Introduction: Studies examining cognitive outcomes for pediatric stroke are sparse, and few account for stroke severity. The Pediatric Stroke Outcome Measure (PSOM) provides an objective, comprehensive rating of neurological impairment. This study investigated the relationship between initial PSOM score and long-term cognitive outcomes. It was hypothesized that greater severity of stroke (worse initial PSOM score) would predict lower IQ at long-term follow-up. Other factors considered were age at stroke and months post stroke. Age-related studies in broad cognitive outcomes for pediatric stroke are sparse and somewhat inconsistent in findings. It was hypothesized that severity of stroke would be more relevant than age of stroke for long-term cognitive outcomes.
Methods: PSOM scores at initial visit and IQ scores at long-term follow-up (M=3.77 years) were obtained for 84 survivors of pediatric stroke ages 4:0-25:6 (M=11:5 years; 37 females). A one-sample t-test was conducted to compare mean IQ to the normative sample. To examine the hypotheses, all variables of interest (PSOM, age at stroke, and months s/p) were entered into a stepwise regression equation.
Results: Mean IQ for the sample was 84.77 (SD=17.26), significantly below average relative to healthy norms (t=-8.088, p=.000). PSOM scores ranged 0-5.5 (median/mode=1.0). The regression was significant (F=8.798; p=.000), with both PSOM score (b=-.350; t=-3.483; p=.001) and months post stroke (b=-.355; t=-3.005; p=.004) significantly contributing to the model, but not age at stroke.
Conclusions: PSOM was more relevant than age at stroke in predicting long-term cognitive outcomes, and greater stroke severity was associated with lower IQ at follow-up. Finding suggest that initial PSOM score and greater time since stroke may be more relevant to long-term cognitive outcomes than age at stroke. The present study lends validity to using the PSOM both as a marker of functional severity of stroke and a potential indicator of relative risk for poorer long-term cognitive outcomes. Better predictors of cognitive outcomes for pediatric stroke are greatly needed in order to facilitate earlier intervention/rehabilitation and improve the efficacy of such efforts.