SOURCE: Levine DA, et al. Trajectory of cognitive decline after incident stroke. JAMA 2015;314:41-51.

It would likely come as no surprise that acute stroke can lower cognitive function. It might, however, come as a surprise that post-stroke incidence of cognitive impairment (that is, onset of cognitive impairment significantly after the period of acute stroke, rather than immediately post-stroke) is higher, and that once cognitive impairments ensue, the rate of further cognitive decline is faster in persons post-stroke than in controls.

These insights emerged from the REGARDS study (Reasons for Geographic and Racial Differences in Stroke, n = 30,239), which collected data on baseline cognitive function in adults > 45 years of age prior to incident stroke. Hence, the impact of stroke on cognition, as well as the impact on longer-term cognitive decline, is measurable within this data set. In this publication, persons with pre-existing cognitive impairment (that is, pre-stroke) were excluded from analysis.

Following an acute stroke, executive function declined significantly — more steeply than in controls; encouragingly, the capacity for new learning post-stroke did not decline.

Stroke is associated not only with acute cognitive decline in the immediate post-stroke period, but also with a more rapid slope of cognitive function decline over the long-term.