Death and ADL Dependency After Scoring Zero on the NIHSS: A Swedish Retrospective Registry-Based Study.

BACKGROUND AND OBJECTIVES

Of all strokes, mild strokes (defined as 5 points or less on the National Institutes of Health Stroke Scale [NIHSS]) are in the majority. However, up to one-third of patients with mild strokes still exhibit significant deficits 3 months after the stroke. Studies on the presumably mildest strokes, defined by zero points on the NIHSS (0-NIHSS) at admission, are scarce. Hence, we aimed to study patient characteristics and outcomes among patients with 0-NIHSS strokes.

METHODS

Our retrospective registry-based study included a total of 6,491 adult patients with stroke admitted to 3 different stroke units in Gothenburg, Sweden, from November 2014 to June 2019. Our main outcome was a composite measure including death and activities of daily living (ADL) dependency 3 months after the stroke. Analyses of patient characteristics were followed by adjusted analyses including multiple confounders.

RESULTS

In total, 5,945 patients had data on NIHSS at admission, of whom 1,412 (24%) presented with a 0-NIHSS stroke. Among these, the median age was 72 years, 600 (42%) were female, and 86 (6%) had a hemorrhagic stroke. Among previously ADL-independent patients, 65 (6%) were either dead or ADL-dependent 3 months after the stroke. Prestroke physical inactivity (OR 2.48, 95% CI 1.40-4.38) and age (OR 1.05 per gained year, 95% CI 1.02-1.08) significantly increased the risk of death and ADL dependency.

DISCUSSION

One of 17 patients has either died or become ADL-dependent 3 months after a 0-NIHSS stroke, stressing that these strokes are not always benign. Older and physically inactive patients are at greater risk of an adverse outcome.