Obsessive-Compulsive Symptoms and Morningness-Eveningness Variation in Healthy Individuals

Abstract

The present study proposes to answer the following question: Do people without OCD and a late chronotype have more obsessive-compulsive symptoms than people with earlier chronotypes? Individuals with obsessive-compulsive disorder (OCD) are more likely than healthy individuals to exhibit habitually delayed sleep schedules, sometimes diagnosed as Delayed Sleep Phase Disorder. Additional research suggests that this trend may also be present in people without OCD. Individuals with habitually later bedtimes may exhibit more subclinical obsessive-compulsive symptoms than those with earlier bedtimes. Given that high levels of subclinical symptoms may constitute a risk factor for developing OCD, it is important to understand if delayed sleep schedules play a role in the progression of the disorder from subclinical to clinical. Individual preference for later sleep and wake patterns, called eveningness or late chronotype, has been associated with worse mental health outcomes such as depression, but has yet to be compared with chronotype in healthy individuals. This study surveyed 57 participants recruited online from the general population to submit reports on their sleep quality, chronotype, and obsessive-compulsive symptoms. Participants also submitted additional daily sleep diaries for one week to confirm sleep habits. Overall, increased eveningness significantly predicted increased reports of obsessive-compulsive symptoms and worse sleep quality. However, poorer sleep quality was a more substantial indicator of symptoms than eveningness, and grouping individuals into chronotype categories was less predictive of symptoms than the morningness-eveningness scores. Sleep midpoint, a value that is indicative of differences in sleep schedules, was strongly associated with chronotype but was also a better indicator of symptom reports. Total sleep duration, age, and gender did not appear to significantly influence the outcome variables. More research is needed to better understand these relationships in a healthy population sample, especially using objective measurements of sleep timing and quality.