Too risky, too large, too late, or too mild—Reasons for not treating ischemic stroke patients and the related outcomes

Background Despite effective treatments, many patients are still not offered reperfusion therapy for acute ischemic stroke. Methods We present a single-center observational study on acute ischemic stroke patients, who presented as candidates for reperfusion therapy but were deemed ineligible after work-up. Reasons for non-treatment were obtained by studying patient files and subsequently grouped into “too risky” (e.g., anticoagulant use, comorbidities), “too large” (large infarct), “too late” (late presentation of stroke and wake-up strokes), or “too mild” (clinically mild/remitting symptoms). Modified Rankin scale (mRS) score was prospectively collected in all patients by a structured telephone interview. All non-treated patients with a National Institute of Health Stroke Scale (NIHSS) score of 0–5 were compared with a similar cohort that was treated. Results Of 529 patients with acute ischemic stroke arriving as reperfusion therapy candidates, 198 (37.4%) were not treated. The majority (42%) were not treated due to admission outside the treatment window (too late) and 24% had absolute contraindications (too risky). Only 8% was excluded because their infarct was too large [median Alberta Stroke Program Early CT score 3 (2–4)]. In the “too mild” group (14%) the percentage of patients not being independent at 90 days was 30%. The adjusted odds ratio for a better outcome (lower mRS) among treated patients with NIHSS 0–5 compared with non-treated was 1.93 (95% confidence interval 1.15–3.23). Conclusion Presenting outside the treatment window is still the most common reason for not receiving therapy. Our study suggests a benefit of thrombolysis for patients with mild symptoms.