Autonomic dysfunction in first ever ischemic stroke: Prevalence, predictors and short term neurovascular outcome

Central autonomic dysfunction(AD) is reported post-stroke. Very few studies have looked at its impact on neurovascular outcome. We sought to study the prevalence and predictors of autonomic dysfunction in patients with first ever acute ischemic stroke and its impact on discharge and short term outcome.

Consecutive patients who presented between 2-4 weeks post stroke were prospectively recruited. Study period was April 2012-March 2014 (2 years). Subjects underwent clinical autonomic function testing using Ewing's battery at bedside and 24h Holter analysis for heart rate variability(HRV). HRV parameters studied included both time domain and frequency domain measures. Neurological and cardiovascular outcomes were assessed at discharge,3 months and 1year.

Of 101 patients of mean age 63yrs, 72% were men.Majority had moderate to severe strokes at onset (Mean NIHSS-13.9,MRS-3.1). Clinical bedside autonomic testing criteria were comparable to Holter detected dysautonomia in our study population (p value 0.3). Clinical autonomic dysfunction had a positive association with male gender whereas onset stroke severity and Insular involvement were associated with significantly higher incidence of autonomic dysfunction with both methodology. Those with autonomic dysfunction had more stroke severity at discharge, which was independent of onset severity. Increasing age, hemispheric laterality or presence of comorbidities had no impact on post-stroke dysautonomia.

Insular involvement and higher disability at onset are associated with greater incidence of autonomic dysfunction post-stroke. Those with AD had higher chance of infarct expansion and in hospital cardiovascular complications and poorer outcome at 1year, independent of onset stroke severity.