UC Berkeley

Sleep is a vital biological function, necessary to physical and psychological health. Caregivers of patients with neurodegenerative disease suffer from chronically poor sleep. Research suggests that emotions can influence sleep quality, but little research has examined this relationship in caregivers of patients with neurodegenerative disease. In the present study, objective laboratory measures of emotion and emotion regulation, and a combination of prospectively-reported and objectively-measured sleep quality, were used to examine this important relationship. Caregivers’ physiological and expressive reactivity to emotion-eliciting films was measured in the laboratory. Caregivers’ physiological reactivity to two emotion regulation tasks (suppression, amplification) was also measured. During the week following laboratory testing, caregivers wore an actigraphy wristwatch, which recorded movement and ambient light in order to measure sleep quality, and completed a daily sleep diary. Data were analyzed to test the hypotheses that (a) greater physiological reactivity and (b) greater expressive reactivity would be associated with worse sleep quality during the following week, and to determine whether physiological reactivity to the emotion suppression and amplification tasks was associated with sleep quality.

Sleep quality in the present study was largely similar to and for some measures, better than sleep in previously published samples of non-caregiver older adults. Results partially supported the hypothesis that greater physiological reactivity to the films would be associated with worse sleep quality. Greater physiological reactivity to a film chosen to elicit distress was associated with worse sleep quality, whereas greater physiological reactivity to a film chosen to elicit sexual arousal was associated with better sleep quality. Exploratory analyses revealed that the results were reliable across caregivers for two of the three largest neurodegenerative diagnostic groups in the sample, and across caregiver sex. Neither expressive reactivity to the films, nor physiological reactivity to the emotion suppression or amplification tasks, was associated with sleep quality. These findings indicate that caregivers’ physiological reactivity to distressing and sexually arousal stimuli are associated with sleep quality. Interventions that reduce physiological reactivity to distressing stimuli, or that increase caregivers’ physiological reactivity to sexually-arousing stimuli, may improve caregiver sleep and its downstream effects.