Abstract 2962: Recovery from Post-Stroke Visual Impairment: Evidence from a Clinical Trials Resource

Abstract

Introduction: Visual impairment after stroke may impact overall disability, but the natural history of recovery from visual impairment (VI) after stroke is poorly characterized. We examined recovery from eye movement disorders and visual field defects after stroke. Methods: We extracted anonymised data on age, medical history, modified Rankin Score (mRS), National Institutes of Health Stroke Scale (NIHSS) and European Quality of Life Score (EQ-5D) from the Virtual International Stroke Trials Archive (VISTA). We described eye movement disorders and visual field defects using the Best Gaze and Visual domains of the NIHSS and related these to recovery at 90 days. As visual neglect was not available in our dataset, we used the Extinction domain on the NIHSS to provide a broad measure of neglect of personal, visual, tactile, auditory or spatial stimulation. We used Proportional Odds Modelling, adjusting for age, medical history, vision-unrelated NIHSS domain scores [total baseline NIHSS score - (Best Gaze + Visual Scores)], rt-PA administration and type of stroke to examine associations among VI at baseline, functional outcome (mRS) and quality of life (EQ-5D) at 90 days. Results: Eye movement disorders or visual field defects were reported in 7,123/11,623 (61.3%) patients at baseline. By 90 days, these impairments had resolved in 3,177/7,123 (44.6%) patients but persisted in 2,074/7,123 (29.1%); 1,622/7,123 (22.8%) patients had died and 250/7,123 (3.5%) patients were lost to follow up. The total burden of persistent VI at 90 days in all stroke survivors was 2,074/9,384 (22.1%). Complete homonymous hemianopia was most prevalent at both baseline (n=4,165; 35.9%) and at 90 days (n=1,071; 11.5%). Partial gaze palsy (p<0.0001, OR=0.15, 95% CI [0.13, 0.17]), forced deviation (p<0.0001, OR=0.48, 95% CI [0.44, 0.54]) and complete homonymous hemianopia (p<0.0001, OR=0.67, 95% CI [0.61, 0.72]) at baseline were associated with poor functional outcome by mRS at 90 days. Partial gaze palsy and forced deviation at baseline were associated with poorer scores on all domains of EQ-5D except Anxiety/Depression. Thrombolysis was associated with recovery from VI at 90 days (p<0.0001 OR =2.32, 95% CI [2.02, 2.67]). Conclusions: VI is arguably a major stroke-related impairment with 22% of all stroke survivors exhibiting persistent visual impairment at 90 days. The extent to which VI causes poor outcome or is simply associated with severe stroke merits further investigation. The consequences of a co-existing VI should be considered in stroke multidisciplinary rehabilitation assessments and interventions.