Deficits in Self-Reported Initiation Are AssociatedWith Subsequent Disability in ICU Survivors

Abstract

Objective: To determine whether deficits in a key aspect of executive functioning, namely, initiation, were associated with current and future functional disabilities in intensive care unit survivors.

Methods: A nested substudy within a 2-center prospective observational cohort. We used 3 tests of initiation at 3 and 12 months: the Ruff Total Unique Design, Controlled Oral Word Association, and Behavior Rating Inventory of Executive Function initiation. Disability in instrumental activities of daily living (IADL) was measured with the Functional Activities Questionnaire. We used a proportional odds logistic regression model to evaluate the association between initiation and disability. Covariates in the model included age, education, baseline Functional Activities Questionnaire, pre-existing cognitive impairment, comorbidities, admission severity of illness, episodes of hypoxia, and days of severe sepsis.

Results: In 195 patients, after adjusting for covariates, only the Behavior Rating Inventory of Executive Function initiation was associated with disability at any time point. Comparing the 25th vs the 75th percentile scores (95% confidence interval) of the Behavior Rating Inventory of Executive Function initiation at 3 months, patients with worse initiation scores had 5.062 times the odds (95% confidence interval: 2.539, 10.092) of disability according to the Functional Activities Questionnaire at 3 months, with similar odds at 12 months (odds ratio: 3.476, 95% confidence interval: 1.943, 6.216). Worse Behavior Rating Inventory of Executive Function initiation scores at 3 months were associated with future disability at 12 months odds ratio (95% confidence interval) 5.079 (2.579, 10.000).

Conclusions: Executive function deficits acquired after a critical illness in the domain of initiation are common in intensive care unit survivors, and when they are identified via self-report tools, they are associated with current and future disability in instrumental activities of daily living.

Trial registration: ClinicalTrials.gov NCT00392795.

Keywords: cognition; critical illness; executive function; function.

Copyright © 2018 Academy of Consultation-Liaison Psychiatry. All rights reserved.

Figures

Figure 1.

Flow of BRAIN-ICU participants into this executive function sub-study.

Figure 2.

Initiation measures and odds of worse FAQ score at 3 and 12 months In the figure above, the black dots represent Odds Ratio values (comparing the 25th versus the 75th percentile of initiation measure (Ruff, COWA or BRIEF-I) versus FAQ at different points above in time) which is fully described above in Table 2, the horizontal solid black lines represents the 95% Confidence Interval, with the central dot indicating the OR and the vertical dashed black line represents a referent Odds Ratio of 1. Of note, only the BRIEF-I measure, a subjective measure of initiation, was significantly associated with FAQ score at any time point, suggesting that a patient’s individual appraisal of their ability to initiate tasks, etc., is more reflective of functional disability both now and in the future than objective measures alone.