Cognitive Function Does Not Impact Self-reported Health-Related Quality of Life in Heart Failure Patients.

BACKGROUND: Adults with heart failure (HF) often demonstrate impairment across multiple domains of cognitive functioning and report poor health-related quality of life (HRQoL). Previous researchers have found that cognitive deficits were generally not associated with HRQoL in a carefully evaluated sample. The exception was memory, which was only weakly associated with HRQoL. However, cognitive deficits interfere with self-care and disease self-management, which could be expected to affect HRQoL. OBJECTIVE: We sought to verify this counterintuitive finding in a large well-characterized sample of HF patients using a well-validated neuropsychological battery. METHODS: Participants were 302 adults (63% male) predominately white (72.5%) HF patients (68.7 ± 9.6 years) recruited from 2 medical centers. Self-reported HRQoL was assessed using the Kansas City Cardiomyopathy Questionnaire. Participants completed a neuropsychological battery examining attention, executive function, memory, and visuospatial functioning. Hierarchical multiple linear regression was used for analyses. RESULTS: Mild global cognitive impairment was observed in 29.5% of the sample (Modified Mini-Mental State [3MS] Examination score <90). Controlling for gender, depression, HF severity, premorbid IQ, comorbidities, and education, only executive function predicted HRQoL, ß = .17, P < .05. However, executive function accounted for only 0.6% of the variance in HRQoL. CONCLUSION: Cognitive function generally did not predict HRQoL in HF patients. The correlates of HRQoL in HF do not appear to include mild cognitive impairment. Other factors may play a bigger role such as disease severity, age, and depressive symptoms. Future studies should investigate modifiable determinants of HRQoL in HF patients, toward the goal of finding interventions that preserve HRQoL during this chronic illness.

Cognitive Function in Heart Failure Is Associated With Nonsomatic Symptoms of Depression But Not Somatic Symptoms.

BACKGROUND: Patients with heart failure (HF) have high rates of cognitive impairment and depressive symptoms. Depressive symptoms have been associated with greater cognitive impairments in HF; however, it is not known whether particular clusters of depressive symptoms are more detrimental to cognition than others. OBJECTIVE: The aim of this study was to identify whether somatic and/or nonsomatic depressive symptom clusters were associated with cognitive function in persons with HF. METHODS: Participants were 326 HF patients (40.5% women, 26.7% non-white race-ethnicity, aged 68.6 ± 9.7 years). Depressive symptoms were measured using a depression questionnaire commonly used in medical populations: the Patient Health Questionnaire-9. Somatic and nonsomatic subscale scores were created using previous factor analytic results. A neuropsychological battery tested attention, executive function, and memory. Composites were created using averages of age-adjusted scaled scores. Regressions adjusting for demographic and clinical factors were conducted. RESULTS: Regressions revealed that Patient Health Questionnaire-9 total was associated with attention (ß = -.14, P = .008) and executive function (ß = -.17, P = .001). When analyzed separately, the nonsomatic subscale, but not the somatic symptoms subscale (P values ≥ .092), was associated with attention scores (ß = -.15, P = .004) and memory (ß = -.11, P = .044). Both nonsomatic (ß = -.18, P < .001) and somatic (ß = -.11, P = .048) symptoms were related to executive function. When included together, only the nonsomatic symptom cluster was associated with attention (ß = -.15, P = .020) and executive function (ß = -.19, P = .003). CONCLUSIONS: Greater overall depressive symptom severity was associated with poorer performance on multiple cognitive domains, an effect driven primarily by the nonsomatic symptoms of depression. CLINICAL IMPLICATIONS: These findings suggest that screening explicitly for nonsomatic depressive symptoms may be warranted and that the mechanisms underlying the depression-cognitive function relationship in HF are not solely related to sleep or appetite disturbance. Thus, interventions that target patients' somatic symptoms only (eg, poor appetite or fatigue) may not yield maximum cognitive benefit compared with a comprehensive treatment that targets depressed mood, anhedonia, and other nonsomatic symptoms.