Abstract
Background: Patients with chronic heart failure (HF) have cognitive deficits in memory, psychomotor speed, and executive function and poor health-related quality of life (HRQL), but the association between cognitive deficits and HRQL is unknown.
Objectives: The objectives of this study were to (1) evaluate the relationship between HF severity, age, comorbidities, and cognitive deficits and HRQL among patients with chronic HF and (2) examine whether cognitive deficits mediated the relationship between HF severity and HRQL.
Design and Sample: This study was part of a larger explanatory study; 249 patients with HF completed face-to-face interviews.
Methods: Measures of HF severity, comorbidity (multiple comorbid conditions, hypertension, and depressive symptoms), cognitive function (domains of language, working memory, memory, psychomotor speed, and executive function), and HRQL were obtained. Clinical variables were abstracted from patients' records. Statistical analyses were conducted using descriptive statistics, Pearson correlation coefficients, and multiple linear regression analyses.
Results: Overall, the HRQL of patients was moderately poor. Heart failure severity, age, depressive symptoms, and total recall memory explained 55% of the variance in HRQL, but the contribution of memory was minimal (1%). Patients with more severe HF, younger age, and more depressive symptoms had poorer HRQL. Other cognitive function variables, multiple comorbidity, and hypertension were not significant explanatory variables for HRQL. Cognitive deficits did not mediate the relationship between HF severity and HRQL.
Conclusions: Novel interventions targeted at improving HRQL continue to be urgently needed, particularly among younger patients and patients with depressive symptoms. Measures of HRQL are not sufficient as outcomes when investigating cognitive deficits in HF. Investigators need to include outcome measures of patients' actual abilities to perform daily activities and HF self-care.