The association of age, body mass index, and frailty with vestibular schwannoma surgical morbidity

Frailty and postoperative outcomes in brain tumor patients: a systematic review subdivided by tumor etiology

PURPOSE

Frailty has gained prominence in neurosurgical oncology, with more studies exploring its relationship to postoperative outcomes in brain tumor patients. As this body of literature continues to grow, concisely reviewing recent developments in the field is necessary. Here we provide a systematic review of frailty in brain tumor patients subdivided by tumor type, incorporating both modern frailty indices and traditional Karnofsky Performance Status (KPS) metrics.

METHODS

Systematic literature review was performed using PRISMA guidelines. PubMed and Google Scholar were queried for articles related to frailty, KPS, and brain tumor outcomes. Only articles describing novel associations between frailty or KPS and primary intracranial tumors were included.

RESULTS

After exclusion criteria, systematic review yielded 52 publications. Amongst malignant lesions, 16 studies focused on glioblastoma. Amongst benign tumors, 13 focused on meningiomas, and 6 focused on vestibular schwannomas. Seventeen studies grouped all brain tumor patients together. Seven studies incorporated both frailty indices and KPS into their analyses. Studies correlated frailty with various postoperative outcomes, including complications and mortality.

CONCLUSION

Our review identified several patterns of overall postsurgical outcomes reporting for patients with brain tumors and frailty. To date, reviews of frailty in patients with brain tumors have been largely limited to certain frailty indices, analyzing all patients together regardless of lesion etiology. Although this technique is beneficial in providing a general overview of frailty's use for brain tumor patients, given each tumor pathology has its own unique etiology, this combined approach potentially neglects key nuances governing frailty's use and prognostic value.

The Influence of Modifiable Risk Factors on Postoperative Outcomes in Patients Receiving Surgery for Resection for Acoustic Neuroma

Acoustic neuromas are the most common tumor of the cerebellopontine angle that are associated with a number of symptoms that negatively impact a patient's quality of life. While the mainstay of treatment for these benign tumors remains microsurgical resection, there is limited research exploring how certain modifiable risk factors (MRFs) may affect the perioperative course. The purpose of this study was to investigate how MRFs including malnutrition, obesity, dyslipidemia, uncontrolled hypertension, and smoking may affect postoperative rates of readmission and nonroutine discharges. We utilized the 2016 and 2017 Healthcare Cost and Utilization Project Nationwide Readmissions Database. MRFs were queried using appropriate International Classification of Diseases, Tenth Revision (ICD-10) coding for categories including malnutrition, obesity, dyslipidemia, smoking, alcohol, and hypertension. The statistical analysis was done using RStudio (Version 1.3.959). Chi-squared tests were done to evaluate differences between categorical variables. The Mann-Whitney U-testing was utilized to evaluate for statistically significant differences in continuous data. The "Epitools" package was used to develop logistic regression models for postoperative complications and post hoc receiver operating characteristic curves were developed. Pertaining to nonroutine discharge, predictive models using malnutrition outperformed all other MRFs as well as those with no MRFs (P < .05). In the case of readmission, models using malnutrition outperformed those of obesity and smoking (P < .05). Again, an increase in predictive power is seen in models using dyslipidemia when compared to obesity, smoking, or uncontrolled hypertension. Lastly, models using no MRFs outperformed those of obesity, smoking, and uncontrolled hypertension (P < .05). This is the first study of its kind to evaluate the role of MRFs in those undergoing surgical resection of their acoustic neuroma. We concluded that certain MRFs may play a role in complicating a patient's perioperative surgical course.

Impact of Obesity on Postoperative Complications after Lateral Skull Base Surgery: A Systematic Review

INTRODUCTION

The relationship between obesity and complications after lateral skull base tumor resection is not clear. There is conflicting evidence regarding the incidence of postoperative complications in this patient population. The purpose of this study is to examine the relationship between obesity and outcomes following lateral skull base tumor resection.

DATA SOURCES

Data were extracted from PubMed, Embase, CINAHL, and Cochrane CENTRAL.

METHODS

Included studies assessed the relationship between obesity and outcomes following lateral skull base tumor removal. Studies with ≤5 patients, pediatric patients, duplicate patient populations, or insufficient data were excluded. Two independent investigators reviewed each study for inclusion. A third reviewer served as a tie-breaker for any conflicts. Extracted data includes patient demographics, tumor pathology, surgical approach, and postoperative outcomes including incidence of cerebrospinal fluid (CSF) leak and other postoperative complications, length of stay (LOS), and readmission and reoperation rates. Descriptive statistics were used to compare postoperative outcomes for obese and nonobese controls.

RESULTS

14 studies met final inclusion criteria. Nine studies evaluated the relationship between obesity and CSF leaks. Four studies found a significant increase in postoperative CSF leak in obese patients compared to nonobese controls. The remaining studies trended toward an increased incidence of CSF leak in the obese population but did not reach statistical significance. One out of seven studies found that obesity increased postoperative LOS, and one out of five studies found that obesity increased reoperation rates following tumor resection.

CONCLUSIONS

Based on the results, obesity does not appear to increase LOS, readmission, or reoperation rates after lateral skull base tumor resection. The relationship between obesity and postoperative CSF leak, however, warrants further analysis.

Assessment of the impact of frailty on adverse surgical outcomes in patients undergoing surgery for intracranial tumors using modified frailty index: A systematic review and meta-analysis

BACKGROUND

Modified frailty index (MFI) is an emerging quantitative measure of frailty; however, the quantified risk of adverse outcomes in surgeries for intracranial tumors associated with increasing MFI scores has not been thoroughly reviewed in a comprehensive manner.

METHODS

MEDLINE (PubMed), Scopus, Web of Science, and Embase were searched to identify observational studies on the association between 5 and 11 item-modified frailty index (MFI) and perioperative outcomes for neurosurgical procedures including complications, mortality, readmission, and reoperation rate. Primary analysis pooled all comparisons with MFI scores greater than or equal to 1 versus non-frail participants using mixed-effects multilevel model for each outcome.

RESULTS

In total, 24 studies were included in the review and 19 studies with 114,707 surgical operations were included in the meta-analysis. While increasing MFI scores were associated with worse prognosis for all included outcomes, reoperation rate was only significantly higher in patients with MFI ≥ 3. Among surgical pathologies, glioblastoma was influenced by a greater extent to the impact of frailty on complications and mortality that most other etiologies. In agreement with qualitative evaluation of the included studies, meta-regression did not reveal association between mean age of the comparisons and complications rate.

CONCLUSION

The results of this meta-analysis provides quantitative risk assessment of adverse outcomes in neuro-oncological surgeries with increased frailty. The majority of literature suggests that MFI is a superior and independent predictor of adverse outcomes compared to age.

Frailty in Patients Undergoing Surgery for Brain Tumors: A Systematic Review of the Literature

BACKGROUND

Emerging literature suggests that frailty may be an important driver of postoperative outcomes in patients undergoing surgery for brain tumors. We systematically reviewed the literature on frailty in patients with brain tumor with respect to 3 questions: What methods of frailty assessment have been applied to patients with brain tumor? What thresholds have been defined to distinguish between different levels of frailty? What clinical outcomes does frailty predict in patients with brain tumor?

METHODS

A literature search was conducted using PubMed, Embase, The Cochrane Library, Web of Science, Scopus, and ClinicalTrials.gov. Included studies were specific to patients with brain tumor, used a validated instrument to assess frailty, and measured the impact of frailty on postoperative outcomes.

RESULTS

Of 753 citations, 21 studies met our inclusion criteria. Frailty instruments were studied, in order of frequency reported, including the 5-factor modified frailty index, 11-factor modified frailty index, Johns Hopkins Adjusted Clinical Groups frailty-defining diagnosis indicator, and Hopkins Frailty Score. Multiple different conventions and thresholds were reported for distinguishing the levels of frailty. Clinical outcomes associated with frailty included mortality, survival, complications, length of stay, charges, costs, discharge disposition, readmissions, and operative time.

CONCLUSIONS

Frailty is an increasingly popular concept in patients with brain tumor that is associated with important clinical outcomes. However, the extant literature is largely comprised of retrospective studies with heterogeneous definitions of frailty, thresholds for defining levels of frailty, and patient populations. Further work is needed to understand best practices in assessing frailty in patients with brain tumor and applying these concepts to clinical practice.

Estimating the causal effect of frailty index on vestibular disorders: A two-sample Mendelian randomization

Background

Frailty index and vestibular disorders appear to be associated in observational studies, but causality of the association remains unclear.

Methods

A two-sample Mendelian randomization (MR) study was implemented to explore the causal relationship between the frailty index and vestibular disorders in individuals of European descent. A genome-wide association study (GWAS) of frailty index was used as the exposure (n = 175, 226), whereas the GWAS of vestibular disorders was the outcome (n = 462,933). MR Steiger filtering method was conducted to investigate the causal effect of the frailty index on vestibular disorders. An inverse variance weighted (IVW) approach was used as the essential approach to examine the causality. Additionally, the MR-Egger methods, the simple mode analysis, the weighted median analysis, and the weighted mode analysis were used as supplementary methods. The MR-PRESSO analysis, the MR-Egger intercept analysis, and Cochran's Q statistical analysis also were used to detect the possible heterogeneity as well as directional pleiotropy. To evaluate this association, the odds ratio (OR) with 95% confidence intervals (CIs) was used. All statistical analyses were performed in R. The STROBE-MR checklist for the reporting of MR studies was used in this study.

Results

In total, 14 single nucleotide polymorphisms (SNPs) were identified as effective instrumental variables (IVs) in the two sample MR analyses. The significant causal effect of the frailty index on vestibular disorders was demonstrated by IVW method [OR 1.008 (95% CI 1.003, 1.013), p = 0.001]. Results from the various sensitivity analysis were consistent. The “leave-one-out” analysis indicated that our results were robust even without a single SNP. According to the MR-Egger intercept test [intercept = −0.000151, SE = 0.011, p = 0.544], genetic pleiotropy did not affect the results. No heterogeneity was detected by Cochran's Q test. Results of MR Steiger directionality test indicated the accuracy of our estimate of the potential causal direction (Steiger p < 0.001).

Conclusion

The MR study suggested that genetically predicted frailty index may be associated with an increased risk of vestibular disorders. Notably, considering the limitations of this study, the causal effects between frailty index and vestibular disorders need further investigation. These results support the importance of effectively managing frailty which may minimize vestibular disorders and improve the quality of life for those with vestibular disorders.

Clinical Staging to Estimate the Probability of Severe Postoperative Complications in Patients With Vestibular Schwannoma

Importance

Vestibular schwannomas have long been treated as a homogeneous entity. Clinical symptoms at presentation may help elucidate the underlaying pathophysiologic characteristics of tumor subtypes. Describing the heterogeneity of these benign tumors may assist in predicting clinical outcomes associated with their treatment.

Objective

To create a tumor staging system that incorporates symptoms at presentation and tumor size to predict severe surgical complications.

Design, Setting, and Participants

A retrospective cohort of patients at a single-center tertiary referral center from January 1, 1998, to October 13, 2020, was studied. Patients diagnosed with sporadic vestibular schwannoma surgically treated at Washington University in St Louis, Missouri, were included.

Main Outcomes and Measures

Severe surgical complications within 30 days of surgery as determined by the Clavien-Dindo classification system. Patients experiencing a complication of grade 3 or above were determined to have a severe complication.

Results

Of 185 patients evaluated, 40 (22%) had severe postoperative complications. Twenty of the 40 patients (50%) were women; mean (SD) age was 46 (13) years. Patients with severe complications were more likely to have large tumors (>2.5 cm in largest diameter), vestibular symptoms, and recent hearing loss at presentation. Using conjunctive consolidation, a 4-stage clinical severity staging system that incorporates clinical symptoms and tumor size at presentation was created to predict severe complications. The clinical severity staging system demonstrated an improvement in the ability to discriminate severe complications (C index, 0.754; 95% CI, 0.67-0.84) from a model of tumor size alone (C index, 0.706; 95% CI 0.62-0.79).

Conclusions and Relevance

This cohort study found that, among patients with vestibular schwannoma, symptoms present at initial evaluation, in addition to tumor size, served as predictors of severe postoperative complications. A new clinical severity staging system incorporating symptoms at presentation can be helpful for clinicians to identify patients at high risk for severe postoperative complications.

Associations of Baseline Frailty Status and Age With Outcomes in Patients Undergoing Vestibular Schwannoma Resection

Importance

Although numerous studies have evaluated the influence of advanced age on surgical outcomes following vestibular schwannoma (VS) resection, few if any large-scale investigations have assessed the comparative prognostic effects of age and frailty. As the population continues to age, it is imperative to further evaluate treatment and management strategies for older patients.

Objective

To conduct a population-based evaluation of the independent associations of chronological age and frailty (physiological age) with outcomes following VS resection.

Design, Setting, and Participants

In this large-scale, multicenter, cross-sectional analysis, weighted discharge data from the National Inpatient Sample were searched to identify adult patients (≥18 years old) who underwent VS resection from 2002 through 2017 using International Classification of Diseases, Ninth Revision, Clinical Modification and Tenth Revision, Clinical Modification codes. Data collection and analysis took place September to December 2020.

Main Outcomes and Measures

Complex samples regression models and receiver operating characteristic curve analysis were used to evaluate the independent associations of frailty and age (along with demographic confounders) with complications and discharge disposition. Frailty was evaluated using the previously validated 11-point modified frailty index (mFI).

Results

Among the 27 313 patients identified for VS resection, the mean (SEM) age was 50.4 (0.2) years, 15 031 (55.0%) were women, and 4720 (21.0%) were of non-White race/ethnicity, as determined by the National Inpatient Sample data source. Of the included patients, 15 090 (55.2%) were considered robust (mFI score = 0), 8204 (30.0%) were prefrail (mFI score = 1), 3022 (11.1%) were frail (mFI score = 2), and 996 (3.6%) were severely frail (mFI score ≥3). On univariable analysis, increasing frailty was associated with development of postoperative hemorrhagic or ischemic stroke (odds ratio [OR], 2.44 [95% CI, 2.07-2.87]; area under the curve, 0.73), while increasing age was not. Following multivariable analysis, increasing frailty and non-White race/ethnicity were independently associated with both mortality (adjusted OR [aOR], 2.32 [95% CI, 1.70-3.17], and aOR, 3.05 [95% CI, 1.02-9.12], respectively) and extended hospital stays (aOR, 1.54 [95% CI, 1.41-1.67], and aOR, 1.71 [95% CI, 1.42-2.05], respectively), while increasing age was not. Increasing frailty (aOR, 0.61 [95% CI, 0.56-0.67]), age (aOR, 0.98 [95% CI, 0.97-0.99]), and non-White race/ethnicity (aOR, 0.62 [95% CI 0.51-0.75]) were all independently associated with routine discharge.

Conclusions and Relevance

In this cross-sectional study, findings suggest that frailty may be more accurate for predicting outcomes and guiding treatment decisions than advanced patient age alone following VS resection.