Patients with unipolar and bipolar disorders exhibited significantly lower heart rate variability compared to healthy controls during NREM and REM sleep (RMSSD p<0.001), but not during wakefulness.
Observational (n=180)
Does heart rate variability differ across consciousness states and sleep depth in individuals with sleep complaints and bipolar or unipolar depressive disorders compared to healthy controls?
Individuals with sleep complaints and depressive disorders exhibit reduced heart rate variability during NREM and REM sleep compared to healthy controls, suggesting a sleep-based autonomic signature of depressive states.
p-value: p=<0.001
OBJECTIVE: Autonomic nervous system dysfunction and reduced heart rate variability (HRV) often co-exist with mood disorders, a phenomenon likely influenced by sleep disturbances. This study investigated heart rate (HR) and HRV across wake, rapid eye movement (REM) sleep, and non-REM (NREM) sleep in individuals with sleep complaints and bipolar or unipolar depressive disorder. METHODS: Polysomnographic data was retrospectively collated for 120 adult patients with sleep complaints and depressive symptoms 60 diagnosed with bipolar disorder, 60 diagnosed with a unipolar depressive disorder, and 60 healthy controls. HR and time-based HRV variables were computed on 30-s segments and averaged across the night for wake, NREM and REM sleep. RESULTS: Significant group by consciousness state interactions showed that the unipolar and bipolar groups had lower standard deviation of normal-to-normal intervals root mean square of successive R-R interval differences compared to controls during NREM and REM sleep, but not during wake (SDNN: F(4, 330) = 3.0, p = .021, np2 = 0.035; RMSSD: F(4, 332) = 5.8, p < .001, np2 = 0.065). The magnitude of these group differences did not vary significantly between NREM 1, NREM 2 and NREM 3 sleep. These interactions persisted after excluding individuals taking 3rd generation antipsychotic, lithium, anticonvulsant, and cardiovascular medications. CONCLUSION: Although further work is required to account for the impact of psychotropic and cardiac medications, as well as manic and euthymic states, these findings suggest that the sleep-based autonomic signature of depressive states differs across different types of mood disorders and could potentially inform the development of biomarkers and therapeutic targets.
Leveille et al. (Fri,) conducted a observational in Sleep complaints and bipolar or unipolar depressive disorder (n=180). Bipolar or unipolar depressive disorder vs. Healthy controls was evaluated on Heart rate and time-based HRV variables (SDNN, RMSSD) across wake, NREM, and REM sleep (p=<0.001). Patients with unipolar and bipolar disorders exhibited significantly lower heart rate variability compared to healthy controls during NREM and REM sleep (RMSSD p<0.001), but not during wakefulness.