Brief communicationFrequent nightmares are associated with blunted cortisol awakening response in women

- Daily cortisol patterns were assessed on a working and leisure day in 188 women.
- The cross-sectional sample included 13 participants with frequent nightmares.
- Cortisol awakening response was smaller in the nightmare subgroup on the working day.
- Findings implicate that nightmares can be associated with HPA functioning.

Nightmares are relatively common sleep complaints that seem to be associated with affective distress. To date, few attempts have been made to link nightmares to the biological markers of the stress response, and the HPA response in particular. The present study examined the relationship between frequent nightmares and the cortisol awakening response (CAR) in a cross-sectional study of working women (N = 188). Analysis revealed that those who reported frequent nightmares (N = 13) showed a blunted CAR on a working day, compared to those who did not report nightmares. This result was independent of psychiatric symptoms, demographic variables, and lifestyle. Our preliminary findings suggest that decreased HPA reactivity might be a trait-like feature of women with frequent nightmares.