Exercise may improve positive and negative symptoms, as well as social and cognitive function, in youth at ultra-high risk (UHR) for psychosis, new research shows.
Results from a pilot study in 12 UHR adolescents and young adults who participated in a supervised aerobic exercise regimen showed improvements in clinical, social, and cognitive domains as well as changes in brain function in regions affected by psychosis.
"The results of this study suggest that exercise interventions are feasible within UHR samples and may help to improve important domains that are affected during the development of psychosis," the researchers, with first author Derek J. Dean, University of Colorado at Boulder, write.
"Unique to this study from others in psychosis is the examination of brain structure and functional connectivity, suggesting that exercise may lead to change in the functional organization of the cortical-hippocampal networks," they add.
The study was published in the November/December issue of the Journal of Clinical Psychiatry.
"Exciting developments" in patients with schizophrenia suggest that exercise interventions may improve a variety of symptoms, including cognitive, cardiovascular, social, and role functioning, as well as neurobiological domains, the authors write.
Previous research has suggested that adolescents at risk for psychosis are less physically active and are more likely to engage in poor health behaviors than their typically developing counterparts.
"Given the demonstrated benefits of exercise interventions in those with a formal psychotic disorder, the current study aims to test the feasibility of an aerobic exercise intervention prior to the onset of illness," the investigators note.
The researchers were interested not only in exploring the preventive impact of exercise on symptoms of schizophrenia but also the impact of exercise on the hippocampus, a region of the brain that is often impaired prior to the onset of psychosis.
"Examining the structure and function of the hippocampus may provide important insight into the neurobiological effects of exercise in UHR participants," they write.
To investigate the question, the investigators studied 12 adolescents or young adults with UHR (aged 16 to 24 years; mean age, 19.42 years; SD, 1.16) who reported having a predominantly sedentary lifestyle.
Participants completed the Structured Interview for Prodromal Syndromes both before and after the exercise intervention to enable the researchers to diagnose a prodromal syndrome and to track changes in positive and negative symptoms.
Social and role functioning were assessed through the Global Functioning Scale: Social and the Global Functioning Scale Role. The Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) was used to assess cognition.
Maximum oxygen uptake (Vo2max) was used to measure baseline and follow-up cardiovascular fitness. Vo2max levels also served as the basis for individually tailored exercise prescriptions.
Participants were randomly allocated to receive either moderate exercise (2 days a week at 65% of their Vo2max for a total of 24 sessions) or vigorous exercise (3 days a week at 85% of their Vo2max for a total of 36 sessions).
For the first 3 weeks, the exercise sessions lasted 15 minutes at an intensity level of 55% Vo2max. Exercise sessions were then gradually increased to 30 minutes at target intensity.
Participants could choose from several exercise modalities, including using a stationary bicycle, running or walking on treadmills, or using elliptical machines.
MRI and resting state functional connectivity MRI scannning was conducted at baseline and after exercise.
Of the participants (six male and six female), nine completed the exercise intervention and returned for follow-up assessment. In the moderate condition, seven participants completed the full 24 sessions; only two participants in the vigorous condition completed the full 36 sessions.
All three dropouts were in the vigorous condition group. Because so few participants completed all the sessions, "subsequent analyses of the exercise intervention collapsed across conditions," the researchers report.
There was a small to medium improvement in social and role functioning (d = 0.45 and d = 0.33, respectively).
Participants reported a medium to large decrease in positive symptoms after exercise and a small to medium decrease in negative symptoms (d = -0.61 and d = -0.47, respectively).
Participants showed significant improvements in after-trial composite score on the overall MATRICS cognitive battery (d = 1.74).
With regard to individual cognitive domains, there were improvements in working memory (d =0.92), verbal learning (d = 0.63), visual learning (d = 0.76), speed of processing (d = 1.30), attention/vigilance (d = 0.76), and reasoning and problem solving (d = 0.47). They showed no improvement in social cognition (d = -0.31).
Although there were no changes to hippocampal volume after exercise for either the left or right hippocampus (d = 0.18 and d = 0.31, respectively), the participants did show increased functional connectivity on the left hippocampus seed to bilateral occipital cortices after the exercise intervention.
There were no changes in connectivity in the right hippocampus seed.
Participants did not show improvement in physical fitness, as measured by V02max (d = -0.28).
"Few interventions can help with all of the early signs of psychosis; aerobic exercise may be a powerful treatment option with holistic benefits," the authors write.
"Consider exercise in the treatment planning for young adults showing early signs of psychosis," they advise.
Important Step Forward
Commenting on the study for Medscape Medical News, Joseph Firth, PhD, postdoctoral research fellow at the National Institute of Complementary Medicine, Western Sydney University, Australia, who was not involved with the study, called it "an important step forward for the field" because it "presents new insights into how best to use physical exercise in the treatment of psychiatric disorders."
He noted that recent research, including that of his group, has "indicated that using exercise in young adults who are presenting with psychosis for the first time may help improve early recovery from psychotic disorders, such as schizophrenia."
However, the current study "goes one step further than that, showing that exercise can be beneficial to individuals at high risk of developing psychosis."
He cautioned that the study "is only designed as a pilot trial, which prevents us from drawing definitive conclusions."
Even though the findings are "preliminary," they are "exciting," because they show the utility of moderate to vigorous exercise in improving psychological status and neurologic factors associated with prodromal psychosis.
The study has important take-home messages for clinicians working with these patients, who "should try their best to encourage these sorts of activities, along with helping patients to overcome the multitude of psychological, social, and physical health barriers they may face toward engaging in such types of exercise."
The authors cite small sample size and insufficient number of participants completing the intervention as study limitations.
They note that they are currently planning a larger randomized controlled trial that will "improve on these limitations."
The study was supported by the National Institute of Mental Health. Study author Vijay Mittal, PhD, has consulted for Takeda. The other investigators have disclosed no relevant financial relationships.
J Clin Psychiatry. 2017;78:e1167-e1173. Abstract
Medscape Medical News © 2018
Cite this: Exercise May Help Prevent Psychosis in High-Risk Youth - Medscape - Feb 13, 2018.