Improving Sleep Continuity Through Mindfulness Training for Better Cognitive Ageing.
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Singapore General Hospital
- Enrollment
- 150
- Locations
- 1
- Primary Endpoint
- Polysomnography: objective changes in sleep onset latency (SOL)
Study Overview
Brief Summary
Poor sleep quality is a known risk factor for cognitive decline in the elderly. Hearteningly, sleep is also a prime target for behavioral modification. In this study, the investigators propose to test mindfulness-based training (MBT) as an intervention to improve sleep quality by reducing sleep fragmentation, and hypothesize that these improvements will mediate the beneficial effects of MBT on sustained and executive attention. MBT consists of a suite of techniques aimed at enhancing awareness and acceptance of one's internal (e.g., thoughts and feelings) and external experiences in the present moment. Learning these techniques has been shown to improve sleep quality in patients with primary insomnia, and in other conditions associated with sleep disturbance. There is also increasing evidence that mindfulness training enhances multiple facets of cognition, including components of attention. In this study, the investigators will recruit 120 participants in a randomized controlled design, with 60 participants receiving MBT, and 60 receiving a sleep hygiene education and exercise program (SHEEP). Each intervention will last 8 weeks. Before and after the intervention, the investigators will collect objective and subjective measures of sleep quality, resting-state and task-related functional magnetic resonance imaging scans, and performance on standard laboratory tests of attention. The investigators hypothesize that, relative to SHE, MBT will result in significantly greater improvements in sleep quality and attentional metrics. They also predict that the cognitive changes will be mediated by the changes in sleep quality. If a positive result is found, this would indicate the use of MBT as a cost-effective behavioral intervention to stabilize or even improve cognition in the elderly, thus reducing the risk of dementia in this vulnerable population.
Detailed Description
Cognitive decline in the elderly is a rapidly growing concern in Singapore and other developed Asian nations. Among the major but understudied factors that may exacerbate this decline is poor sleep quality. Targeting sleep to decelerate or even reverse age-related cognitive decline may represent a low-cost, high-return solution to a widespread societal problem.
To accomplish this goal, the investigators propose to test mindfulness-based training (MBT) as an intervention to improve sleep quality and cognition.
In this pilot grant, the investigators will study a group of participants (N = 120) in a randomized controlled design pitting MBT (N =60) against sleep hygiene education (SHEEP, N = 60).
Hypothesis 1: MBT will lead to significantly greater improvements in sustained and executive attention relative to SHEEP (measured both behaviorally and using functional magnetic resonance imaging).
Hypothesis 2: Cognitive outcomes will be mediated by improvements in subjective and objective sleep quality.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 50 Years to 80 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Adults aged 50 to 80
- •English-speaking
- •Mini-Mental State Examination Score ≥ 26
- •Montreal Cognitive Assessment Score ≥ 23
- •At least one of the following sleep difficulties are expressed:
- •(i) average reported sleep latency of more than 30 minutes
- •(ii) average wakefulness after sleep onset of more than 30 minutes
- •(iii) sleep efficiency or total sleep time of less than 6.5 hours
- •(iv) also a cut off in the PSQI>/=5
Exclusion Criteria
- •Presence of major neurological conditions such as epilepsy, stroke, Parkinson's Disease and/or brain injury
- •Presence of major psychiatric conditions such as major depression or schizophrenia
- •Unsuitability for fMRI scanning (e.g. pacemakers, metallic implants, claustrophobia)
- •Unable to give independent consent or no consent available
Arms & Interventions
Mindfulness Based Therapy for Insomnia
The mindfulness-based intervention consists of eight 2-hour sessions covering various mindfulness techniques (e.g. mindfulness of breath, body and movement, senses and informal practice, and empathy and compassion) that pertain to people with sleep problems and insomnia. Participants will be provided handouts for the information covered during these talks and discussions.
Intervention: Mindfulness Based Therapy for Insomnia (Behavioral)
Sleep Hygiene Education Exercise Program
The Sleep Hygiene Education and Exercise Program has known relationships with good sleep quality. It will comprise of eight weekly 2-hour sessions. Each session will introduce a concept related to sleep and sleep hygiene. The facilitator will provide the theory and rationale behind the concept, and encourage participants to share and discuss their experiences related to the concept. The session will end with the participants evaluating how to implement the specific concept in their daily lives, and its potential implications for their sleep. Participants will be provided with a manual that outlines the concept and how they intend to apply it to their daily lives.
Intervention: Sleep Hygiene Education Exercise Program (Other)
Outcomes
Primary Outcomes
Polysomnography: objective changes in sleep onset latency (SOL)
Time Frame: One night
Polysomnography is a multi-parametric test used in the study of sleep and as a diagnostic tool in sleep medicine. PSG is a comprehensive recording of bio-physiological changes that occur during sleep. It will be performed at night, at the convenience of the participants' home. PSG monitors many body functions including brain, eye movements, muscle activity or skeletal muscle activation and heart rhythm during sleep. The investigators will use a Somnimedics PSG kit. Sleep onset latency reflects the amount of time it takes to participants to fall asleep from the moment they go to bed in the evening, so higher SOL are indicative of poor sleep quality. This objective measure of participants sleep onset latency will judge sleep quality against the subjective measures obtained through the sleep questionnaires.
Change in Cognitive and Attention tasks performance (CANTAB: Stocking of Cambridge)
Time Frame: Up to 10 minutes
Stocking of Cambridge (SOC) assesses spatial planning and requires individuals to use problem-solving strategies to match two sets of stimuli. Primary outcome: number of problems solved on first choice.
Change in Subjective measures of Sleep quality: Pittsburgh Sleep Quality Index Score
Time Frame: Up to one month
Pittsburgh Sleep Quality Index Score (PSQI) is a 19-item self-rated questionnaire for evaluating subjective sleep quality over the previous month. The PSQI has a sensitivity of 89.6% and specificity of 86.5% for identifying cases with sleep disorder, using a cut-off score of 5. The first 4 items are open questions, whereas items 5 to 19 are rated on a 4-point Likert scale. Individual items scores yield 7 components. A total score, ranging from 0 to 21, is obtained by adding the 7 component scores. A score of 5 and above suggests poor sleep quality. A decrease in PSQI score following intervention would reflect and improvement of sleep quality.
Actiwatch: objective changes in sleep onset latency (SOL)
Time Frame: One week
Wrist-worn actigraphy is a convenient and reliable way to monitor sleep. It will be performed using research-grade, wrist-worn accelerometers that are calibrated to detect sleep by inferring from movement patterns. The systems used in this proposal (Philips Respironics AW-2 or Spectrum) has been calibrated against PSG. Sleep onset latency reflects the amount of time it takes to participants to fall asleep from the moment they go to bed in the evening, on average over seven nights of recording. This objective measure of participants sleep onset latency will judge sleep quality against the subjective measures obtained through the sleep questionnaires.
Change in Cognitive and Attention tasks performance (CANTAB: Rapid Visual Information Processing primary outcome)
Time Frame: Up to 10 minutes
Rapid Visual Information Processing (RVP) is a sensitive tool for assessment of sustained attention. Primary outcomes: median response latency. Lower scores in this measure reflect better sustained attention.
Change in Cognitive and Attention tasks performance (CANTAB: Paired Associate Learning)
Time Frame: Up to 10 minutes
Paired Associate Learning (PAL) assesses visual memory and new learning, and is a sensitive tool for accurate assessment of episodic memory. Primary outcome: accuracy on first trials memory score
Change in Cognitive and Attention tasks performance (CANTAB: Spatial Working Memory)
Time Frame: Up to 10 minutes
Spatial Working Memory (SWM) requires retention and manipulation of visuospatial information. This test has notable executive function demands, and measures strategy use as well as errors. Primary outcome: number of errors.
Polysomnography: objective changes in wake after sleep onset (WASO)
Time Frame: One night
In addition to Sleep Onset Latency (Primary outcome 2), a second objective measure of sleep quality is extracted from the polysomnography recording: periods of wakefulness occurring after defined sleep onset. WASO is calculated by taking into account the total time spent in bed, minus sleep latency and minus total sleep time. High WASO scores reflect low sleep continuity and poor sleep quality. This second measure of participants sleep will judge sleep quality against the subjective measures obtained through the sleep questionnaires.
Actiwatch: objective changes in wake after sleep onset (WASO)
Time Frame: One week
As with measures from PSG, in addition to Sleep Onset Latency (Primary outcome 3), a second objective measure of sleep quality is extracted from the Actiwatch recording: periods of wakefulness occurring after defined sleep onset. WASO is calculated by taking into account the total time spent in bed, minus sleep latency and minus total sleep time, averaged over seven consecutive nights. This second measure of participants sleep will judge sleep quality against the subjective measures obtained through the sleep questionnaires.
Change in Subjective measures of Sleep quality: Insomnia Severity Index
Time Frame: Past two weeks
Insomnia Severity Index (ISI) evaluates an individual's level of tendency for insomnia on a 7-item questionnaire, scoring in total from 0 to 28. Scores above 15 indicates moderate severity of clinical insomnia while scores above 22 are indicative of severe clinical insomnia. ISI internal consistency was excellent for population samples both in the community and clinical samples as well, (Cronbach α of 0.90 and 0.91 respectively).
Change in Cognitive and Attention tasks performance (CANTAB: Reaction time task)
Time Frame: Up to 10 minutes
Reaction time task (RTI) provides assays of motor and mental response speeds, as well as measures of movement time, reaction time and response accuracy. Primary outcome: reaction times. Lower reaction times are indicative of better performance.
Secondary Outcomes
- Pen and Pencil cognitive test: IQ Advances Progressive Matrices I and II(Up to 30 minutes)
- Imaging measures (structural): change in orbitofrontal cortex volume(6 minutes)
- Change in functional imaging measures: Breath counting task(10 minutes)
- Behavioral Breath counting task: Accuracy(20 minutes)
- Change in Subjective measures of Sleep quality: Pre-Sleep Arousal,(Past one month)
- Polysomnography: objective changes in total sleep time (TST)(One night)
- Change in oxygen levels during sleep(One night)
- Change in functional imaging measures: Resting state and Inscape(10 minutes)
- Change in functional imaging measures: Letting go practice(10 minutes)
- Change in Cognitive and Attention tasks performance (CANTAB: Emotion Recognition Task)(Up to 10 minutes)
- Change in Cognitive and Attention tasks performance (CANTAB: Verbal Recognition Memory)(Up to 10 minutes)
- Change in Cognitive and Attention tasks performance (CANTAB: Rapid Visual Information Processing)(Up to 10 minutes)
- Behavioral Breath counting task: Errors(20 minutes)
- Pen and Pencil cognitive test: Colour Trails A and B(Up to 30 minutes)
- Five Facet Mindfulness Questionnaire (FFMQ)(Past one month)
- Change in Subjective measures of Sleep quality: Dysfunctional Beliefs and Attitudes about Sleep(Past one month)
- Change in Subjective measures about mood, anxiety and quality of life: Beck's Depression Inventory,(Up to last year)
- Change in Subjective measures about mood, anxiety and quality of life: Short-Form 36(Up to last year)
- Actiwatch: objective changes in total sleep time (TST)(One week)
- Change in Subjective measures about mood, anxiety and quality of life: State Trait Anxiety Inventory(Past year)
- Heart rate during sleep(One night)