Researchers

Prevalence of SDB Nocturnal Polysomnography Study Aim
Describe the natural history of sleep-disordered breathing (SDB) across middle and older age with longitudinal polysomnography data on SDB status at multiple timepoints.

Prevalence of SDB Nocturnal Polysomnography Study: What’s involved?
Wisconsin Sleep Cohort Staff conducted in-lab nocturnal polysomnography (NPSG) studies on all Cohort volunteers every 4 years. [1989-2015]

• Takes place in the UW Hospital Sleep Lab (6 pm – 8 am)
• Takes 12-14 hours

Study elements include:

• Health Questionnaires
• Seated Blood Pressure
• Body Habitus: Height, Weight, girth, skinfold
• NPSG
• Cognitive Testing
  • Auditory Verbal Learning Test (AVLT)
  • Grooved Pegboard
  • Trail Making
  • Symbol Digit Modalities Test
  • Oral Word Fluency
  • Digit Cancellation Test
• Supine Brachial Arm / Ankle Blood Pressures
• 12-lead ECG
• Fasting Blood Draw
  • Creatinine, Uric Acid, Potassium, Glucose, C-Reactive Protein
  • Magnesium
  • Lipid Panel (HDL, LDL, Cholesterol, Triglycerides)
  • FSH and LH (Women < 60 years old)
  • Leptin, Ghrelin, TNF-a
  • DNA
• Cephalometry [1989-1991]
• Pulmonary Function Test [1989-2000]
• Rhinometry [1989-1993]

Cardiovascular & Metabolic Outcomes Study Aims

1. Investigate associations of sleep-disordered breathing with early and intermediate markers of cardiovascular dysfunction, damage, and cardiovascular disease.
2. Using longitudinal data, to determine whether chronic or recently acquired SDB is associated with the incidence of the metabolic syndrome and current markers of peripheral and intracranial vascular function.
3. To examine the mutual relation and interaction of SDB and obesity/metabolic syndrome as determinant factors of abnormal vascular function.
4. To determine whether the association between SDB and metabolic syndrome/vascular dysfunction are partially explained by oxidative stress and increased sympathetic activity.

Cardiovascular & Metabolic Outcomes Study: What’s involved?
Wisconsin Sleep Cohort Staff conducted in-lab Cardiovascular and Metabolic Outcome Studies on all Cohort volunteers. [2004-2014]

• Takes place in the UW Hospital Sleep Lab/ UW Atherosclerosis Imaging Lab / UW Veterans Administration Pulmonary Research Lab / UW Imaging Lab (8 am – 4 pm)
• Takes 8 hours

Study elements include:

• Health/ Mood/Activity/Stress Questionnaires
• Seated Blood Pressure
• Body Habitus: height, weight, girth, skinfold
• Echocardiography [2009-2014]
• Arterial Tonometry, Brachial Artery Reactivity, Carotid Intima-Media Thickness, Cerebral Bloodflow [2004-2008]
• Psychomotor Vigilance Test [1995-current]
• Supine Brachial Arm / Ankle Blood Pressures [1993-2008]
• 12 lead ECG [1994-2002, 2009-2014]
• Balance and Gait tasks [2009-current]
• Retinal Photography [2004-2008, 2013]
• Brain Imaging (MRI) [2014-2016]
• Cerebral Blood Flow [2004-2008]
• Urine Analysis [2004-2008]
• Heart Rate Variability [2004-2008]
• Blood Analysis [2004-2008]
  • Creatinine, Uric Acid, Glucose, Insulin, Triglycerides and HDL Cholesterol
  • VEGF
  • DNA

Retirement and Sleep Trajectories (REST) Study

REST Study Aims

1. Investigate whether various sleep disorders affect the age of retirement after adjustment for comorbidities, health behaviors, sleep disorders treatments, and socioeconomic characteristics.
2. Investigate whether retirement is associated with changes in sleep habits, sleep problems or sleep disorders.
3. Investigate whether social resources are associated with sleep problems and sleep disorders and whether social resources moderate the bidirectional association of sleep and retirement.

REST Study: What’s involved?
Wisconsin Sleep Cohort Study mailed surveys to all Cohort volunteers to evaluate sleep and retirement transitions. [2010-2015]

The REST Study:

• Mailed Surveys
• Takes 1-2 hours

Study elements of REST include:

• Survey elements:
  • Occupational Status and Retirement
  • Sleep Habits and Problems
  • General Health and Well-being
  • Activity
  • Social Environment
• Sleep Diary (7-day)

Trajectories of Sleep Patterns as Predictors of Neuroendocrine Dysfunction and Weight Gain Study

Study Aims: Trajectories of Sleep Patterns as Predictors of Neuroendocrine Dysfunction and Weight Gain Study

1. Comprehensively characterize the longitudinal associations of both sleep duration and sleep quality with body habitus trajectories.
2. Determine how the longitudinal associations between sleep parameters and body habitus trajectories characterized above are mediated by several neuroendocrine hormones.

What’s involved? Trajectories of Sleep Patterns as Predictors of Neuroendocrine Dysfunction and Weight Gain Study

New assays of stored samples from Cardiovascular and Metabolic Outcomes Study.  Longitudinal analyses of these already-collected data on sleep and weight trajectories.

Study elements include:

• Repeat of metabolic assays previously performed 1995-2003 on samples acquired after 2003: Leptin, Total Ghrelin, Insulin, High sensitivity C-reactive protein
• New assays on samples collected 1995-2015: Adiponectin, Glucagon-like Peptide 1, Peptide YY, Cortisol.

Midlife Sleep Study

Midlife Sleep Study Aims

1. Measure associations of exposure to unhealthy sleep duration (i.e., too short or too long) and poor sleep quality (e.g., lower sleep efficiency, more frequent arousals, greater sleep time variability) across midlife with cognitive decline and dementia in older age.
2. Measure associations of exposure to unhealthy sleep duration and poor sleep quality across midlife with fall injuries and declines in gait and balance in older age.

Midlife Sleep Study: What’s involved?

Wisconsin Sleep Cohort Staff conducted in-home studies on all Cohort volunteers. [2019-2022]

The Midlife Sleep Study:

• Takes place in the Cohort volunteer’s home (6pm – 9pm)
• Takes 2-3 hours

Study elements of Midlife Sleep Study:

• Balance and Gait tasks [2019-2022, 2009-2014]
  • Timed Up and Go (TUG)
  • Dual Task Method
  • Test of Standing Balance
• Cognitive Testing [2019-2022, 1989-2014]
  • Auditory Verbal Learning Test (AVLT)
  • Grooved Pegboard
  • Trail Making
  • Symbol Digit Modalities Test
  • Oral Word Fluency
  • Digit Cancellation Test
• Grip Strength [2019-2022]
• Psychomotor Vigilance Testing [2019-2022, 1995-2014]
• Vision Testing [2019-2022]
• Questionnaires
  • Balance and Falls
  • Current Physical Activity
  • Hypersomnia Severity Index
  • Health Questionnaire
  • Sleep Inertia
  • Social Environment
  • Sleepiness, Circadian Preference and Depression scales
  • Mood, Life Events and Quality of Life
  • Occupation and Retirement
  • Memory / Dementia Questions
• Sleep Diary (7-day)
• Body Habitus: height, weight, girth

Women’s Sleep Study Aims

Investigate correlates of sleep-disordered breathing in women around the age of menopausal transition.

1. Describe the roles that menopause has in the development and progression of sleep apnea.
2. Describe the roles that menopause has in the development of diminished sleep quality.
3. Describe influences of body composition and hormone replacement therapy on the roles of menopause in aims 1 & 2.

Women’s Sleep Study: What’s involved?

Wisconsin Sleep Cohort Staff conducted in-home study visits every 6 months to a subset of approx. 280 pre- to peri- to post-menopausal Sleep Cohort Study women. [1996-2006]

The Women’s Sleep Study:

• Takes place in the home 1 hour before usual bedtime
• Takes 1-2 hours

Study elements include:

• Health Questionnaire
• Seated Blood Pressure
• Body Measurements: weight and girth (neck, waist and hip)
• In-Home NPSG (Compumedics)

Monthly Flow/Sleep Diary

Disorders of Hypersomnolence Study Aim

Identify hypersomnolence symptoms and their correlates.

Disorders of Hypersomnolence: What’s involved?

Wisconsin Sleep Cohort Staff conducted an in-lab daytime nap study on all Cohort volunteers. [1989-2011]

The Multiple Sleep Latency Test (MSLT) Study:

• Takes place in the UW Hospital Sleep Lab starting the morning after the NPSG or at 9 am – no prior night NPSG
• Takes 8 hours, naps attempted every 2 hours (4-5 attempted naps total)

Study elements include:

• MSLT
• Sleep Log – (7 days prior to MSLT)
• 24-hour Blood Pressure Monitor [1991-2006]

Machine Learning Study Aims

1. Machine Scoring of Sleep Staging
   1. Train deep learning neural networks to automate standard sleep scoring using polysomnograms from Wisconsin Sleep Cohort and Stanford Sleep Cohort.
   2. Compare computer-assisted scoring algorithms with manual scoring.
2. Machine Scoring of Sleep Disordered Breathing
   1. Develop algorithm to detect desaturation and disordered breathing events
   2. Using these detected events, characterize and summarize breathing and oxygenation across time and by sleep stages.

Machine Learning: What’s involved?

Secondary analysis of polysomnograms of Wisconsin Sleep Cohort and Stanford Sleep Cohort.