Yoga and Aerobic Exercise in Psychosis

STUDY OBJECTIVES AND PURPOSE

The present study aims to:

1. Compare the effects of a 12-week integrated yoga therapy and 12-week aerobic exercise program (walking and cycling) on cognitive functions, brain structures and function in female psychosis patients.
2. Compare the changes in physical fitness, clinical symptoms, body-perception, drug adherence, quality of life, and medicational side-effects.

Descriptive data acquired from this study will contribute to a better understanding of the research implications and clinical applications of yoga and aerobic exercise.

SUBJECTS This is a single-blinded, randomized, prospective study using psychopathological assessments, self-rating scales and imaging techniques. In this study, only female psychosis patients will be recruited from the Early Assessment Service for Young People with Psychosis Program (EASY) in Hong Kong, aiming to examine if there is any gender difference in comparison to the study by Pajonk et al. (2007), which selected only male subjects.

Ideally, patients taking Benzodiazepine and anti-depressants will be excluded because of the influence of these drugs on the cognitive test results and hippocampal volume. If it is deemed impractical to completely exclude these patients, all subjects will at least be tried to keep consistent with their antipsychotic dosages, by not permitting more than a 25% change in dose in the first 6 weeks after commencement of the intervention.

According to the data presented in the previous study (F. G. Pajonk et al., 2010), and using the statistical significant level 0.05 and the power 0.80, we calculated the sample size for cognitive assessment is 96 (32 each arm) and for brain imaging the sample required will be 48 (16 each arm) (Noordzij et al., 2010). Considering the drop-out rate will be around 30%, we aim to recruit 120 patients (40 each arm) with half of them (20 each arm) undergoing MRI scanning.

PROCEDURES Subjects will be screened by the clinicians in outpatient units in Hong Kong. They will be asked to sign the consent form when they agree to attend the study. Afterwards, they will be randomly divided into their respective intervention group. Each subject will be given a subject number, which will correspond to the group assignment. There will be two sessions of assessments. In the first session, all 120 subjects will be assessed by an investigator for their cognitive function, severity of symptoms, physical fitness, body-perception, drug adherence, quality of life, and medication side-effects. In the second session, the first 20 subjects recruited into each group will undergo a structural MRI and functional MRI (resting) scan at baseline.

Following the 12-week intervention, the subjects will repeat the same assessments and MRI scan as in the pre-intervention. Patients in waitlist will be provided another 3-month yoga or exercise course according to their willing after the waiting period. All the patients will be followed up for 18 months to assess the long-term effects of both interventions in cognition and symptoms.

For the nature of the study, it is difficult to keep patients blind to group allocation, so that the study can hardly be a double-blinded trial but a single-blinded one. Two investigators will do the yoga training and aerobic exercise without knowing the assessment results. Two research assistants will be well-trained and recruited to do the assessment, and remains blind to treatment allocation.

INTERVENTION PROGRAMS Yoga therapy: The yoga therapy consists of breathing control (10 minutes), body postures (40-45 minutes), and relaxation (5 minutes). The yoga therapy will be carried out three times per week for around 60 minutes at each session. The yoga class will be operated with a size of about 5-10 participants according to the general small-group size with one instructor in the commercial yoga studios in Hong Kong. The body postures used in the present study are designed to cover all body parts to give the body an overall strength and stretching.

Aerobic exercise: The aerobic exercise program will include walking on a treadmill (15-20 minutes), and stationary cycling (25-30 minutes), followed by cool-down stretching afterwards (5 minutes). The aerobic exercise program will also take place three times per week for around 45-55 minutes at each session. The heart rate will be continuously monitored during exercise by a portable recorder aiming to maintain the heart rate in the range of 50-60% of the maximum VO2 value, yielding an exercise exertion level which is considered as a moderate intensity. The aerobic training session will be operated with a size of no more than 10 participants.

Discontiuation: yoga and aerobic exercise will be terminated if the subject reports any uncomfortable symptoms or loses interests in continuing. Discontinuation or non-participation will not affect the usual medical treatment and care, which they receive in the clinical settings.

MEASURES The primary outcomes will be the cognitive tests (memory and attention). Severity of symptoms, physical fitness, and imaging data will be the secondary outcomes. For those patients who drop out during the study will be arranged to an additional assessment session at the withdrawal according to the willingness of the participants. Data of these drop-out patients will be used in the final analysis with the intention-to-treat (ITT) method.

All measurements will be taken at baseline, 12 weeks (upon completion of intervention program) and at 18 months for all 120 subjects. MRI will be carried out at baseline and at 12 weeks for the first 60 subjects recruited.

1. Cognitive Functioning
2. Wechsler Adult Intelligence Scale (WAIS): The current study uses Information sub-test and Digit-Symbol-Coding sub-test.
3. Hong Kong List Learning Test (HKLLT): is a validated Chinese list-learning test (Chan et al., 2000). It provides assessments of the processes and organizational strategies involved in verbal learning.
4. Digit Span Test: is a subtest of the Wechsler Adult Intelligence Scale-Revised. (Wechsler, 1981) It includes digit-span forwards (DF) and digit-span backwards (DB) tests.
5. Letter Cancellation Test: subjects are asked to cancel the letter C and E as quickly as possible. Time, number of error and omission items will be recorded (Lezak, Howieson, \& Loring, 1995).
6. Stroop Color and Word Test: Assessment of cognitive flexibility, resistance to interference from outside stimuli, and the ability to suppress a prepotent verbal response. (Stroop, 1935) 5. Subjective Cognitive Impairment Scale (SCIS): A 31-item self-reported questionnaire designed to assess the subjective daily life cognitive impairments in patients with schizophrenia.

II. Magnetic Resonance Imaging (MRI) The first 20 subjects recruited into each group will be scanned using a 3T scanner (Philips Achieva 3-Tesla Quasar). A T1-weighted, MPRAGE sequence (TE=3.2ms, TR=7.5ms, flip angle=7°, FOV 240mm×240 mm) of 155 consecutive slices will be acquired at sagittal view with a voxel size of 1mm×1mm×1 mm. A T2*-weighted EPI sequence will be used for functional magnetic resonance (fMRI) resting (TR/TE=2000/32ms, 32 slices) with a voxel size of 3x3x4mm.

III. Physical Fitness:

1. VO2 max (oxygen consumption): is the maximum capacity of an individual's body to transport and utilize oxygen during incremental exercise, which reflects the physical fitness of the individual.
2. Body Mass Index (BMI).
3. Dual-energy X-Ray Absorptiometry (DXA): assesses the body composition and bone density by passing a very low-level x-ray signal through the body.
4. Sit-and-Reach test: is a common measure of flexibility, and specifically measures the flexibility of the lower back and hamstring muscles.
5. Standing Balance Test: ask the person to stand on one foot for as long as possible. The test will be conducted with the person having their arms on their waist. Repeat the test on the other leg.
6. Star Excursion Balance Test (SEBT) (Olmsted, Carcia, Hertel, \& Shultz, 2002): The SEBT is performed with the subject standing at the center of a grid placed on the floor, with 8 lines extending at 45。 increment from the center of the grid. The subject is asked to maintain a single-leg stance while reaching with the contralateral leg (reach leg) as far as possible along the appropriate vector. The distance from the center of the grid to the touch point is measured in centimeters.

IV. Clinical Assessment

1. Positive and Negative Syndrome Scale (PANSS).
2. Calgary Depression Scale (CDS).
3. Quality of Life The Short Form (36) Health Survey (SF-36).

VI. Body-perception and Drug adherence measure

1. Figure Rating Scale (FRS): there are seven male/female contour drawings, numbered "1" to "7", in increasing body size from left to right. Subjects are asked to choose one figure drawing that most accurately represents the size of their own bodies and then one that represents their desired figure.
2. Cognitive Attitude towards Body Size: subjects are asked whether they think they are: 1) underweight; 2) of normal weight; or 3) overweight.
3. Compliance Rating Scale (CRS): is used to assess medication adherence.
4. Drug Attitude Inventory (DAI-30): assesses the subjects' attitude to the current medication they are taking.

VII. Adverse event No current studies reported any physical or mental artifacts of yoga and aerobic exercise. There is some inherent potential risk of injury in any kind of physical activity. All exercises, both yoga and aerobic exercise, will be increased in a progressive manner to minimize this risk.

The adverse event of the antipsychotics will be assessed by UKU, which is a new comprehensive rating scale for psychotropic drugs and a cross-sectional study of side effects in neuroleptic-treated patients.

STATISTICS The Statistical Package for Social Sciences version 17.0 (SPSS 17.0 statistical package) will be used for the data analysis. Primary outcome variables will be cognition (Hong Kong List Learning Test), and structural imaging data (hippocampal and cingulate cortex volume).

A mixed effects model of repeated measure will be used to compare the changes in cognition and clinical symptoms among the three groups. With mixed effects model, all available data of each subject at each time point will be used (R. Gueorguieva \& J. H. Krystal, 2004). This strategy was based on the assumption that data were missing at random (Ralitza Gueorguieva \& John H Krystal, 2004).With the unstructured covariance structure (Joe et al., 2009), differences between the three intervention groups over time were assessed with a Group x Time interaction term. Primary outcome measures (HKLLT, Digit Span test, Letter Cancellation test) will be first analyzed by including all three groups. For analyses meeting this criterion of statistical significance, follow-up, the priori comparisons of the active intervention groups with the waitlist group were carried out with the same strategy. All tests will be based on two-sided probabilities set at a significance level of 0.05. The Bonferroni correction procedure will be conducted to adjust for the multiple comparisons among groups.The effect size (Cohen's d) will be calculated as well to compare the therapeutic effects of yoga and aerobic exercise among the three groups.

Image processing and analysis will be carried out with the software packages FSL4.1, Freesurfer 5.1 and SPM8. The primary outcomes of structural MRI data will be the changes of grey matter in hippocampus and prefrontal cortex. The primary outcomes of functional MRI data will be the activity changes in prefrontal cortex and cingulate cortex.