Insomnia symptoms and heart rate recovery among patients in cardiac rehabilitation

Abstract

Insomnia symptoms (i.e., difficulty falling asleep, difficulty staying asleep, and early morning awakenings) are common among people with cardiovascular disease, and have been linked to adverse cardiovascular health outcomes. Reduced parasympathetic tone is one pathway through which risk may be conferred. The purpose of this study was to evaluate whether insomnia symptoms are associated with lower parasympathetic tone in cardiac rehabilitation patients with suspected insomnia. Participants (N = 121) completed a self-report measure of insomnia severity. 1-min heart rate recovery (HRR), an index of parasympathetic tone, was obtained during a maximal exercise test. Difficulty falling asleep, but not difficulty staying asleep or early awakenings, was associated with attenuated 1-min HRR. When analyses were restricted to participants with moderate and severe insomnia severity (n = 51), the strength of this association increased. In a sample of cardiac rehabilitation patients with insomnia, only the symptom of difficulty falling asleep was associated with lower parasympathetic tone, suggesting that individual insomnia symptoms may show specificity in their associations with physiological mechanisms.

Insomnia and Risk of Cardiovascular Disease

“…49 A recent cross-sectional study demonstrated an association between difficulty falling asleep and reduced parasympathetic tone (measured by 1-min heart rate recovery from maximal exercise test) in patients undergoing cardiac rehabilitation who had moderate to severe insomnia. 50 In this study, insomnia severity was ascertained using the Insomnia Severity Index, a wellvalidated 22,51 questionnaire commonly used to screen and grade insomnia. A study of > 500 participants in the Multiethnic Study of Atherosclerosis showed that participants who slept # 7 hours per night and reported insomniac symptoms had greater heart rate orthostatic reactivity and a high frequency of heart rate variability reactivity to mental stress than participants who slept > 7 hours per night with no insomniac symptoms.…”

The Herbal Formula CWBSD Improves Sleep Quality Dependent on Oral Microbial Type and Tongue Diagnostic Features in Insomnia

“…Current evidence indicates that autonomic nerve dysfunction is a potential mechanism of insomnia, and therefore, insomnia patients tend to have increased sympathetic and reduced parasympathetic tones [ 57 ]. In HRV, high-frequency power (HF) is attributed to parasympathetic nerve activity, while low-frequency power (LF) indicates functions related to sympathetic and vagal nerves.…”

The Herbal Formula CBD Improves Sleep Quality Dependent on Oral Microbial Type and Tongue Diagnostic Features in Insomnia

“…Current evidence indicates that autonomic nerve dysfunction is a potential mechanism of insomnia, and therefore, insomnia patients tend to have increased sympathetic and reduced parasympathetic tones (57). In HRV, high-frequency power (HF) is attributed to parasympathetic nerve activity, while lowfrequency power (LF) indicates functions related to sympathetic and vagal nerves.…”