Using Mid-Sleep Time to Determine Chronotype in Young Adults with Insomnia-Related Symptoms

Abstract

The Munich Chronotype Questionnaire (MCTQ) uses sleep behavior to assess chronotype, but the extent to which such sleep behavior based assessments might be useful in populations with sleep disorders, such as insomnia, is currently unclear. We thus systematically assessed sleep disorders, MCTQ and the Morningness-Eveningness Questionnaire (MEQ), another behavioral preferencebased assessment of chronotype, in 310 individuals. In a smaller substudy (n = 121), we compared the MCTQ to sleep diaries in insomnia patients and good sleepers. Insomnia patients had overall lower consistency in chronotypes compared to good sleepers on the MCTQ compared to the MEQ, which was also evident when compared to sleep diaries. As insomnia disorder is characterized by time gaps spent awake during the night due to difficulty maintaining sleep, there may be limitations in using mid-sleep time as an accurate indicator of chronotype in insomnia patients. Our study suggests that the MCTQ should be used in conjunction with another existing questionnaire or assessment tool when assessing chronotype in insomnia patients.

Keywords

• Insomnia
• Sleep disorder
• Chronotype
• Circadian rhythm