Assessing Prevalence and Predictors of Impaired Executive Functioning in Four-year Stroke Survivors
Stroke is a cerebrovascular accident which may result in long-lasting consequences in the physical, emotional and cognitive wellbeing of a survivor’s life. Impaired executive function (EF) is a common form of cognitive impairment following a stroke which often results in the inability to sustain attention, initiate action, control emotions and motor coordination. These types of deficits can significantly impact a stroke survivor’s day-to-day living and quality of life. To date, there is a lack of data which examines the long-term effects of stroke on EF. The current study aimed to understand the predictors and prevalence of EF in four-year stroke survivors.
The current four-year follow-up study used a quantitative methodology. The sample (n=132) comprised of previously collected data, obtained from a sub-cohort drawn from a large population-based study, the fourth Auckland Regional Stroke Outcome Study (ARCOS-IV). Baseline data (at time of stroke or within two weeks) was obtained to examine factors which were associated with long-term impaired EF, four years following a stroke. EF was measured using the Comprehensive Trail Making Test (CTMT) at the four-year timepoint. A mean score of < 43 was indicative of impaired EF. Multivariate linear and logistic models were used to identify baseline predictors (reported as Odds Ratio [OR] with 95% confidence intervals [CI]) of impaired EF).
Four years after the stroke, nearly half (48.5%) of the stroke survivors experienced impaired EF (indicated by a score of <43 in the CTMT). Factors such as age, unemployment, a posterior circulation infarct (POCI), stroke in the non-frontal region, stroke in middle cerebral artery (MCA), having a history of previous stroke, history of hypertension, history of coronary artery disease, impaired baseline cognitive function (Montreal Cognitive Assessment [MoCA] scores ≤26) and lower quality of life (EuroQol Quality of Life Scale [EQ-5D] utility scores <0.50) were strongly associated with long-term impaired EF in stroke survivors. Multivariate logistic regression showed that older age (≥75 years; OR=4.41, CI 1.03-18.86), having a history of hypertension (OR=2.78, CI 1.12-6.88) and impaired cognitive function (MoCA scores ≤ 26; OR=14.24, CI 24.40-84.47) at the baseline (time of stroke) were the significant predictors of impaired EF at four years post-stroke.
This study revealed the prevalence and predictors associated with long-term impaired EF post-stroke. The implication of these findings may be beneficial for clinicians in identifying individuals at the acute phase of stroke who may be at greater risk of having persistent impairment in EF. This information may also assist in informing suitable rehabilitation and treatment strategies for stroke survivors that specifically target EF. In turn, stroke survivors may benefit from improved outcomes such as better functional wellbeing and improved quality of life. Additional research examining the trajectory of EF is warranted in order to determine the natural course of EF within stroke populations.