Determinants of mortality in stroke patients with right brain damage

Psychiatric sequelae of stroke affecting the non-dominant cerebral hemisphere

There are a plethora of cognitive sequelae in addition to neglect and extinction that arise with unilateral right hemispheric stroke (RHS). Cognitive deficits following non-dominant (right) hemisphere stroke are common with unilateral neglect and extinction being the most recognized examples. The severity of RHS is usually underestimated by the National Institutes of Health Stroke Scale (NIHSS), which in terms of lateralized right hemisphere cognitive deficits, tests only for visual inattention/extinction. They account for 2 out of 42 total possible points. Additional neuropsychiatric sequelae include but are not limited to deficiencies in affective prosody comprehension and production (aprosodias), understanding and expressing facial emotions, empathy, recognition of familiar faces, anxiety, mania, apathy, and psychosis. These sequelae have a profound impact on patients' quality of life; affecting communication, interpersonal relationships, and the ability to fulfill social roles. They also pose additional challenges to recovery. There is presently a gap in the literature regarding a cohesive overview of the significant cognitive sequelae following RHS. This paper serves as a narrative survey of the current understanding of the subject, with particular emphasis on neuropsychiatric poststroke syndromes not predominantly associated with left hemisphere lesions (LHL), bilateral lesions, hemiplegia, or paralysis. A more comprehensive understanding of the neuropsychological consequences of RHS extending beyond the typical associations of unilateral neglect and extinction may have important implications for clinical practice, including the ways in which clinicians approach diagnostics, treatment, and rehabilitation.

Neglecting the Difference

BACKGROUND AND PURPOSE

Patients with right hemispheric strokes (RHSs) present later to an emergency department, have a lower chance to receive intravenous recombinant tissue plasminogen activator (IV rt-PA), and have worse clinical outcomes than do patients with left hemispheric strokes (LHSs). We analyzed outcomes after IV rt-PA with respect to the side of the affected hemisphere.

METHODS

A prospective cohort of acute stroke patients was treated with IV rt-PA at the London Health Sciences Centre (December 1998 to March 2003). Differences between patients with RHS and LHS were identified by univariate analysis. Logistic-regression analysis was used to determine a subset of variables independently associated with major neurological improvement at 24 hours and good outcome at 3 months after treatment.

RESULTS

Of 219 stroke patients who received IV rt-PA, 165 had hemispheric strokes (68 RHSs and 97 LHSs). Patients with RHSs were less hypertensive (P=0.001) and had lower pretreatment National Institutes of Health Stroke Scale (NIHSS) scores (P=0.005). LHS (odds ratio [OR], 2.29; 95% CI, 1.14 to 4.59; P=0.019), age (OR, 0.96; 95% CI, 0.93 to 0.99; P=0.012), and pretreatment NIHSS (OR, 0.83; 95% CI, 0.78 to 0.89; P<0.0001) were independent predictors of 3-month outcome. Female sex (OR, 3; 95% CI, 1.53 to 5.90; P=0.001) and LHS (OR, 2.07; 95% CI, 1.05 to 4.08; P=0.03) were independent predictors of major neurological improvement at 24 hours after IV rt-PA.

CONCLUSIONS

Despite higher pretreatment NIHSS, patients with LHSs have a 2-fold increased chance of a good outcome 3 months after rt-PA treatment compared with patients with RHSs. This gain can be clinically detected at 24 hours after treatment. These results need to be coupled with neuroimaging and hemodynamic characteristics known to influence stroke outcome.