Are We Asking the Right Questions? Sex Specificity of Dream Characteristics in Probable Rapid Eye Movement Sleep Behavior Disorder.

BACKGROUND

Dream enactment behavior is a common feature of rapid eye movement (REM) sleep behavior disorder (RBD); however, there has been surprisingly little focus on sex differences in dream characterization in RBD. This is important to evaluate further, as it is possible that females and males have different dream characteristics in RBD, and screening questionnaires that focus on aggressive and injurious dream features (common to males) may be insensitive to detect RBD in female populations.

OBJECTIVE

The aim was to determine if dream characteristics are sex specific in people with "probable" RBD (pRBD) and older adults from a large community cohort.

METHODS

Adults aged ≥50 years were recruited from the Tasmanian community, Australia, to complete the REM Sleep Behavior Disorder Single-Question Screen (RBD1Q, to identify pRBD) and the Mannheim Dream Questionnaire (MADRE). Correlations between the MADRE and various outcomes were analyzed using multiple linear regression and χ2 tests for binary response questions, with Bonferroni correction P < 0.002 denoting significance.

RESULTS

One thousand eight hundred nine participants were recruited, and 7.1% (129) screened positive for pRBD. In the pRBD group, females reported more nightmares related to waking-life experiences (P < 0.001) than males. The pRBD group recalled dreams more often (P < 0.001) and experienced more lucid dreams (P < 0.001) and more nightmares during childhood (P < 0.001) than non-pRBD controls.

CONCLUSION

We found sex-specific differences in dream characteristics in pRBD and in pRBD versus controls. This is relevant to RBD screening questionnaires as questions on nightmares related to waking life may aid identification of females with pRBD.