Associations between age, vasospasm, and cognitive deficits after ruptured aneurysm repair
Although vasospasm has been postulated as a risk for development of neuropsychological deficits after rupture and repair of intracerebral aneurysms, there is little empirical support for this hypothesis. To determine the risk of vasospasm for persistent cognitive deficits, we studied 16 patients, age 30–77, with daily TCD evaluations after aneurysm clipping, and administered a battery of neuropsychological tests (clusters of language, spatial, and memory tests) 3 months post-operatively. We calculated Pearson correlations between neuropsychological test cluster scores (age-corrected) and: (1) #days in vasospasm by TCD criteria; (2) #vessels in vasospasm by TCD; and (3) maximum velocity in each major vessel. Results: Vasospasm in left or right ICA (C1) or MCA (M1) was negatively correlated with both language (r=.57-.64; p<.02)and spatial(r=.53-.57; p<.02), but not memory, test scores compared to age norms. Paradoxically, however, both #days in vasospasm (any vessel) and #vessels in vasospasm were positively correlated with both language and spatial scores (r=.56-.60; p<.03 each). That is, more diffuse/longer duration vasospasm was associated with better scores. This result was entirely accounted for by age. Age was negatively correlated with both #days in vasospasm (r=-.564; p<.03) and #vessels in vasospasm (r=-.555; p<.030). Likewise, age was negatively correlated with age-corrected scores on all neuropsychological tests. That is, older patients had less diffuse vasospasm, for fewer days, but nevertheless had more severe cognitive deficits (relative to age norms) at 3 months post surgery. When we controlled for age, there were no significant correlations between #days or #any vessels in vasospasm and neuropsychological scores. Conclusions: Across all ages, severity of vasospasm in left or right ICA (C1) or MCA (M1) was associated with lower age-corrected scores on language and spatial tests. Older patients had fewer vessels and fewer days in vasospasm of any vessel(possibly due to lower vascular reactivity or attenuated inflammatory response associated with aging), but nonetheless showed more significant deficits on neuropsychological tests.