process of cancer care. The modality and dosage of intervention should be adjusted depending on this population's tolerance to better maintain training.

A Telehealth-Based Cognitive-Adaptive Training (e-OTCAT) to Prevent Cancer and Chemotherapy-Related Cognitive Impairment in Women with Breast Cancer: Protocol for a Randomized Controlled Trial

Background: Many women with breast cancer experience a great number of side effects, such as cognitive impairment, during and after chemotherapy that reduces their quality of life. Currently, research focusing on the use of non-pharmacological, and specifically telehealth interventions to prevent or mitigate them has been insufficient. Methods: This protocol describes a randomized controlled trial aimed at studying the preventive effects of a videoconferenced cognitive-adaptive training (e-OTCAT) program (ClinicalTrials.gov NCT04783402). A number of 98 eligible participants will be randomized to one of the following groups: (a) the experimental group receiving the e-OTCAT program during 12 consecutive weeks since the beginning of chemotherapy; and (b) the control group receiving and educational handbook and usual care. The primary outcome will be the cognitive function. Secondary measures will be psychological distress, fatigue, sleep disturbance, quality of life and occupational performance. The time-points for these measures will be placed at baseline, after 12 weeks and six months of post-randomization. Conclusion: This trial may support the inclusion of multidimensional interventions through a telehealth approach in a worldwide growing population suffering from breast cancer, emphasizing the prevention of cognitive impairment as one of the side effects of cancer and its treatments.

Australian oncology health professionals' knowledge, perceptions, and clinical practice related to cancer-related cognitive impairment and utility of a factsheet

PURPOSE

Cancer-related cognitive impairment (CRCI) can have debilitating effects on cancer survivors' quality of life. Despite this, patients often report a lack of information provided by health professionals (HPs) to assist with understanding and managing cognitive changes. This study aimed to explore Australian oncology HPs' understanding of and clinical practice related to CRCI including the use of a Cancer Council Australia CRCI factsheet.

METHODS

Australian oncology HPs (medical oncologists, cancer nurses, and clinical psychologists) completed a questionnaire that assessed CRCI knowledge, prior to receiving the factsheet. Semi-structured interviews were conducted to explore their perceptions of CRCI and the factsheet. Interviews were recorded, transcribed, and analyzed using framework analysis to identify key themes.

RESULTS

Questionnaires were completed by twenty-nine HPs. Most HPs had moderate to high knowledge of CRCI, yet low knowledge of the relationship between CRCI and cancer. Twenty-six (response rate 90%) HPs; medical oncologists (n = 7), cancer nurses (n = 12), and clinical psychologists (n = 7), consented to be interviewed. Three main themes were identified: (1) Is CRCI impact real or over-rated?; (2) If it is important, they will tell me: identifying and responding to CRCI in clinical practice; and (3) Using a factsheet in clinical practice.

CONCLUSION

This study's multi-disciplinary exploration of Australian oncology HPs' perceptions of CRCI highlighted that health professional perceptions drive CRCI discussions with patients. Further education to support clinicians to discuss CRCI is required. Consideration of the barriers and facilitators within healthcare settings is important for successful integration of the factsheet into routine care.

Long-Term Cognitive Dysfunction in Cancer Survivors

Cancer-related cognitive impairment (CRCI) is a frequent side effect experienced by an increasing number of cancer survivors with a significant impact on their quality of life. Different definitions and means of evaluation have been used in available literature; hence the exact incidence of CRCI remains unknown. CRCI can be described as cognitive symptoms reported by cancer patients in self-reported questionnaires or as cognitive changes evaluated by formal neuropsychological tests. Nevertheless, association between cognitive symptoms and objectively assessed cognitive changes is relatively weak or absent. Studies have focused especially on breast cancer patients, but CRCI has been reported in multiple types of cancer, including colorectal, lung, ovarian, prostate, testicular cancer and hematological malignancies. While CRCI has been associated with various treatment modalities, including radiotherapy, chemotherapy, hormone therapy and novel systemic therapies, it has been also detected prior to cancer treatment. Therefore, the effects of cancer itself with or without the psychological distress may be involved in the pathogenesis of CRCI as a result of altered coping mechanisms after cancer diagnosis. The development of CRCI is probably multifactorial and the exact mechanisms are currently not completely understood. Possible risk factors include administered treatment, genetic predisposition, age and psychological factors such as anxiety, depression or fatigue. Multiple mechanisms are suggested to be responsible for CRCI, including direct neurotoxic injury of systemic treatment and radiation while other indirect contributing mechanisms are hypothesized. Chronic neuroinflammation mediated by active innate immune system, DNA-damage or endothelial dysfunction is hypothesized to be a central mechanism of CRCI pathogenesis. There is increasing evidence of potential plasma (e.g., damage associated molecular patterns, inflammatory components, circulating microRNAs, exosomes, short-chain fatty acids, and others), cerebrospinal fluid and radiological biomarkers of cognitive dysfunction in cancer patients. Discovery of biomarkers of cognitive impairment is crucial for early identification of cancer patients at increased risk for the development of CRCI or development of treatment strategies to lower the burden of CRCI on long-term quality of life. This review summarizes current literature on CRCI with a focus on long-term effects of different cancer treatments, possible risk factors, mechanisms and promising biomarkers.

Neurocognitive Effects of Chemotherapy for Colorectal Cancer: A Systematic Review and a Meta-Analysis of 11 Studies

Purpose

Chemotherapy-related cognitive impairment (CRCI) is a controversial concept not much explored on colorectal cancer patients.

Materials and Methods

We identified 11 prospective studies: eight studies on 696 colorectal cancer patients who received chemotherapy and three studies on 346 rectal cancer patients who received neoadjuvant chemoradiotherapy. Standardized mean differences (SMDs) of neuropsychological test results and the cognitive quality-of-life scale were calculated using random effect models. A meta-regression was conducted to investigate the association between mean study population age and effect sizes.

Results

The association between chemotherapy and cognitive impairment was not clear in colorectal cancer patients (SMD, 0.003; 95% confidence interval, −0.080 to 0.086). However, a meta-regression showed that older patients are more vulnerable to CRCI than younger patients (β=–0.016, p < 0.001).

Conclusion

Chemotherapy has an overall positive negligible effect size on the cognitive function of colorectal patients. Age is a significant moderator of CRCI.

Falls and Cancer

Falls among older people are common and are associated with substantial morbidity, mortality and healthcare costs. Increasingly cancer is becoming a disease of older people and fall rates are higher in elders living with cancer. Cancer and its treatments potentiate important risk factors for falls, including muscle weakness, poor balance, proprioception, cognitive impairment and functional disability. Sarcopenia refers to the progressive deterioration in muscle strength, mass and quality with ageing. Chronic conditions and cancer amplify this decline and are associated with a greater negative effect on function. Age-related impairments of lower limb neurological function are commonly exacerbated by neurotoxic chemotherapy, resulting in gait and balance deficits. Postural instability and falls erode confidence and result in a negative cycle of diminishing activity levels, further deconditioning and a higher risk of further falls. Cancer-related fatigue, sleep and mood disturbances compound this progressive frailty, further worsening treatment tolerance and outcomes. Cognitive impairment is a potent risk factor for falling and is frequently associated with gait abnormalities. The well-recognised effects of cancer treatment on working memory, attention, processing speed and executive function are often apparent (when their presence is sought) before treatment and may be as much the result of the cancer itself as they are 'chemo brain'. Structured exercise programmes focusing on progressively challenging strength and balance training are of proven benefit in falls prevention. Regular aerobic exercise accrues additional benefits in improved cardiorespiratory resilience and concomitant positive effects on treatment tolerance. Increased activity levels positively influence cognition, mood and foster an improved sense of well-being. Simple, practicable clinic-based tests of physical functioning, cognition and neurological function can help to identify those at high risk of falls and functional decline. The use of such instruments can aid judicious treatment planning and identify those most likely to benefit from more detailed specialist comprehensive geriatric assessment.

Systematic review of cognitive sequelae of non-central nervous system cancer and cancer therapy

PURPOSE

The aim of this review is to provide an updated overview of chemotherapy-related cognitive impairment (CRCI) in patients with cancer outside central nervous system (CNS), its incidence and prevalence, the cognitive pattern in neuropsychological studies, neuroimaging findings, and the relationship between chemobrain and aging. Methodological limitations of studies are also discussed.

METHODS

This review was guided by the PRISMA statement. The MEDLINE and Scopus databases were employed to search articles about CRCI in non-CNS cancer patients published from January 2004 to September 2019. Two types of research were reviewed: prospective studies addressing the effects of chemotherapy on cognition and systematic reviews about factors related with CRCI, also as neuroimaging findings and current available treatments.

RESULTS

Fifty-nine studies meeting the criteria were analyzed: 47 were longitudinal studies on cancer and cognition and 12 were reviews on risk factors, neuroimaging, and treatment. The majority of studies find cognitive impairment in patients with cancer treated with chemotherapy. The body of the literature on breast cancer is the most abundant, but there are also studies on colorectal, testicular, and lung cancer. Neuroimaging studies show changes in structure and activation in patients undergoing chemotherapy. Non-pharmacological treatment is effective for improving cognition and quality of life.

CONCLUSIONS

The occurrence of CRCI during the course of treatment in people with different types of cancer is frequent. Some risk factors have been identified, but CRCI is a complex phenomenon, with mediating factors related to cancer and treatment and moderating factors related with lifestyle and health.

IMPLICATIONS FOR CANCER SURVIVORS

This review highlights the importance of recognizing that this cognitive dysfunction is frequent, mild to moderate in nature but with great impact on quality of life.

Adaptations to cognitive problems reported by breast cancer survivors seeking cognitive rehabilitation: A qualitative study

OBJECTIVE

Qualitative studies have elucidated cancer survivors' experiences of cognitive changes associated with cancer and cancer treatment. This study specifically explored experiences of women treated for breast cancer who were seeking cognitive rehabilitation. The objective was to characterise the frequency and nature of cognitive changes and adaptations to cognitive change reported by these participants to better understand treatment needs of this group.

METHOD

Australian women who had completed primary treatments for breast cancer (surgery, chemotherapy, and/or radiotherapy) and volunteered to participate in one of two cognitive rehabilitation intervention studies were interviewed via telephone. Interview responses regarding cognitive changes and adaptations to cognitive change were transcribed by the interviewers, then coded and analysed by two researchers using content analysis.

RESULTS

Among the 95 participants (age M=54.3 years, SD=9.6), the most commonly reported cognitive change was memory (79% of participants) and 61% reported more than one type of cognitive change. Adaptations to change were reported by 87% of participants, with written or electronic cues the most common (51%). Most often, participants reported using a single type of adaptation (48%) with only 39% reporting multiple types of adaptations.

CONCLUSIONS

Women treated for breast cancer, who were seeking cognitive rehabilitation, most commonly reported memory changes, which were mainly managed through a single type of adaptation. These results suggest that there is considerable scope for increasing the range of cognitive adaptations to improve the quality of life of cancer survivors who experience adverse cognitive changes.

Cognitive complaints in cancer survivors and expectations for support: Results from a web-based survey

Background

Cognitive complaints are common in cancer survivors. We aimed to assess cognitive complaints in cancer survivors and the associated factors using a large web–based survey.

Methods

This online survey was proposed to cancer survivors. Participants completed several questions on cognitive complaints experience, expectations for support of cognitive difficulties, preexisting knowledge about chemotherapy–associated cognitive problems and demographic and medical variables. We used multivariable logistic regression models to estimate Odds Ratios and 95% confidence intervals to estimate associations.

Results

Among 1610 eligible participants (median age 52 [21‐84]), >85% (n = 1393) were breast cancer survivors. Median postcancer treatment time (excluding hormone therapy) was 2.83 years [0.8‐33]. Seventy five percent of the participants (n = 1214) reported cognitive complaints related to cancer treatments. Cognitive difficulties had an impact on work resumption for 76% of the participants (n = 754/982). Most cancer survivors would like to receive support (75%, n = 909) and especially cognitive training (72%, n = 658). Chemotherapy was strongly associated with cognitive complaints (multivariable OR = 3.67, 95% CI: 2.80‐4.82). Self–reported sleep difficulties (OR_{often vs. never} = 2.84, 95% CI: 1.80‐4.47), preexisting knowledge about chemotherapy–associated cognitive problems (OR_{No vs. Yes} = 1.69, 95% CI: 1‐29‐2.22) and age (OR_{21‐64 vs. ≥65} = 0.37, 95% CI: 0.23‐0.58) were also associated with cancer–related cognitive complaints.

Conclusions

According to this large web–based survey including mainly breast cancer survivors, cognitive complaints were reported by three quarters of participants, which reinforces that cognitive difficulties are a major issue in cancer survivors. Chemotherapy, self–reported sleep difficulties and preexisting knowledge about chemotherapy–associated cognitive problems were strongly associated with cancer–related cognitive complaints. Most cancer survivors wished to receive support and especially cognitive training.

How to Identify and Manage Cognitive Dysfunction After Breast Cancer Treatment

Attention and memory dysfunction is a common complaint among patients with breast cancer that can be reported during and up to several years after treatment. It can negatively affect patients' quality of life and their ability to work. This phenomenon has mainly been studied in patients with breast cancer who are treated with adjuvant chemotherapy. Women describe concentration problems and difficulties with word finding, multitasking, or remembering new information, as well as more effort and time needed to accomplish these tasks. Such cognitive dysfunction is subtle or moderate and occurs in 15% to 25% of patients. Older patients seem more likely to experience cognitive decline with chemotherapy than do young women with breast cancer. Patients who report that cognitive dysfunction has affected their daily lives for 6 to 12 months after the end of chemotherapy or during hormone therapy may need referral to a neuropsychologist. During the cognitive assessment, the etiology of their cognitive complaints is sought and neuropsychological tests are administered to assess objective cognitive functioning. Psychological factors-fatigue and pain-should be assessed systematically with cognitive complaints to identify precisely the cause of the problems. A nonpharmacologic approach-mainly cognitive rehabilitation-seems to be the most promising for the management of these difficulties, but these preliminary results require confirmation. In the future, early detection of cognitive impairment and cognitive rehabilitation should be included in the portfolio of oncology supportive care to facilitate the return to work of young women and to avoid potential repercussions on adherence to oral treatments and on autonomy in older patients.

Cognitive Changes After Adjuvant Treatment in Older Adults with Early-Stage Breast Cancer

BACKGROUND

Group-based trajectory modeling is particularly important to identify subgroups of patients with pathological cognitive changes after cancer treatment. To date, only one study has explored cognitive trajectories in older patients with cancer. The present article describes objective cognitive changes before to after adjuvant treatment in older adults with early-stage breast cancer (EBC) after adjuvant treatment compared with healthy controls.

PATIENTS AND METHODS

Participants were patients ≥65 years of age with newly diagnosed EBC and healthy controls (age-, sex-, and education-matched). The pretreatment assessment was conducted before adjuvant therapy, and the post-treatment assessment after the end of the first adjuvant treatment. Objective cognitive changes before to after treatment were evaluated based on the Reliable Change Index for cognitive decline accounting for cognitive impairment status.

RESULTS

The sample consisted of women newly diagnosed with EBC (n = 118) and healthy controls (n = 62). Five patterns of changes before to after treatment were identified based on the presence of cognitive decline and cognitive impairment. The distribution of these five change patterns was statistically significant (p = .0001). Thirty-six percent of patients had phase shift changes, 31% without initial objective cognitive impairment developed impairment, 15% had a normal aging, 12% had a nonpathological decline, and 6% experienced accelerated cognitive decline.

CONCLUSION

This study described for the first time objective cognitive changes before to after treatment of older adults with EBC immediately after the end of adjuvant treatment. A longer-term remote follow-up of adjuvant treatment is needed to better understand the cognitive trajectories of older patients with EBC.

IMPLICATIONS FOR PRACTICE

After the end of adjuvant treatment, 31% of older adults with early-stage breast cancer without initial objective cognitive impairment developed impairment, and 6% experienced accelerated cognitive decline. Initial cognitive functioning should be included in the balance of benefits and harms of systemic therapy for patients who are likely to be at highest risk for cognitive decline after cancer treatments. Regular cognitive follow-up of patients who had cognitive impairment before cancer treatment should monitor symptoms suggestive of neurodegenerative disease and avert the effect of cognitive disorders on patients' autonomy.