Global and domain-specific cognitive impairment and outcome after subarachnoid hemorrhage

Abstract

BACKGROUND: Cognitive dysfunction is the most common form of neurologic impairment after subarachnoid hemorrhage (SAH). OBJECTIVE: To evaluate the impact of global and domain-specific cognitive impairment on functional recovery and quality of life (QOL) after SAH. METHODS: One hundred thirteen patients (mean age 49 years; 68% women) were evaluated 3 months after SAH. Three simple tests of global mental status and neuropsychological tests to assess seven specific cognitive domains were administered. Four aspects of outcome (global handicap, disability, emotional status, and QOL) were compared between cognitively impaired and unimpaired patients with analysis-of-covariance models controlling for age, race/ethnicity, and education. Multiple linear regression was used to evaluate the relative contribution of global and domain-specific cognitive status for predicting concurrent modified Rankin Scale (mRS) and Sickness Impact Profile (SIP) scores. RESULTS: Impairment of global mental status on the Telephone Interview of Cognitive Status (TICS) was associated with poor performance in all seven cognitive domains (all p < 0.0005) and was the only cognitive measure associated with poor recovery in all four aspects of outcome (all p < or = 0.005). Cognitive impairment in four specific domains was also associated with functional disability or reduced QOL. After accounting for global cognitive impairment with the TICS, however, neuropsychological testing did not contribute additional predictive value for concurrent mRS or SIP total scores. CONCLUSIONS: Cognitive impairment impacts broadly on functional status, emotional health, and QOL after SAH. The TICS may be a useful alternative to more detailed neuropsychological testing for detecting clinically relevant global cognitive impairment after SAH.