Difference of very-longterm-outcome according to domicile, distance from EVT-hospital and transfer to tertial center.

Master-Thesis:
1) Difference between Very long term follow up of bridging-therapy vs. EVT alone.
2) Comparison medication by getting out of the hospital and now.
3) Very long-term FU according to occlusion-sites.
4) Difference in outcomes in patients treated with EVT/IVT vs. EVT alone

Effect of neurehabilitation on longterm FU after EVT

• Life Expectancy after Stroke Based On Age, Sex, and Rankin Grade of Disability: A Synthesis Shavelle et al.: For example, a patient now at mRS4 who was previously at mRS2 may have a different prognosis from one in mRS4
  continuously since the time of stroke. We are not, however, aware of any empirical evidence on this topic. In addition, it may be worthwhile to determine whether rehabilitation efforts were insufficient; for example, a patient narrowly at mRS grade 3 (rather than grade 4) only due to intensive rehabilitation may have a worse prognosis than one in the same grade who did not recover as well as they otherwise would have under more ideal circumstances. The results given it this study can be practically used by epidemiologists and medical researchers for benchmarking. Specifically, the empirical survival results in any (future) study may be evaluated in light of those given in this study. This could take the simple form of comparing the observed and expected survival curves or instead by comparing the observed and expected number of deaths in both cases after controlling for important patient differences in age, sex, and severity of disability. One could then determine if survival in the new study group was better, worse, or similar to these baseline values.
  
  

furthers investigations:

• Certainly difficult because high mRS do rehab and low NIHSS not. -> Stratification by mRS and by age.
• Comparison mRS posthosp, postreha and now -> decrease of mRS post-reha? Reincreased in very-longterm-FU vs. stay stable after reha ?

„Long‐term outcome changes after mechanical thrombectomy for anterior circulation acute ischemic stroke“, Fuhrer et al.,Journal of Neurology, 2019

• Method:
  -> All patients were patients with EVT and longterm mRS were included.
  -> The following demographic and clinical data were gathered: National Institutes of Health Stroke Scale (NIHSS) score on admission and at discharge, presence of co-morbidities (prior stroke, atrial fibrillation, cardiovascular risk factors), and infarction etiology [TOAST].
  -> Short- and Longterm outcomes assessment via structured telephone interview with the interviewer blinded for data obtained during the hospital stay.
  -> Primary endpoint was the long-term functional outcome (mRS at 12 months) including the longitudinal changes between short- and long-term outcomes reflected by mRS levels at 3 and 12 months after stroke. Secondary outcomes included a dichotomized outcome analysis of favorable out- come (mRS 0–2) versus unfavorable (mRS 3–6), and mortality after 1 year.
  
  • Statistics: Descriptive data [median and interquartile ranges (IQR) for continuous variables and frequency distributions for binary or categorical variables]. This analysis was done using a linear model calculating the coefficient reflecting the difference between mRS measurements (short versus long term, ΔmRS) and the time period (in 28 day-steps) after MT as the independent variable.
    -> Adjustments were made by excluding patients who deceased (mRS 6) between acute MT treatment and the 3-month interview as they would not be able to show changes until the follow-up. Further, data were adjusted according to the date and the results of the short-term mRS assessment.
    -> A univariate analysis for potential co-factors in the linear model of long-term outcome was performed from a prespecified list of clinical and imaging factors (Table 2). Variable selection for inclusion into a multi-variable analysis was done via backward elimination using p < 0.157 as threshold, according to the Akaike information criterion.
    -> Logistic regression analyses of dichotomized mRS outcome levels (favorable mRS 0–2) and mortality, respectively. Selection of variables for logistic regression analysis was again done via Akaike from a pre-specified list as described for the linear model.
• Results:
  -> Long-term mRS follow-up was obtained in all 264 patients after a median of 434 days (IQR 378–689 days).
  -> 230 also with short-term FU
  -> Of these patients, 171 were alive at the time of short-term follow-up (mRS level of < 6 points) and were included in the linear model assessing long-term outcome change.
  -> Between short-term and long-term follow-up, 27.5% (47 of 171) patients showed changes in their mRS levels. 76.6% (36 of 47) of these patients experienced an improvement in mRS levels.
  -> Analysis of in-ward rehabilitation.
  -> A decline in mRS levels was noted in 23.4% (11 of 47) patients.
  -> After variable selection, a multivariable analysis of the linear model showed that higher NIHSS at discharge and right hemispheric stroke were independent predictors of longitudinal worsening of long-term outcome.
  -> Favorable outcome was observed in 37.8% (87 of 230) at short term and in 41.3% (95 of 230) at long term.
  -> Between short- and long-term follow-up, mRS outcomes improved from unfavorable to a favorable outcome in 5.7% (13 of 230) patients, whereas worsening was noted from favorable to an unfavorable outcome in 2.2% (5 of 230) patients.
  ->

„Second part“

• Mortality
  Overall, 25.4% (68 of 264) patients died during the entire follow-up period from hospital admission until the long-term interview. The majority of deaths occurred during hospital stay: 39 patients (57.4% of all deaths) died after a median of 4 days, IQR 3–8) within the primary hospitalization for MT treatment. 20 patients (29.4% of deaths) deceased within the first 90 days after hospital discharge (after a median of 15 days, IQR 12–29.5). Another six patients were found dead at short-term follow-up but the exact date and cause of death could not be obtained. Only nine patients (13.2% of deaths) deceased between the short- and long-term follow-up (after a median of 217 days, IQR 146–504; Fig. 4).
• Discussion: The length of rehabilitation may affect long-term outcome changes.
  Given long-term follow-up is often compromised by dropouts, we aimed for low drop out rates but no data could be obtained after 1 year in 11.4% patients. However, their baseline data did not differ significantly to the remaining cohort studied.

Variable-comparison -> use of statistical test.

• mRS: Evolution LTFU vs. VLTFU
  -> H0 -> improvement of mRS across time.
  -> mRS LTFU vs. mRS VLTFU.
  -> Descriptive statistics, Paired Samples t-Tests ?
  
  

-> Descriptive statistics

• Within vs beyond guidelines
  -> H0 -> worse outcomes for patients treated beyond guidelines.
  -> Independant variante: indications within vs. beyond guidelines.
  -> Dependant variante: mRS-outcome.
  -> Test the equivalence between two samples: Equivalence test (TOST)
  or
  -> Compare two observed means (independent samples): t-test on two independent samples or Mann-Whitney's test

Assessment of quality of life

• QoL -> scores and place of residence.
• Only use of descriptive statistics ? Or possibility to compare with Beyond ? No control group ...

Exclusion of short-term mortality ? At 3-months FU ?

• As done in „Life Expectancy after Stroke Based On Age, Sex, and Rankin Grade of Disability: A Synthesis“ –> rather a study limitation according to paper.
• Also done in „Long‐term outcome changes after mechanical thrombectomy for anterior circulation acute ischemic stroke“ Fuhrer et al.: Adjustments were made by excluding patients who deceased (mRS 6) between acute MT treatment and the 3-month interview as they would not be able to show changes until the follow-up

That there are significant differences in life expectancies between the grades demonstrates the importance of rehabilitation

Calcule of relative risk as well as the hazard ratio
–> finally quite the same

Impact of ENI — early neurological improvement (24H NIHSS) of VLTFU

Further research is required to determine if functional Outcome (mRS at 3-month) is a prognostic factor for long-term mortality.

Mortality and ASPECT: measurement of semi-quantitative (ASPECTS) and quantitative (core volume) imaging modalities.