Acute stress alters autonomic modulation during sleep in women approaching menopause

Abstract

Hot flashes, hormones, and psychosocial factors contribute to insomnia risk in the context of the menopausal transition. Stress is a well-recognized factor implicated in the pathophysiology of insomnia; however the impact of stress on sleep and sleep-related processes in perimenopausal women remains largely unknown. We investigated the effect of an acute experimental stress (impending Trier Social Stress Task in the morning) on presleep measures of cortisol and autonomic arousal in perimenopausal women with and without insomnia that developed in the context of the menopausal transition. In addition, we assessed the macro- and micro-structure of sleep and autonomic functioning during sleep. Following adaptation to the laboratory, twenty two women with (age: 50.4 ± 3.2 y) and eighteen women without (age: 48.5±2.3 y) insomnia had two randomized in-lab overnight recordings: baseline and stress nights. Anticipation of the task resulted in higher pre-sleep salivary cortisol levels and perceived tension, faster heart rate and lower vagal activity, based on heart rate variability measures, in both groups of women. The effect of the stress manipulation on the autonomic nervous system extended into the first four hours of the night in both groups. However, vagal tone recovered four-six hours into the stress night in controls but not in the insomnia group. Sleep macrostructure was largely unaltered by the stress, apart from a delayed latency to REM sleep in both groups. Quantitative analysis of non-rapid eye movement sleep microstructure revealed greater electroencephalographic (EEG) power in the beta1 range (15-≤23Hz), reflecting greater EEG arousal during sleep, on the stress night compared to baseline, in the insomnia group. Hot flash frequency remained similar on both nights for both groups. These results show that presleep stress impacts autonomic nervous system functioning before and during sleep in perimenopausal women with and without insomnia. Findings also indicate that women with insomnia had increased EEG arousal and lacked recovery in vagal activity across the stress night suggesting a greater sensitivity to stress in this group.

Menstrual cycle-related variation in autonomic nervous system functioning in women in the early menopausal transition with and without insomnia disorder

“…These findings extend our previous work showing altered regulatory control of blood pressure during sleep (de Zambotti et al, IN PRESS) and an altered autonomic profile in response to pre-sleep stress, in women with MTI (de Zambotti et al, 2016). Autonomic hyperarousal is thought to play a role in the etiology of insomnia disorder, with several studies finding higher HR and abnormal ANS modulation in insomnia disorder in mixed groups of men and/or women of varying ages (Bonnet and Arand, 2010; Riemann et al, 2015).…”

“…None of the previous studies focused on MTI, although we recently reported that women with MTI have elevated beta EEG activity in REM sleep reflecting heightened EEG arousal compared to controls (Baker et al, 2015). We also previously demonstrated (de Zambotti et al, 2016) that women with MTI have blunted vagal recovery during the night following an experimental pre-sleep stressor, suggesting altered ANS function, at least in response to stress.…”

Sleep problems during the menopausal transition: prevalence, impact, and management challenges

“…Chronic stress could add a layer of complexity to PSG sleep disturbance in insomnia disorder in midlife women – Hall et al 138 found that women with more chronic stress exposure over a 9-year period had greater PSG-assessed WASO (as well as being more likely to have insomnia) than participants with moderate stress exposure. We also found that women with insomnia showed less within-night recovery in autonomic vagal functioning following pre-sleep acute stress exposure 144 as well as raised HR 145 and raised blood pressure 91 during sleep relative to women without insomnia, also in the menopausal transition.…”

Sleep, Health and Wellness at Work: A Scoping Review

“…In premenopausal women, hormonal changes, flushes and psychosocial factors contribute to increasing the frequency of insomnia. It has been demonstrated that there is more electro-encephalographic activation and a lack of vascular activity recovery after acute stress in women with insomnia, indicating that the latter contributes to increasing stress sensitivity [ 110 ].…”