Exercise as it relates to Disease/Improving cognitive performance and psychopathology in depressive and schizophrenia patients through aerobic exercise

The following Wikibooks page is an analysis of the journal article 'Effects of Aerobic Exercise on Cognitive Performance and Individual Psychopathology in Depressive and Schizophrenia Patients' (Oertel-Knöchel et al., 2014). This analysis was performed by u3049173.

What is the background to this research?
With around 20% of Australian adults experiencing some form of mental illness in a 12 month period, developing effective treatments to reduce the severity of symptoms and improve quality of life is vital. Conditions such as Major Depressive Disorder (MDD) and Schizophrenia (SZ) account for 6% and 1% of the total number of individuals suffering from mental illnesses respectively, and are characterised by both cognitive deficits and specific psychopathological symptoms.

Major Depressive Disorder

 Schizophrenia Symptoms  Individuals suffering from MDD and SZ are twice as likely to experience homelessness and roughly 12 times more likely to commit suicide when compared to the healthy population. In Australia mental illness accounts for approximately 20 billion dollars in government spending for support services/treatments and lost productivity as a result of a decline in work performance. While there are many effective treatment options to improve the psychopathological symptoms of MDD and SZ, no known pharmacological treatment exists for improving cognitive performance, which has been shown to be associated with functional outcomes such as work performance and independent living. With previous studies showing a strong link between exercise and improved cognitive performance in healthy individuals and those living with diseases such as dementia, researchers are becoming increasingly interested in whether exercise can have the same effect on patients with MDD and SZ.

Where is the research from?
Oertel-Knöchel et al. conducted this study at Goethe-University in Frankfurt, Germany. All participants were inpatients of the Department of Psychiatry at Goeth-University. Authors received approval for experimental procedures from the ethical board and medical department at Goethe-University and declared no conflicts of interest.

What kind of research was this?
This study was a randomised control study (RCT). 51 participants (22 MDD, 29 SZ) were selected based on strict criteria regarding diagnosis of their disorder and randomly allocated to a group receiving 1 of 2 interventions or a control group, receiving no treatment. The random allocation of participants and inclusion of a control group reduces bias and allows for comparison between interventions and disorders.

What did the research involve?
Participants selected were required to meet the DSM-IV criteria for an "acute state of illness", be in a stable medication status for the duration of the study and have experienced the disease for a minimum for 5 years. Interventions ran over a 4 week period, consisting of 12 session (3 times/week). Participants cognitive performance and specific psychopathological symptoms were tested before and after intervention. They were randomly allocated to 1 of 3 intervention groups: physical exercise and cognitive training, relaxation and cognitive training, and a control group that received no intervention. All interventions were conducted by appropriately trained professionals.

Physical Activity and Cognitive Training

 * 45 minutes of physical activity + 30 minutes of cognitive training
 * Circuit training consisting of a variety of exercise (boxing, ball games etc)
 * Training intensity set at 60-70% of individual's maximum heart rate

Relaxation and Cognitive Training

 * 45 minutes of relaxtion + 30 minutes of cognitive training
 * Exercises including all sensory modalities (breathing exercises, imagery etc)

No Intervention

 * Received no intervention to allow for comparison between intervention types

What were the basic results?
Cognitive training combined with physical activity was found to be a far superior method in managing cognitive deficits associated with MDD and SZ, when compared to the combination of cognitive training and relaxation or medication alone. Both the MDD and SZ groups significantly increased their short-term memory, verbal and visual learning and speed of processing. As well as significant improvements in cognitive performance, patients also significantly reduced their depressive symptoms (MDD) and anxiety (MDD & SZ).

What conclusions should be taken away from this research?
Oertel-Knöchel et al. have shown a combination of physical exercise and cognitive training to be a potential intervention for treating cognitive deficits associated with MDD and SZ. However, further studies in this area are needed and may include an increase in the duration of the intervention, a wide range of physical activities, duration and intensity of sessions, and a larger number of participants to account for a high drop-out rate due to illness.

Practical Advice
While the combination of physical activity and cognitive training shows promising signs of treating cognitive deficits associated with MDD and SZ, it is important to note for the intervention to be effective, it must be used in conjunction with medicinal therapy. Finding the right balance between all treatment types and the appropriate support services is essential in improving an individual's quality of life.