Relationships between Domain-specific Cognitive Function, Functional Performance and Life Satisfaction in Persons with Chronic Obstructive Pulmonary Disease (COPD)

Abstract

ABSTRACT Chronic Obstructive Pulmonary Disease (COPD) is a major cause of disability. Not only does COPD cause breathing difficulties, there are extrapulmonary effects including cognition with domain-specific cognition as our primary focus. Evidence suggests that COPD has negative effects on domain-specific cognition which may be related to declines in functional performance and life satisfaction. This three-paper dissertation includes a) a meta-analysis summarizing the effect size of changes in domain-specific cognition, b) a secondary analysis of the HRS data set examining longitudinal changes in domain-specific cognition in persons with and without COPD and c) a pilot study examining feasibility and acceptability computerized adaptive testing CAT) in persons with COPD and describing a preliminary relationship between domain-specific cognition, functional performance and life satisfaction. In the meta-analysis, differences indicated that persons with COPD had poorer performance than persons without COPD. No difference was found between the groups in the domains of executive function measured with verbal fluency animal or language measured with Boston Naming. A small effect size was found in memory and learning measured with Digit Span Forward (-0.298, 95% CI [ -0.480 - -0.114], p < 0.001) and executive function measured with Digit Span Backward (-0.352, 95% CI [-0.105 - -2.80], p < 0.001). Moderate effect sizes were found in attention measured with Trailmaking Test A (TMT-A) (-0.516, 95% CI [ -0.747 – -0.286], p < 0.001), in memory and learning measured with Wechsler Memory Scale immediate recall (-0.6, 95% CI [-0.480 – -0.114], p < 0.001) and delayed recall (-0.420, 95% CI [-0.610 – - 0.231], p < 0.001); in executive function measured with Trailmaking Test B (TMT-B) (-0.571, 95% CI [- 0.769 - - 0.374], p < 0.001) and large effect sizes were found in executive function measured with verbal letter fluency (-0.746, 95% CI [- 0.961 - - 0.530], p < 0.001) and processing speed measured with digit symbol (-0.923, 95% CI [ -0.769 - -0.374], p < 0.001). In the secondary data analysis, persons with COPD had significantly poorer performance in executive function and memory and learning. Both groups had significant declines over time, wiht a steeper decline immediate recall in the non-COPD group. In cross-sectional analysis, persons with COPD, no significant relationships between the cognitive domains and life satisfaction to mediate. In the non-COPD group, there was a relationship between delayed recall and life satisfaction that was fully mediated by activities of functional performance. Hopelessness explained a significant portion of the variance in cognition in both groups. Semipartial in the COPD group, hopelessness uniquely contributed to immediate recall (7%) and delayed recall (9%) and explained very little in the non-COPD group (<1%). Finally, a pilot study examined feasibility and acceptability of computer adaptive testing (CAT) in COPD. On a scale of 0 - 5, the CAT had a 4.3 overall impression indicating acceptability. Only processing speed approached the level of significance with 47.5% of persons below norm. Findings suggest that persons with COPD have domain-specific cognitive deficits that are greater than those occurring in normal aging.