Quality of life of irradiated brain tumor survivors treated with donepezil or placebo: Results of the WFU CCOP research base protocol 91105

Interventions for preventing and ameliorating cognitive deficits in adults treated with cranial irradiation

BACKGROUND

Cognitive deficits are common in people who have received cranial irradiation and have a serious impact on daily functioning and quality of life. The benefit of pharmacological and non-pharmacological treatment of cognitive deficits in this population is unclear. This is an updated version of the original Cochrane Review published in Issue 12, 2014.

OBJECTIVES

To assess the effectiveness of interventions for preventing or ameliorating cognitive deficits in adults treated with cranial irradiation.

SEARCH METHODS

For this review update we searched the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE via Ovid, Embase via Ovid, and PsycInfo via Ovid to 12 September 2022.

SELECTION CRITERIA

We included randomised controlled (RCTs) trials that evaluated pharmacological or non-pharmacological interventions in cranial irradiated adults, with objective cognitive functioning as a primary or secondary outcome measure.

DATA COLLECTION AND ANALYSIS

Two review authors (MK, JD) independently extracted data from selected studies and carried out a risk of bias assessment. Cognitive function, fatigue and mood outcomes were reported. No data were pooled.

MAIN RESULTS

Eight studies met the inclusion criteria and were included in this updated review. Six were from the original version of the review, and two more were added when the search was updated. Nineteen further studies were assessed as part of this update but did not fulfil the inclusion criteria. Of the eight included studies, four studies investigated "prevention" of cognitive problems (during radiotherapy and follow-up) and four studies investigated "amelioration" (interventions to treat cognitive impairment as a late complication of radiotherapy). There were five pharmacological studies (two studies on prevention and three in amelioration) and three non-pharmacological studies (two on prevention and one in amelioration). Due to differences between studies in the interventions being evaluated, a meta-analysis was not possible.  Studies in early radiotherapy treatment phase (five studies) Pharmacological studies in the "early radiotherapy treatment phase" were designed to prevent or ameliorate cognitive deficits and included drugs used in dementia (memantine) and fatigue (d-threo-methylphenidate hydrochloride). Non-pharmacological studies in the "early radiotherapy treatment phase" included a ketogenic diet and a two-week cognitive rehabilitation and problem-solving programme.  In the memantine study, the primary cognitive outcome of memory at six months did not reach significance, but there was significant improvement in overall cognitive function compared to placebo, with similar adverse events across groups. The d-threo-methylphenidate hydrochloride study found no statistically significant difference between arms, with few adverse events. The study of a calorie-restricted ketogenic diet found no effect, although a lower than expected calorie intake in the control group complicates interpretation of the results.  The study investigating the utility of a rehabilitation program did not carry out a statistical comparison of cognitive performance between groups.  Studies in delayed radiation or late effect phase (four studies) The "amelioration" pharmacological studies to treat cognitive complications of radiotherapy included drugs used in dementia (donepezil) or psychostimulants (methylphenidate and modafinil). Non-pharmacological measures included cognitive rehabilitation and problem solving (Goal Management Training). These studies included patients with cognitive problems at entry who had "stable" brain cancer.  The donepezil study did not find an improvement in the primary cognitive outcome of overall cognitive performance, but did find improvement in an individual test of memory, compared to placebo; adverse events were not reported. A study comparing methylphenidate with modafinil found improvements in cognitive function in both the methylphenidate and modafinil arms; few adverse events were reported. Another  study comparing two different doses of modafinil combined treatment arms and found improvements across all cognitive tests, however, a number of adverse events were reported. Both studies were limited by a small sample size. The Goal Management Training study suggested a benefit of the intervention, a behavioural intervention that combined mindfulness and strategy training, on executive function and processing speed.  There were a number of limitations across studies and few were without high risks of bias.

AUTHORS' CONCLUSIONS

In this update, limited additional evidence was found for the treatment or amelioration of cognitive deficits in adults treated with cranial irradiation. As concluded in the original review, there is supportive evidence that memantine may help prevent cognitive deficits for adults with brain metastases receiving cranial irradiation. There is supportive evidence that donepezil, methylphenidate and modafinil may have a role in treating cognitive deficits in adults with brain tumours who have been treated with cranial irradiation; patient withdrawal affected the statistical power of these studies. Further research that tries to minimise the withdrawal of consent, and subsequently reduce the requirement for imputation procedures, may offer a higher certainty of evidence. There is evidence from only a single small study to support non-pharmacological interventions in the amelioration of cognitive deficits. Further research is required.

Interventions for the management of fatigue in adults with a primary brain tumour

BACKGROUND

Fatigue is a common and disabling symptom in people with a primary brain tumour (PBT). The effectiveness of interventions for treating clinically significant levels of fatigue in this population is unclear. This is an updated version of the original Cochrane Review published in Issue 4, 2016.

OBJECTIVES

To assess the effectiveness and safety of pharmacological and non-pharmacological interventions for adults with PBT and clinically significant (or high levels) of fatigue.

SEARCH METHODS

For this updated review, we searched CENTRAL, MEDLINE and Embase, and checked the reference lists of included studies in April 2022. We also searched relevant conference proceedings, and ClinicalTrials.gov for ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that investigated any pharmacological or non-pharmacological intervention in adults with PBT and fatigue, where fatigue was the primary outcome measure. We restricted inclusion specifically to studies that enrolled only participants with clinically significant levels of fatigue to improve the clinical utility of the findings.

DATA COLLECTION AND ANALYSIS

Two review authors (JD, DC) independently evaluated search results for the updated search. Two review authors (JD, SYK) extracted data from selected studies, and carried out a risk of bias assessment. We extracted data on fatigue, mood, cognition, quality of life and adverse events outcomes.

MAIN RESULTS

The original review identified one study and this update identified a further two for inclusion. One study investigated the use of modafinil, one study the use of armodafinil and one study the use of dexamfetamine. We identified three ongoing studies. In the original review, the single eligible trial compared modafinil to placebo for 37 participants with a high- or low-grade PBT. One new study compared two doses of armodafinil (150 mg and 250 mg) to placebo for 297 people with a high-grade glioma. The second new study compared dexamfetamine sulfate to placebo for 46 participants with a low- or high-grade PBT. The evidence was uncertain for both modafinil and dexamfetamine regarding fatigue outcome measures, compared to controls, at study endpoint. Two trials did not reach the planned recruitment target and therefore may not, in practice, have been adequately powered to detect a difference. These trials were at a low risk of bias across most areas. There was an unclear risk of bias related to the use of mean imputation for one study because the investigators did not analyse the impact of imputation on the results and information regarding baseline characteristics and randomisation were not clear. The certainty of the evidence measured using GRADE was very low across all three studies. There was one identified study awaiting classification once data are available, which investigated the feasibility of 'health coaching' for people with a PBT experiencing fatigue. There were three ongoing studies that may be eligible for an update of this review, all investigating a non-pharmacological intervention for fatigue in people with PBT.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to draw reliable and generalisable conclusions regarding potential effectiveness or harm of any pharmacological or non-pharmacological treatments for fatigue in people with PBT. More research is needed on how best to treat people with brain tumours with high fatigue.

Impaired neurocognitive function in glioma patients: from pathophysiology to novel intervention strategies

PURPOSE OF REVIEW

This review succinctly summarizes the recent literature regarding etiological contributors to impaired neurocognitive function (NCF) in adult patients with glioma. A brief overview of intervention and prevention strategies is also provided.

RECENT FINDINGS

A majority of patients with glioma exhibit NCF deficits, most frequently in memory and executive functioning. Impairments are often disabling and associated with reduced quality of life and survival. Cause is multifactorial and includes the tumour itself, treatments received and associated comorbidities. Although modern techniques such as brain mapping, dosing modifications and prophylactic medication aim to improve the NCF outcomes following neurosurgical resection and radiation therapy, a sizeable proportion of patients continue to evidence treatment-related NCF declines related to adverse effects to both local and distributed cerebral networks. Numerous patient and tumour characteristics, including genetic markers and sociodemographic factors, influence the pattern and severity of NCF impairment. Some rehabilitative and pharmacologic approaches show promise in mitigating NCF impairment in this population, though benefits are somewhat modest and larger scale intervention studies are needed.

SUMMARY

Research regarding NCF in patients with glioma has dramatically proliferated, providing insights into the mechanisms underlying impaired NCF and pointing to potential interventions, though further work is needed.

Assessment of Risk of Xerostomia After Whole-Brain Radiation Therapy and Association With Parotid Dose

Importance

Whole-brain radiation therapy (WBRT) delivers a substantial radiation dose to the parotid glands, but the parotid glands are not delineated for avoidance and xerostomia has never been reported as an adverse effect. Minimizing the toxic effects in patients receiving palliative treatments, such as WBRT, is crucial.

Objective

To assess whether xerostomia is a toxic effect of WBRT.

Design, Setting, and Participants

This observational cohort study enrolled patients from November 2, 2015, to March 20, 2018, at 1 academic center (University of North Carolina Hospitals) and 2 affiliated community hospitals (High Point Regional Hospital and University of North Carolina Rex Hospital). Adult patients (n = 100) receiving WBRT for the treatment or prophylaxis of brain metastases were enrolled. Patients who had substantial baseline xerostomia or did not complete WBRT or at least 1 postbaseline questionnaire were prospectively excluded from analysis and follow-up. Patients received 3-dimensional WBRT using opposed lateral fields covering the skull and the C1 or C2 vertebra. Per standard practice, the parotid glands were not prospectively delineated.

Main Outcomes and Measures

Patients completed the University of Michigan Xerostomia Questionnaire and a 4-point bother score at baseline, immediately after WBRT, at 1 month, at 3 months, and at 6 months. The primary end point was the 1-month xerostomia score, with a hypothesized worsening score of 10 points from baseline.

Results

Of the 100 patients enrolled, 73 (73%) were eligible for analysis and 55 (55%) were evaluable at 1 month. The 73 patients included 43 women (59%) and 30 men (41%) with a median (range) age of 61 (23-88) years. The median volume of parotid receiving at least 20 Gy (V20Gy) was 47%. The mean xerostomia score was 7 points at baseline and was statistically significantly higher at each assessment period, including 21 points immediately after WBRT (95% CI, 16-26; P < .001), 23 points (95% CI, 16-30; P < .001) at 1 month, 21 points (95% CI, 13-28; P < .001) at 3 months, and 14 points (95% CI, 7-21; P = .03) at 6 months. At 1 month, the xerostomia score increased by 20 points or more in 19 patients (35%). The xerostomia score at 1 month was associated with parotid dose as a continuous variable and was 35 points in patients with parotid V20Gy of 47% or greater, compared with only 9 points in patients with parotid V20Gy less than 47% (P < .001). The proportion of patients who self-reported to be bothered quite a bit or bothered very much by xerostomia at 1 month was 50% in those with parotid V20Gy of 47% or greater, compared with only 4% in those with parotid V20Gy less than 47% (P < .001). At 3 months, this difference was 50% vs 0% (P = .001). Xerostomia was not associated with medication use.

Conclusions and Relevance

Clinically significant xerostomia occurred by the end of WBRT, appeared to be persistent, and appeared to be associated with parotid dose. The findings from this study suggest that the parotid glands should be delineated for avoidance to minimize these toxic effects in patients who undergo WBRT and often do not survive long enough for salivary recovery.

Cognitive functioning following brain irradiation as part of cancer treatment: Characterizing better cognitive performance

OBJECTIVE

Although brain radiation therapy (RT) impacts cognitive function, little is known about the subset of survivors with minimal cognitive deficits. This study compares the characteristics of patients receiving brain irradiation as part of cancer treatment with minimal cognitive deficits to those with poorer cognitive functioning.

METHODS

Adults at least 6 months postbrain RT (N = 198) completed cognitive measures of attention, memory, and executive functions. Cognitive functioning was categorized into better- and poorer-performing groups, with better-performing survivors scoring no worse than 1.5 standard deviations below the published normative mean on all cognitive measures. Logistic regression was used to identify variables associated with better-performing group membership.

RESULTS

Approximately 25% of the sample met the criteria for the better-performing group. In unadjusted analyses, RT type (whole brain irradiation and partial brain irradiation), sedating medications, and fatigue were independently associated with cognition. Sociodemographic and other clinical characteristics were not significant. In adjusted analyses, only fatigue remained significantly associated with group membership (OR = 1.05, 95% CI = 1.01-1.09, P = .009).

CONCLUSIONS

There is a subgroup of survivors with minimal long-term cognitive deficits despite undergoing a full course of brain RT as part of cancer treatment. Lower fatigue had the strongest association with better cognitive performance. Interventions targeting cancer-related fatigue may help buffer the neurotoxic effects of brain RT.

Treatment of Radiation-Induced Cognitive Decline in Adult Brain Tumor Patients

OPINION STATEMENT

Patients with either primary or metastatic brain tumors quite often have cognitive impairment. Maintaining cognitive function is important to brain tumor patients and a decline in cognitive function is generally accompanied by a decline in functional independence and performance status. Cognitive decline can be a result of tumor progression, depression/anxiety, fatigue/sleep dysfunction, or the treatments they have received. It is our opinion that providers treating brain tumor patients should obtain pre-treatment and serial cognitive testing in their patients and offer mitigating and therapeutic interventions when appropriate. They should also support cognition-focused clinical trials.