University of Pittsburgh
Dr. Fabio Ferrarelli
The findings also showed that people with schizophrenia spectrum disorders (SSDs) who lived in residential facilities experienced rigid routines, which correlated with a higher degree of negative symptoms.
The rigid routines were problematic for the patients living in residential settings, lead investigator Fabio Ferrarelli, MD, PhD, told this news organization. Dr. Ferrarelli is an associate professor of psychiatry at the University of Pittsburgh.
“Engaging in different activities at different times in activities associated with motivation and social interaction – this helps to ameliorate difficult-to-treat negative symptoms,” he said.
The findings were published online in Molecular Psychiatry.
Need to increase activity levels
While there is no shortage of research on sleep disturbances among people with schizophrenia, research focusing specifically on rest-activity rhythm disturbances and their relationships to symptoms of schizophrenia has been limited by small sample sizes or the lack of a control group, the investigators note.
To address this research gap, the investigators recruited 230 patients with SSD from participating residential facilities and communities throughout Italy. The participants included 108 healthy control participants, 54 community-dwelling patients with SSD who were receiving outpatient services, and 68 patients with SSD who were living in residential facilities.
All participants wore an actigraph for 7 consecutive days so that investigators could monitor sleep-wake patterns.
Compared with healthy control participants, both SSD groups had more total sleep time and spent more time resting or being passive (P < .001). In contrast, healthy control participants were much more active.
Part of the explanation for this may be that most of the control participants had jobs or attended school. In addition, the investigators note that many medications used to treat SSD can be highly sedating, causing some patients to sleep up to 15 hours per day.
Among residential participants with SSD, there was a higher level of inter-daily stability and higher daily rest-activity-rest fragmentation than occurred among healthy control participants or community-dwelling patients with SSD (P < .001). There was also a higher level of negative symptoms among residential participants with SSD than among the community-dwelling group with SSD.
When the findings were taken together, Dr. Ferrarelli and his team interpreted them to mean that inter-daily stability could reflect premature aging or neurodegenerative processes in patients with more severe forms of schizophrenia.
Another explanation could be that the rigid routine of the residential facility was making negative symptoms worse, Dr. Ferrarelli said. It is important to add variety into the mix – getting people to engage in different activities at different times of day would likely help residential SSD patients overcome negative symptoms of the disorder.
Although participants were recruited in Italy, Dr. Ferrarelli said he believes the findings are generalizable.
Bidirectional relationship?
Commenting on the findings, Matcheri Keshavan, MD, professor of psychiatry at Harvard Medical School in Boston, said the results are consistent with “well-known clinical observations that SSD patients tend to spend more time in bed and have more dysregulated sleep.
Harvard Medical School
Dr. Matcheri Keshavan
“Negative symptoms are also common, especially in residential patients. However, it is difficult to determine causality, as we do not know whether excessive sleepiness and decreased physical activity cause negative symptoms, or vice versa, or whether this is a bidirectional relationship,” Dr. Keshavan said.
He emphasized that physical exercise is known to increase sleep quality for people with mental illness and may also improve negative symptoms. “A useful approach in clinical practice is to increase activity levels, especially physical activities like walking and gardening.”
Dr. Keshavan said he would like to see future research that focuses on whether an intervention such as aerobic exercise would improve sleep quality as well as negative symptoms.
He also said that future research should ideally examine the characteristics of sleep alterations in schizophrenia.
“For example, while sleep duration is increased in schizophrenia, studies suggest that time spent in deep sleep is reduced; sleep spindles, which are important for consolidating memory during sleep, are also reduced. Correcting these deficits may improve negative symptoms and cognitive deficits,” he added.
The study was funded by the Italian Ministry of Health and the National Institute of Mental Health. There were no conflicts of interest.
A version of this article first appeared on Medscape.com.