Sleepiness and the Risk of Falling

Study Overview
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Brief Summary
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The purpose of this project is to examine the impact of sleeping pills and waking up in the middle of the night on walking balance and cognitive function, to identify risk factors for falls in older adults. A significant percentage of falls, approximately 33 to 52 percent, occur during the nighttime and morning hours when people are normally sleeping; therefore, it is possible that sleep and sleeping medication related impairments in balance may contribute to this risk.

Detailed Description
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Awakening from sleep is well documented to impair cognitive performance in young adults. This phenomenon, called sleep inertia, has been reported to impair performance just as much as one night of total sleep deprivation, suggesting that there are significant functional consequences to sleep inertia. However, whether walking stability is impaired by sleep inertia is unknown. If sleep inertia impairs walking stability, it could be an important but currently unrecognized risk factor for falls in older adults. Also, the impact of aging on sleep inertia-related impairments in cognitive performance is unknown. Sleeping medication use is higher in older than younger adults, and is a risk factor for falls. Current evidence suggests that sleeping medications impair walking stability and cognitive performance in young and older adults during wakefulness; however, no study has examined walking stability and cognitive performance of young and older adults upon awakening from sleep at night after taking a hypnotic (sleeping medication). Therefore, the purpose of this study is to determine whether sleep inertia and hypnotic use impairs walking stability and cognitive performance more in healthy older than in healthy younger adults. It is expected that findings from the proposed study will provide evidence for sleep inertia as a risk factor for falls in older adults. Twelve older (aged 60-85) and twelve younger (aged 18-35) healthy male and female volunteers will participate in the study. The investigational procedures will include medical screening (e.g., physical, blood and urine tests, and bone mineral density assessment), home monitoring of sleep schedules for three weeks, and three overnight visits in the laboratory spaced approximately one week apart. During the laboratory visits, participants will be awakened in the middle of the night to perform walking stability and cognitive function tests. Before going to bed, participants will take either a placebo pill or a sleeping medication. On one of the visits, participants will be asked to go to bed about 2 hours later than usual.

Official Title
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Aging, Hypnotics, Sleep Inertia and the Risk of Falling

Conditions
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Aging, Balance, Sleep

Intervention / Treatment
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* Drug: zolpidem


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Males and females Aged 18 to 35, or 60 to 85 Lived at Denver altitude or higher for at least one year Stable treated diseases: thyroid dysfunction (including hypothyroidism and hyperthyroidism), hypertension, hypercholesterolemia, urinary incontinence, prostate enlargement, gastroesophageal reflux disease, irritable bowel syndrome Exclusion Criteria: Aged 36 to 59, under 18, or over 85 BMI less than 18.6 or greater than 30 kg/m2, women below 95 pounds regardless of BMI Sleep duration is less than 5 or more than 9 hours Sensitivity to sleeping medications Night work in the preceding 6 months Transmeridian travel (across more than 2 time zones) in the last 1 month Bone mineral density DXA T-score of less than -1.75 Orthostatic intolerance Prior history of falls in past year Prior history of injurious fall in past 5 years Hip fracture following a fall Difficulty rising from a sitting position without use of hands to push off Needing to walk slowly or with a wide base of support to maintain balance Hormone replacement therapy for less than 3 months Connective Tissue and Joint Disorders Neurologic Disorders Musculoskeletal Disorders Immune Disorders Sleep Disorders Chronobiologic Disorders Cardiovascular Disorders Respiratory Disorders Kidney and Urinary Tract Disorders Infectious Diseases Gastrointestinal Disorders Hematopoietic Disorders Neoplastic Diseases Endocrine and Metabolic Diseases Psychopathology Dementia Drug dependency

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: zolpidem|nan|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in gait stability: normal walking and beam walking across force plates (platforms with sensors that measure the force (energy) that occurs when the foot contacts the ground during walking) |  |  | 
| at 1, 15, and 30 minutes after awakening in the middle of the night during all three visits |  |  | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in gait stability: normal walking and beam walking across force plates at 1, 15, and 30 minutes after awakening in the morning during all three visits. |  |  | 
| cognitive performance: computerized assessment of executive function at 5, 20, and 35 minutes after awakening in the middle of the night and in the morning during all three visits. |  |  | 
| sleep architecture: visual scoring of the sleep EEG across 8 hours of scheduled sleep during all three visits. |  |  | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Performance, Gait stability, sedative, hypnotic, quality of life, sleep disorder, wakefulness, sleeping pills, Cognitive function