Living in higher latitude areas that receive less sunlight, could lead to a higher prevalence rate of obsessive-compulsive disorder (OCD), finds a new study published in the Journal of Obsessive-Compulsive and Related Disorders.
Meredith Coles, professor of psychology at Binghamton University, and colleagues hypothesized that the prevalence of obsessive-compulsive disorder would be positively correlated with latitude.
“The results of this project are exciting because they provide additional evidence for a new way of thinking about OCD,” said Coles.”Specifically, they show that living in areas with more sunlight is related to lower rates of obsessive-compulsive disorder .”
For the study, the researchers read through many papers that addressed OCD prevalence rates in certain places and then recorded the latitudes of each location.
Individuals with OCD commonly report not being able to fall asleep until later than desired. Often times, they will then sleep in very late in order to compensate for that lost sleep, thus adopting a delayed sleep-wake pattern that may have adverse effects on their symptoms.
“This delayed sleep-wake pattern may reduce exposure to morning light, thereby potentially contributing to a misalignment between our internal biology and the external light-dark cycle,” said Coles. “People who live in areas with less sunlight may have less opportunities to synchronize their circadian clock, leading to increased OCD symptoms.”
This misalignment is more prevalent at higher latitudes – areas where there is reduced exposure to sunlight – which places people living in these locations at an increased risk for the development and worsening of OCD symptoms. These areas subsequently exhibit higher lifetime prevalence rates of the disorder than areas at lower latitudes.
“First, we are looking at relations between sleep timing and OCD symptoms repeatedly over time in order to begin to think about causal relationships,” said Coles. “Second, we are measuring circadian rhythms directly by measuring levels of melatonin and having people wear watches that track their activity and rest periods. Finally, we are conducting research to better understand how sleep timing and OCD are related.”
Additionally, the team of researchers hopes that further study exploring exposure to morning light could help develop new treatment recommendations that would benefit individuals with obsessive-compulsive disorder.
“These findings are consistent with recent results suggesting that the timing of sleep may be important in OCD. Future work in this area is warranted, ” concluded the authors.
For more information log on to https://doi.org/10.1016/j.jocrd.2018.04.001