Effect of frailty on outcomes of endovascular treatment for acute ischaemic stroke in older patients

Role of frailty in predicting outcomes after stroke: a systematic review and meta-analysis

Background

Stroke is considered the second most common cause of death and the third leading cause of disability worldwide. Frailty, characterized by increased vulnerability to stressors, is emerging as a key factor affecting outcomes in older adults and stroke patients. This study aimed to estimate the prevalence of frailty in acute stroke patients and assess its association with mortality and poor functional outcome.

Methods

Medline, Google Scholar, and Science Direct databases were systematically searched for English-language studies that included adult stroke patients (>16 years), have defined frailty, and reported mortality and functional outcomes. Meta-analysis was done using STATA 14.2, and the results were expressed as pooled odds ratios (OR) with 95% confidence intervals (CI). Heterogeneity was assessed using the I2 statistic and the Chi-square test. Study quality was evaluated using the Newcastle Ottawa Scale (NOS).

Results

Twenty-five studies were included in the analysis. Frailty prevalence in stroke patients was 23% (95% CI 22% - 23%). Unadjusted analysis showed an OR of 2.66 (95% CI: 1.93 - 3.67) for mortality and 2.04 (95% CI: 1.49 - 2.80) for poor functional outcome. Adjusted estimates indicated an OR of 1.22 (95% CI: 1.1 - 1.35) for mortality and 1.21 (95% CI: 1.04 - 1.41) for poor functional outcome, with substantial heterogeneity for both adjusted and unadjusted analyses. No publication bias was detected for the prevalence of frailty. However, there was a publication bias for the association between frailty and mortality.

Conclusions

Frailty was significantly associated with increased mortality and poorer functional outcomes in stroke patients. Our study highlights the need to focus on frailty in stroke patients to improve outcomes and quality of life. Further research should aim to standardize assessment of frailty and reduce heterogeneity in study outcomes.

Systematic review registration

https://www.crd.york.ac.uk/prospero/#searchadvanced, CRD42023470325.

Prevalence and outcome of pre-onset frailty in patients with acute stroke

BACKGROUND

Frailty in older individuals is an underappreciated condition that affects the incidence and/or prognosis of stroke.

OBJECTIVES

We evaluated the prevalence of pre-onset frailty in patients with acute first-onset and recurrent strokes and association between pre-onset frailty and functional disability at hospital discharge.

METHODS

This prospective cohort study included 210 acute stroke patients admitted to the Stroke Unit of Nippon Medical School Hospital during November 2021-June 2022. The mean participant age was 79.2 ± 7.4 years. Age, sex, pre-onset frailty, body mass index (BMI), stroke type, medical history, and National Institutes of Health Stroke Scale (NIHSS) score at admission were evaluated. Frailty was defined as a clinical frailty scale (CFS) score ≥ 5. Frailty prevalence was calculated for all patients, and scores of functional disabilities at discharge were evaluated using modified Rankin scale.

RESULTS

Overall frailty prevalence was 31% in all stroke patients, with 24% and 47% of first-onset and recurrent strokes, respectively. Pre-onset frailty, NIHSS score at admission, age, stroke type, previous stroke, sex, BMI, dyslipidemia, and atrial fibrillation were significantly associated with functional disability at discharge. Logistic regression analysis revealed that CFS score, NIHSS score at admission, and previous stroke were independent predictors of functional disability at discharge.

CONCLUSIONS

Approximately one-fourth of patients with first-onset stroke had pre-onset frailty; the rate doubled in recurrent stroke; these rates appear to be much larger than rate in healthy individuals. Pre-onset frailty, a negative independent factor affecting functional disability at discharge, is important for pre-onset frailty evaluation and rehabilitation intervention in acute stroke patients.

To what extent does frailty mediate the association between age and the outcomes of brain reperfusion following acute ischemic stroke?

Objective

We evaluated the extent to which frailty mediated the association between age, poor functional outcomes, and mortality after acute ischemic stroke when patients were treated with brain reperfusion (thrombolytic therapy and/or thrombectomy).

Materials and methods

This retrospective cohort study included patients diagnosed with ischemic stroke who had undergone intravenous cerebral reperfusion therapy and/or mechanical thrombectomy. We created a mediation model by analyzing the direct natural effect of an mRS score > 2 and death on age-mediated frailty according to the Frailty Index.

Results

We enrolled 292 patients with acute ischemic stroke who underwent brain reperfusion. Their mean age was 67.7 ± 13.1 years. Ninety days after the stroke ictus, 54 (18.5%) participants died, and 83 (28.4%) lived with moderate to severe disability (2 < mRS < 6). In the mediation analysis of the composite outcome of disability (mRS score > 2) or death, frailty accounted for 28% of the total effect of age. The models used to test for the interaction between age and frailty did not show statistically significant interactions for either outcome, and the addition of the interaction did not significantly change the direct or indirect effects, nor did it improve model fit.

Conclusion

Frailty mediated almost one-third of the effect of age on the composite outcome of disability or death after acute ischemic stroke.

Is endovascular treatment still good for acute ischemic stroke in the elderly? A meta-analysis of observational studies in the last decade

Background

The lack of randomized evidence makes it difficult to establish reliable treatment recommendations for endovascular treatment (EVT) in elderly patients. This meta-analysis aims to evaluate the therapeutic effects of endovascular treatment for acute ischemic stroke in the elderly compared with younger patients.

Methods

Comprehensive literature retrieval was conducted to identify studies that directly compared the outcomes of EVT in elderly patients and those aged <80 years. The primary outcome was functional independence, defined as mRS 0-2 at 90 days after EVT. The secondary outcomes were the rate of successful recanalization, symptomatic intracranial hemorrhage (sICH) and mortality. Odds ratios (ORs) were estimated using a random effects model.

Results

In total, twenty-six studies with 9,492 enrolled participants were identified. Our results showed that, compared with patients aged <80 years undergoing EVT, EVT was associated with a lower rate of functional independence at 90 days (OR = 0.38; 95% CI, 0.33-0.45; p < 0.00001) and a higher mortality rate (OR = 2.51; 95% CI, 1.98-3.18; p < 0.00001) in the elderly. Furthermore, even without a significantly observed increase in sICH (OR = 1.19; 95% CI, 0.96-1.47; p = 0.11), EVT appeared to be associated with a lower rate of successful recanalization (OR = 0.81; 95% CI, 0.68-0.96; p = 0.02).

Conclusion

Evidence from observational studies revealed that EVT has less functional outcomes in elderly patients with acute ischemic stroke. Further studies are needed to better identify patients aged ≥80 years who could potentially benefit from EVT.

Genetic liability to frailty in relation to functional outcome after ischemic stroke

BACKGROUND

Frailty appears to be associated with unfavorable prognosis after stroke in observational studies, but the causality remains largely unknown.

AIMS

The aim of this study is to investigate the potential causal effect of frailty on functional outcome at 3 months after ischemic stroke using the Mendelian randomization (MR) framework.

METHODS

Genetic instruments for frailty index were identified in a genome-wide association study meta-analysis including 175,226 individuals of European descent. Corresponding genetic association estimates for functional outcome after ischemic stroke at 90 days were taken from the Genetic of Ischemic Stroke Functional Outcome (GISCOME) network of 6021 patients. We performed inverse-variance weighted MR as the main analyses, followed by several alternate methods and sensitivity analyses.

RESULTS

In univariable MR, we found evidence that genetically predicted higher frailty index (odds ratio (OR) = 5.12; 95% confidence interval (CI) = 1.31-20.09; p = 0.019) was associated with worse functional outcome (modified Rankin Scale score ⩾3) after ischemic stroke. In further multivariable MR adjusting for potential confounding traits including body mass index, C-reactive protein, inflammatory bowel disease, and smoking initiation, the overall patterns between genetic liability to frailty and poor functional outcome status remained. Sensitivity analyses with complementary methods and with model unadjusted for baseline stroke severity (OR = 4.19; 95% CI = 1.26-13.90; p = 0.019) yielded broadly concordant results.

CONCLUSIONS

The present MR study suggested a possible causal effect of frailty on poor functional outcome after ischemic stroke. Frailty might represent a potential target for intervention to improve recovery after ischemic stroke.

Effect of admission in the stroke care unit versus intensive care unit on in-hospital mortality in patients with acute ischemic stroke

BACKGROUND/OBJECTIVE

Few reports have directly compared the outcomes of patients with acute ischemic stroke (AIS) who are managed in a stroke care unit (SCU) with those who are managed in an intensive care units (ICU). This large database study in Japan aimed to compare in-hospital mortality between patients with AIS admitted into SCU and those admitted into ICU.

METHODS

Patients with AIS who were admitted between April 1, 2014, and March 31, 2019, were selected from the administrative database and divided into the SCU and ICU groups. We calculated the propensity score to match groups for which the admission unit assignment was independent of confounding factors, including the modified Rankin scale (mRS) score. The primary outcome was in-hospital mortality, and secondary outcomes were the mRS score at discharge, length of stay (LOS), and total hospitalization cost.

RESULTS

Overall, 8,683 patients were included, and 960 pairs were matched. After matching, the in-hospital mortality rates of the SCU and ICU groups were not significantly different (5.9% vs. 7.9%, P = 0.106). LOS was significantly shorter (SCU = 20.9 vs. ICU = 26.2 days, P < 0.001) and expenses were significantly lower in the SCU group than in the ICU group (SCU = 1,686,588 vs. ICU = 1,998,260 yen, P < 0.001). mRS scores (score of 1-3 or 4-6) at discharge were not significantly different after matching. Stratified analysis showed that the in-hospital mortality rate was lower in the ICU group than in the SCU group among patients who underwent thrombectomy.

CONCLUSIONS

In-hospital mortality was not significantly different between the ICU and SCU groups, with significantly lower costs and shorter LOS in the SCU group than in the ICU group.

Mobile health-technology integrated care in secondary prevention atrial fibrillation patients: a post-hoc analysis from the mAFA-II randomized clinical trial

AF patients with history of thromboembolic events are at higher risk of thromboembolic recurrences, despite appropriate antithrombotic treatment. We aimed to evaluate the effect of mobile health (mHealth) technology-implemented 'Atrial fibrillation Better Care' (ABC) pathway approach (mAFA intervention) in secondary prevention AF patients. The Mobile Health Technology for Improved Screening and Optimized Integrated Care in AF (mAFA-II) cluster randomized trial enrolled adult AF patients across 40 centers in China. The main outcome was the composite outcome of stroke or thromboembolism, all-cause death, and rehospitalization. Using Inverse Probability of Treatment Weighting (IPTW), we evaluated the effect of the mAFA intervention in patients with and without prior history of thromboembolic events (i.e., ischemic stroke or thromboembolism). Among the 3324 patients enrolled in the trial, 496 (14.9%, mean age: 75.1 ± 11.4 years, 35.9% females) had a previous episode of thromboembolic event. No significant interaction was observed for the effect of mAFA intervention in patients with vs. without history of thromboembolic events [Hazard ratio, (HR): 0.38, 95% confidence interval (CI):0.18-0.80 vs. HR 0.55, 95% CI 0.17-1.76, p for interaction = 0.587); however, a trend towards lower efficacy of mAFA intervention among AF patients in secondary prevention was observed for secondary outcomes, with significant interaction for bleeding events (p = 0.034) and the composite of cardiovascular events (p = 0.015). A mHealth-technology-implemented ABC pathway provided generally consistent reduction of the risk of primary outcome in both primary and secondary prevention AF patients. Secondary prevention patients may require further specific approaches to improve clinical outcomes such as bleeding and cardiovascular events.Trial registration: WHO International Clinical Trials Registry Platform (ICTRP) Registration number ChiCTR-OOC-17014138.

Implications of frailty in acute ischemic stroke receiving endovascular treatment: systematic review and meta-analysis

BACKGROUND

Frailty is a state of cumulative degeneration of bodily functions that is consistently associated with poor outcomes in older people following illness. Combined stroke intervention and frailty may yield additive and synergistic effects adults with stroke.

OBJECTIVE

To evaluate the safety and efficacy of endovascular therapy (EVT) in frail patients.

METHODS

We conducted a systematic review of the relationship between debilitation and acute ischemic stroke (AIS) after EVT. Until August 2022, researchers have searched three databases (Pubmed, EMBASE and Cochrane). Random-effects meta-analysis, combined ratio (OR) and 95% confidence interval (95%CI) were used to assess efficacy values. The I² statistic was used to assess heterogeneity. Comprehensive meta-analysis software was used for meta-analysis.

RESULTS

We ultimately included eight studies including 3662 non-overlapping participants. Four studies used the Clinical Frailty Scale (CFS), two studies used the Hospital Frailty Risk Score (HFRS), a study used frailty index and a study used the comprehensive geriatric assessment (CGA). Frailty prevalence: 35%; 95% CI, 0.27-0.43; low quality evidence, downgraded due to heterogeneity, bias. Random effects showed that poor functional outcome (5 studies, OR 1.956, 95% CI 1.256-3.048) and mortality (9 studies, OR 2.320, 95% CI 1.680-3.205) was significantly associated with frailty. In adjusted analyses, poor functional outcome (4 studies, OR_adj 1.189, 95% CI 1.043-1.357), and mortality (3 studies, OR_adj 1.036, 95% CI 1.008-1.065) were significantly associated with frailty.

CONCLUSION

Pre-stroke frailty is an important predictor of poor prognosis assessed by EVT and can be added to the classical predictors of stroke outcome. Routine assessment of pre-stroke frailty can help patients to make decisions about the efficacy of their choice of EVT.

Effect of Comorbidity Burden and Polypharmacy on Poor Functional Outcome in Acute Ischemic Stroke

PURPOSE

Comorbidities and polypharmacy are risk factors for worse outcome in stroke. However, comorbidities and polypharmacy are mostly studied separately with various approaches to assess them. We aimed to analyze the impact of comorbidity burden and polypharmacy on functional outcome in acute ischemic stroke (AIS) patients undergoing mechanical thrombectomy (MT).

METHODS

Acute ischemic stroke patients with large vessel occlusion (LVO) treated with MT from a prospective observational study were analyzed. Relevant comorbidity burden was defined as a Charlson Comorbidity Index (CCI) score ≥ 2, polypharmacy as the intake of ≥ 5 medications at time of stroke onset. Favorable outcome was a score of 0-2 on the modified Rankin scale at 90 days after stroke. The effect of comorbidity burden and polypharmacy on favorable outcome was studied via multivariable regression analysis.

RESULTS

Of 903 patients enrolled, 703 AIS patients (mean age 73.4 years, 54.9% female) with anterior circulation LVO were included. A CCI ≥ 2 was present in 226 (32.1%) patients, polypharmacy in 315 (44.8%) patients. Favorable outcome was less frequently achieved in patients with a CCI ≥ 2 (47, 20.8% vs. 172, 36.1%, p < 0.001), and in patients with polypharmacy (69, 21.9% vs. 150, 38.7%, p < 0.001). In multivariable regression analysis including clinical covariates, a CCI ≥ 2 was associated with lower odds of favorable outcome (odds ratio, OR 0.52, 95% confidence interval, 95% CI 0.33-0.82, p = 0.005), while polypharmacy was not (OR 0.81, 95% CI 0.52-1.27, p = 0.362).

CONCLUSION

Relevant comorbidity burden and polypharmacy are common in AIS patients with LVO, with comorbidity burden being a risk factor for poor outcome.

Endovascular thrombectomy for acute ischaemic stroke improves and maintains function in the very elderly: A multicentre propensity score matched analysis

Introduction:

The very elderly (⩾80 years) are under-represented in randomised endovascular thrombectomy (EVT) clinical trials for acute ischaemic stroke. Rates of independent outcome in this group are generally lower than the less-old patients but the comparisons may be biased by an imbalance of non-age related baseline characteristics, treatment related metrics and medical risk factors.

Patients and methods:

We compared outcomes between very elderly (⩾80) and the less-old (<80 years) using retrospective data from consecutive patients receiving EVT from four comprehensive stroke centres in New Zealand and Australia. We used propensity score matching or multivariable logistic regression to account for confounders.

Results:

We included 600 patients (300 in each age cohort) after propensity score matching from an initial group of 1270 patients. The median baseline National Institutes of Health Stroke Scale was 16 (11–21), with 455 (75.8%) having symptom free pre-stroke independent function, and 268 (44.7%) receiving intravenous thrombolysis. Good functional outcome (90-day modified Rankin Scale 0–2) was achieved in 282 (46.8%), with very elderly patients having less proportion of good outcome compared to the less-old (118 (39.3%) vs 163 (54.3%), p < 0.01). There was no difference between the very elderly and the less-old in the proportion of patients who returned to baseline function at 90 days (56 (18.7%) vs 62 (20.7%), p = 0.54). All-cause 90-day mortality was higher in the very elderly (75 (25%) vs 49 (16.3%), p < 0.01), without a difference in symptomatic haemorrhage (very elderly 11 (3.7%) vs 6 (2.0%), p = 0.33). In the multivariable logistic regression models, the very elderly were significantly associated with reduced odds of good 90-day outcome (OR 0.49, 95% CI 0.34–0.69, p < 0.01) but not with return to baseline function (OR 0.85, 90% CI 0.54–1.29, p = 0.45) after adjusting for confounders.

Conclusion:

Endovascular thrombectomy can be successfully and safely performed in the very elderly. Despite an increase in all-cause 90-day mortality, selected very elderly patients are as likely as younger patients with similar baseline characteristics to return to baseline function following EVT.