Abstract 11: Temporal Changes in NIHSS Documentation and Stroke Severity among Patients Treated with Thrombolysis in the Massachusetts Coverdell Registry
Intro: IV tPA use has increased since the 2009 US guidelines recommended extending the window to 4.5 hr. The most common reasons for nontreatment are rapid improvement of stroke symptoms (RISS) and stroke “Too Mild”. We evaluated the NIHSS profile and outcomes over time in Massachusetts Coverdell patients receiving IV tPA, or not treated due to RISS and Too Mild.
Methods: All adults >18 yr arriving at a MA Coverdell hospital < 4.5 hr from time last known well with a diagnosis of ischemic stroke or TIA (with persistent symptoms) were included (n=10,433). We compared rates of NIHSS documentation, median NIHSS, and discharge home between 11/09-10/10 (Year 1, n=2,573) vs. 11/12-10/13 (Year 4, n=2,658) among All, IV tPA, RISS, and Too Mild patients. Ordinal variables were analyzed by Kruskal-Wallis and proportions by Chi square, and odds ratio of discharge home was adjusted for NIHSS, age, and gender. NIHSS was missing in 20% of cases.
Results: The two cohorts were similar by gender and vascular risk factors, except for age, HTN and dyslipidemia. IV tPA use within 4.5 hr of onset increased (19% vs. 25%, p<.0001) as did the documentation of an NIHSS among All patients (68% vs. 87%, p<.0001), IV tPA (86% vs. 97%, p<.0001), RISS (70% vs. 89%, p<.0001) and Too Mild (75% vs. 92%, p<.0001). Rates of RISS (27% vs. 26%) and Too Mild (19 vs. 22%) did not decrease but median NIHSS decreased over time among the IV tPA and Too Mild (Figure). Unadjusted rates of discharge home increased for IV tPA (25% vs. 31%, p=0.004), and for All (36% vs. 45%), RISS (51% vs. 63%), and Too Mild (52% vs. 67%; all comparisons, p<.0001). In multivariate analysis, discharge home increased among All (OR 1.9; 95%CI 1.6-2.2); RISS (2.2; 1.7-2.9) and Too Mild (2.4; 1.8-3.4) but not IV tPA (1.1, 0.8-1.6).
Discussion: IV tPA use in MA Coverdell patients is increasing and now reaches 25% of all early arriving subjects. NIHSS documentation is increasing as well, especially among subjects with lower NIHSS scores. The median NIHSS in RISS or Too Mild patients is reassuringly low, and decreased significantly among Too Mild patients. These data, coupled with the fact that unadjusted rates of discharge home among IV tPA patients are increasing while severity-adjusted rates are not, suggests that more patients previously felt to be Too Mild are now receiving IV tPA. Further efforts are still warranted.
Author Disclosures: L. Schwamm: B. Research Grant; Significant; NINDS and Genentech provide support for the multicenter MR Witness trial. G. Consultant/Advisory Board; Modest; Lundbeck, intl steering committee for DIAS3-4; Penumbra , DSMB on Penumbra 3D trial; CDC/MA DPH, stroke systems consultant. G. Parkinson: None. L. Coe: None.
- © 2014 by American Heart Association, Inc.