Refusal to participate in heart failure studies: do age and gender matter?

AIMS AND OBJECTIVES: The objective of this retrospective study was to evaluate reasons heart failure patients decline study participation, to inform interventions to improve enrollment. BACKGROUND: Failure to enrol older heart failure patients (age > 65) and women in studies may lead to sampling bias, threatening study validity. DESIGN: This study was a retrospective analysis of refusal data from four heart failure studies that enrolled 788 patients in four states. METHODS: Chi-Square and a pooled t-test were computed to analyse refusal data (n = 300) obtained from heart failure patients who were invited to participate in one of the four studies but declined. RESULTS: Refusal reasons from 300 patients (66% men, mean age 65·33) included: not interested (n = 163), too busy (n = 64), travel burden (n = 50), too sick (n = 38), family problems (n = 14), too much commitment (n = 13) and privacy concerns (n = 4). Chi-Square analyses showed no differences in frequency of reasons (p > 0·05) between men and women. Patients who refused were older, on average, than study participants. CONCLUSIONS: Some reasons were patient-dependent; others were study-dependent. With 'not interested' as the most common reason, cited by over 50% of patients who declined, recruitment measures should be targeted at stimulating patients' interest. Additional efforts may be needed to recruit older participants. However, reasons for refusal were consistent regardless of gender. RELEVANCE TO CLINICAL PRACTICE: Heart failure researchers should proactively approach a greater proportion of women and patients over age 65. With no gender differences in type of reasons for refusal, similar recruitment strategies can be used for men and women. However, enrolment of a representative proportion of women in heart failure studies has proven elusive and may require significant effort from researchers. Employing strategies to stimulate interest in studies is essential for recruiting heart failure patients, who overwhelmingly cited lack of interest as the top reason for refusal.

Nurse-Enhanced Computerized Cognitive Training Increases Serum Brain-Derived Neurotropic Factor Levels and Improves Working Memory in Heart Failure.

BACKGROUND: Memory loss is common in heart failure (HF) patients, but few interventions have been tested to treat it. The objective of this study was to evaluate efficacy of a cognitive training intervention, Brain Fitness, to improve memory, serum brain-derived neurotropic factor (BDNF) levels, working memory, processing speed, executive function, instrumental activities of daily living, mobility, depressive symptoms, and health-related quality of life. METHODS AND RESULTS: Twenty-seven HF patients were randomly assigned to Brain Fitness and health education active control interventions. Data were collected at baseline and 8 and 12 weeks. Linear mixed models analyses were completed. Patients in the Brain Fitness group were older with lower ejection fraction. At 12 weeks, a group by time interaction effect was found for serum BDNF levels (P = .011): serum BDNF levels increased among patients who completed Brain Fitness and decreased among patients who completed health education. No differences were found in memory, but a group by time interaction (P = .046) effect was found for working memory. CONCLUSIONS: Findings support efficacy of Brain Fitness in improving working memory and serum BDNF levels as a biomarker of intervention response. A randomized controlled study is needed among a larger more diverse group of HF patients.

Nurse-Enhanced Memory Intervention in Heart Failure: the MEMOIR study.

BACKGROUND: Many patients with heart failure (HF) have cognitive deficits, including memory loss. OBJECTIVES: The aim of this study was to evaluate the efficacy of a cognitive training intervention on memory (primary outcome), working memory, psychomotor speed, executive function, and performance of cognitive activities and instrumental activities of daily living (IADLs). METHODS AND RESULTS: Forty patients with HF were randomly assigned to the computerized plasticity-based cognitive training intervention called Brain Fitness or to the health education active control intervention. Advanced practice nurses made weekly home visits to assess symptoms and monitor intervention adherence. Patients completed demographic and clinical data (baseline), neuropsychologic tests (baseline and 8 and 12 weeks), and measures of cognitive and IADLs performance (baseline and 12 weeks) and satisfaction (12 weeks). Linear mixed models analyses indicated a significant group by time interaction for delayed recall memory (P = .032) and a significant time effect for total (list learning) (P < .001) and delayed (P = .015) recall memory, psychomotor speed (P = .029), and performance of IADLs (P = .006). Intervention adherence and patient satisfaction were high. CONCLUSIONS: To our knowledge, this was the first test of Brain Fitness in HF. Although it was a preliminary study with limitations, results support the need for a larger randomized controlled trial to determine whether the memory loss of HF is amenable to plasticity-based interventions.

APOE ε4 and Memory Among Patients With Heart Failure.

Twenty-three percent to 50% of heart failure (HF) patients have memory loss. Objectives were to (a) characterize major allelic frequency of 2 variants in apolipoprotein ( APOE) gene in HF patients, (b) evaluate differences in memory and serum brain-derived neurotrophic factor (BDNF) levels based on APOE ε4 allele(s), and (c) estimate effect sizes (ESs) and confidence intervals (CIs). In this pilot, 29 HF patients were enrolled and 26 completed. Recall and delayed recall memory were measured at baseline and 12 weeks. Serum was collected at baseline and 8 weeks. Seven (24.1%) patients had APOE ε4 allele. No significant differences were found in recall and delayed recall memory or serum BDNF levels based on APOE ε4 allele. ESs were small to medium; CIs indicated ES precision was small. Future studies are needed to fully understand how genotypic and neuropsychological phenotypic variables influence response to computerized cognitive training.

Cognitive dysfunction and self-care decision making in chronic heart failure: a review of the literature.

BACKGROUND: Memory and executive function may be associated with poorer self-care management behaviors (indicators of self-care decision making). Dysfunction of self-care decision making processes often results in worsening of heart failure symptoms that necessitates hospitalization for acute management. AIMS: The purposes of this literature review are to (a) synthesize the published literature (2000-2012) examining the relationship between cognitive dysfunction (CD) (executive function and memory) and self-care management decisions in heart failure (HF) patients; (b) identify gaps in knowledge; and (c) provide recommendations for future research to fill this gap. METHODS: Literature from January 2000-September 2012 was reviewed to determine the relationship between cognitive dysfunction and self-care decision making in patients with HF. Studies were included that used measures to examine the relationship between cognitive dysfunction and self-care decision making in patients with HF. RESULTS: The ability to identify a significant relationship between CD and self-care decision making processes was limited by the paucity of studies, small sample sizes, use of convenience samples and the use of single center recruitment sites. CONCLUSION: Despite the importance of memory and executive function in decision making, there is a paucity of studies describing the relationship between CD and self-care decision making processes. A knowledge gap exists regarding the relationship between CD and self-care decision making processes. The influence of executive function and memory on self-care decision making abilities needs further study in diverse populations, using standardized and valid measures for CD and self-care decision making processes.

Healthcare resource use among heart failure patients in a randomized pilot study of a cognitive training intervention.

OBJECTIVES: To compare healthcare resource use of patients with heart failure (HF) randomized to the cognitive training intervention and to the health education active control intervention in a randomized controlled pilot study. BACKGROUND: Cognitive training interventions may be efficacious and improve patients' memory and abilities to perform instrumental activities of daily living and self-care behaviors that may, in turn, lower healthcare resource use, but the influence of these interventions on healthcare resource use is unknown. METHODS: Thirty-four HF patients were randomized to the computerized plasticity-based cognitive training intervention called Brain Fitness and to the health education active control intervention and completed the study. The primary outcome variable for the study was memory (recall and delayed recall). The secondary purpose of the study that is the focus of this paper was to compare healthcare resource use between the two groups using the third-party payer perspective. Data were collected at baseline and at 8 and 12 weeks after baseline. Healthcare resources were priced at Medicare payment levels for services and average wholesale price for medications. RESULTS: Average costs of visits, procedures, and medications were similar between groups. Average costs of hospitalizations and tests, and therefore total costs, were half as much in the Brain Fitness group as compared to the active control group, but this difference was not significantly different from zero (p = 0.24). CONCLUSIONS: Larger randomized controlled trials are needed that include analyses of program costs and costs associated with medical and non-medical services in order to fully evaluate efficacy of this intervention.