Disrupted Sleep Patterns Linked To Worse Schizophrenia Spectrum Disorder: Study

The study reveals that too much sleep can have negative consequences on patients' SSD symptoms.

Schizophrenia

Researchers have found that patients with schizophrenia spectrum disorder (SSD), both residential and outpatient, displayed erratic sleep patterns and dysregulated transitions between sleep and wake cycles. The patients were also found to have excessively rigid daily routines predictive of worse SSD symptoms and correlating with poorer quality of life.

The international team of researchers from the University of Pittsburgh and Italy described patterns of disturbances and irregularities in daily rhythms of rest and activity shared across patients with SSD in a study published in the journal Molecular Psychiatry.

Previous research has suggested that people suffering from SSD have trouble falling asleep and get poorer rest than people without underlying mental health conditions. Further, sedative medications used to manage SSD symptoms are known to alter sleep and extend the time that patients spend resting up to 15 hours per day.

Too much sleep can have negative consequences on patients' SSD symptoms, said an associate professor of psychiatry and senior author of the study Fabio Ferrarelli.

"It's important to be mindful of how drugs that we prescribe to patients affect their health more broadly," he said. "Our study shows that a 12- to 15-hour sleep can be harmful, and it's important to avoid overprescribing sedatives and use the lowest dose possible."

In this study of 250 participants, which included almost 150 residential and outpatient SSD patients, the researchers measured participants' activity and rest throughout the day and night by asking them to wear a wristband that detects movement and acceleration. These devices measured activity and rest as proxies of wakefulness and sleep.

They found that both residential and outpatient SSD individuals tended to have fewer active hours during the day and spent more time sleeping or passively resting than healthy controls. The researchers also found that residential patients experienced more fragmented sleep and more abrupt transitions between rest and activity compared to the outpatient group.

Residential patients also displayed more rigid rhythms of daily rest and activity than outpatients, measures that correlated with negative mental health symptoms to a greater degree. These symptoms included reduced motivation to interact with others and blunted capacity for feeling pleasure.

"The consistency between the two patient cohorts was somewhat surprising to us," Ferrarelli said.

"But, interestingly, we found that residential patients had much more stable daily routines. We tend to think of stable routines as a good thing, but when these routines become too rigid, they can present a problem.” 

"In our study, this rigidity in daily rhythms was strongly correlated to the severity of negative mental health symptoms in residential patients with schizophrenia," said Ferrarelli.