Is {mRankin} scale correlated with {mTICI}? A systematic review and meta-regression on {RCTs} and registries

Purpose This study aimed to evaluate the numeric correlation between modified treatment in cerebral infarction (mTICI)≥2b/3 and modified Rankin Scale (mRS)≤2 in RCT and registries. Material and Methods Literature search was performed on PubMed/OVID for studies in 2015–2021, mTICI, mRS, and sample size were recorded. Exclusion criteria were monocentric, non-human, and non-English studies. Studies qualities were assessed with MINORS/RoB2. A meta-analysis with a random-effects model was performed. Meta-logistic and meta-linear regressions were used to correlate mTICI and mRS in both RCTs and registries. The Z-test was used to compare the coefficients between RCTs/registries. Results We evaluated thirty-four studies (17 registries; 17 RCTs) for 29540 patients (27031 from registries (median registry 1192.0 [CI95 % 698.7–1992.8]; 2509 from RCTs [median RCT 165.0 [CI95 % 98.1–234.0]). 10/17(58.8 %) registries considered also vertebrobasilar system strokes. Overall mRs≤2 was 46.0 (CI95 % 43.8–48.3) with I2 = 92.6 %. The odd-ratio of obtaining a mRS≤2 for a singular increased of mTICI≥2b rate was: 1.49(CI95 % 1.22–2.01) for all studies (for 1 % increase of mTICI≥2b the odds for obtaining mRS≤2 was 1.49), 1.50(CI95 % 1.00–2.23) for RCTs and 1.50(CI95 % 1.10–2.23) for registries. mTICI≥2b and mRS had a positive correlation with coefficient of 0.49(CI95 % 0.22–0.75, p = 0.001) for all studies (for 1 % increase of mTICI≥2b the mRS≤2 rate augment by 0.49 %), 0.51(CI95 % 0.10–0.91) for RCTs and 0.46(CI 95 % 0.09–0.84) for registries. No differences were found in coefficients between RCTs/registries (p = 0.50; p = 0.57; respectively). Conclusions Unitary increased of mTICI≥2b rate correspond to an augment of mRS≤2 by 0.49(CI95 % 0.22–0.75) with odd-ratio of obtaining mRS≤2 of 1.49(CI95 % 1.22–2.01), without significantly differences in coefficients.