National Patterns and Outcomes of Neurologist Care in Acute Ischemic Stroke

Background &: Purpose Specialist care of acute ischemic stroke patients has been associated with improved outcomes but is not well-characterized. We sought to elucidate the involvement and influence of neurologists on acute ischemic stroke care. Methods:Using 100% Medicare datasets, index acute ischemic stroke admissions from 2016-2018 were identified with International Classification of Diseases, 10th Revision codes. Neurologists were identified by NPI code. Neurologist involvement in care was defined as: "neurologist involved in care"; "hospital with a neurologist"; and "percent of acute ischemic stroke treated by neurologist." Adjusted logistic regression models summarized exposure to neurologists and their association with outcomes (inpatient mortality, good outcome, and 30-day readmission). Results: Among 647838 index AIS admissions from 2016-2018, 15.6% included a neurologist involved in care, associated with receiving intravenous thrombolysis (19.1% vs 6.5%), endovascular thrombectomy (13.2% vs 1.4%), treatment at a teaching hospital (87.7% vs 55.5%), and treatment at a hospital in the highest volume quartile (95.3% vs 75.6%). Of 4797 hospitals, 36.1% had a neurologist, among which the mean percent of admissions treated by a neurologist was 14.7% (SD 24.4). Neurologist involvement was associated with increased inpatient mortality (OR 1.81; 95% CI 1.75-1.86), decreased odds of a good outcome (OR .92; 95% CI .90-.93), and increased 30-day readmission (OR 1.04; 95% C: 1.01-1.06). Conclusions: The minority of acute ischemic stroke admissions among the elderly in the US are treated by neurologists. Neurologist involvement in care is associated with worse outcomes, possibly from the allocation of severe cases to neurologists.