Background: Alterations in circadian rhythms can have profound effects on mental health. High co-morbidity for psychiatric disorders has been observed in patients with circadian rhythm disorders, such as delayed sleep phase disorder (DSPD), and in those with an evening-type circadian preference. The aim of this study was to systematically determine the prevalence and type of Diagnostic and Statistical Manual of Mental Disorders fourth edition (DSM IV) Axis-I disorders in those with DSPD compared to evening-type controls. Methods: Forty-eight DSPD and 25 evening-type participants took part in this study. Sleep and wake parameters were assessed with actigraphy, diary and questionnaires (Pittsburgh Sleep Quality Index (PSQI) and Functional Outcomes of Sleep Questionnaire (FOSQ). Evening-type preference was defined by the Horne-Ostberg questionnaire. DSPD was determined by an interview according to International Classification of Sleep Disorders criteria. Current and past diagnoses of psychiatric disorders were assessed with a Structured Clinical Interview for DSM-IV disorders. Results: DSPD was associated with a later wake time, longer sleep time, higher PSQI score and lower Horne-Ostberg and FOSQ scores compared to evening-types. There were no significant differences in the prevalence or type of Axis-I disorders between those with DSPD or evening-type preference. Over 70% of participants met criteria for at least one past Axis-I disorder. Approximately 40% of both the DSPD and evening-types met criteria for a past diagnosis of mood, anxiety (most frequently phobia) or substance-use disorders. Evening types were more likely to have a past diagnosis of more than one Axis-I disorder. Conclusions: These results highlight the important link between circadian rhythms and mental disorders. Specifically, an evening circadian chronotype regardless of DSPD status is associated with a risk for anxiety, depressive or substance-use disorders.
Bibliographical noteFunding Information:
The authors would like to acknowledge the contribution of Gregory Kodesh for aid with data collection and Sridhar Jatla, Prasanth Manthena and Ramadevi Gourineni for diagnosis of DSPD status. Funding for this project was provided by a Grant awarded to P.C. Zee (PI) from the National Institutes of Health , Grant R01 HL069988 support for K Baron 1K23HL109110-01, 5K12 HD055884, NIH T32 HS00078 support for K Baron 1K23HL109110-01, 5K12 HD055884, NIH T32 HS00078.
- Delayed sleep phase disorder
- Evening-type preference
- Psychiatric disorders