Effect of Sleep Intervention Programs during Cardiac Rehabilitation on the Sleep Quality of Heart Patients

Assessing Risk of Health Outcomes From Brain Activity in Sleep: A Retrospective Cohort Study

Background and Objectives

Patterns of electrical activity in the brain (EEG) during sleep are sensitive to various health conditions even at subclinical stages. The objective of this study was to estimate sleep EEG-predicted incidence of future neurologic, cardiovascular, psychiatric, and mortality outcomes.

Methods

This is a retrospective cohort study with 2 data sets. The Massachusetts General Hospital (MGH) sleep data set is a clinic-based cohort, used for model development. The Sleep Heart Health Study (SHHS) is a community-based cohort, used as the external validation cohort. Exposure is good, average, or poor sleep defined by quartiles of sleep EEG-predicted risk. The outcomes include ischemic stroke, intracranial hemorrhage, mild cognitive impairment, dementia, atrial fibrillation, myocardial infarction, type 2 diabetes, hypertension, bipolar disorder, depression, and mortality. Diagnoses were based on diagnosis codes, brain imaging reports, medications, cognitive scores, and hospital records. We used the Cox survival model with death as the competing risk.

Results

There were 8673 participants from MGH and 5650 from SHHS. For all outcomes, the model-predicted 10-year risk was within the 95% confidence interval of the ground truth, indicating good prediction performance. When comparing participants with poor, average, and good sleep, except for atrial fibrillation, all other 10-year risk ratios were significant. The model-predicted 10-year risk ratio closely matched the observed event rate in the external validation cohort.

Discussion

The incidence of health outcomes can be predicted by brain activity during sleep. The findings strengthen the concept of sleep as an accessible biological window into unfavorable brain and general health outcomes.

Non-pharmacological interventions for improving sleep outcomes among patients with a diagnosis of coronary artery disease: a systematic review and meta-analysis

AIMS

To determine the effectiveness of non-pharmacological interventions on sleep outcomes among patients with coronary artery disease and recognize pertinent characteristics that potentially affect the effectiveness of such interventions.

METHODS AND RESULTS

Relevant studies conducted before 27 April 2022 were identified through four core electronic databases using terms related to coronary artery disease, sleep outcomes, and randomized controlled trials. Two authors independently conducted study selection, data extraction, and risk-of-bias assessment. Meta-analysis, sub-group analysis, publication bias analysis, and sensitivity analysis were conducted using R version 4.2.2. Of the 4755 retrieved articles, 42 studies were selected for systematic review and 30 studies were included in the meta-analysis. The findings of this study revealed that non-pharmacological interventions significantly improved self-reported sleep quality (standardized mean difference = -0.85, 95% confidence interval -1.08, -0.63), but had no effects on objectively measured sleep efficiency and duration. Regarding the types of interventions involved, environmental control was the most effective in improving self-reported sleep quality, followed by relaxation, self-care behaviour management, and relaxation and cognitive/psychological complex interventions. Through subgroup analysis, we did not find any covariates that were significantly related to self-reported sleep quality.

CONCLUSION

Non-pharmacological interventions have been shown to play beneficial roles in improving self-reported sleep quality among patients with coronary artery disease. Additional studies are required to elucidate the effect of non-pharmacological interventions on objectively measured sleep outcomes and to characterize their optimal frequencies and durations.

REGISTRATION

PROSPERO CRD42022366851.

Effects of Cardiac Rehabilitation on Sleep Quality in Heart Disease Patients with and without Heart Failure

Insomnia is a modifiable cardiovascular risk factor. Previous studies suggested that attending a cardiac rehabilitation program may improve sleep quality in cardiac patients and pointed out the association between heart failure and poor sleep quality. The primary aim of this study was to evaluate sleep quality in patients attending a Multidisciplinary Cardiac Rehabilitation Program (MRCP), and to compare sleep quality between patients with and without heart failure. A prospective observational study was carried out on a consecutive sample of 240 patients attending an 8-week MRCP; 50 patients (20.8%) were included due to heart failure (NYHA stages I-III) and the rest of them after having undergone any revascularization procedure or valvular surgery. Before and after the completion of the MRCP, the quality of sleep was assessed by the Pittsburgh Sleep Quality Index (PSQI) score. Post-intervention global PSQI scores were statistically significantly lower than those of pre-intervention (p = 0.008), but only 60 patients (25%) registered a clinically significant improvement. When comparing patients with heart failure with those without, no differences in sleep quality were found. This suggests that only a small percentage of patients can achieve clinically significant improvements in sleep quality attending conventional MCRP. Suggestions for future research are given.