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Completed

NCT Number: NCT04108819

Ketogenic Diet for Obesity Hypoventilation Syndrome

Obesity hypoventilation syndrome (OHS) is a condition that occurs in small percentage of obese people that causes high carbon dioxide and low oxygen levels in the blood. OHS is associated with respiratory failure, pulmonary hypertension, and death. The cause of OHS is unclear. Since not all obese people develop OHS, it is believed that hormone imbalances can contribute to the breathing problem.

Some diets can change the body's hormones. For example, low-carbohydrate, high fat "ketogenic" diets (KD) may decrease insulin and glucose levels and increase sensitivity to other hormones. The investigators hypothesize that a KD will improve breathing in OHS patients, even in the absence of weight loss.

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Key information

About this study

Obesity hypoventilation syndrome (OHS) is a condition that occurs in small percentage of obese people, that leads to high carbon dioxide levels and low oxygen levels in the blood. OHS is associated with respiratory failure, pulmonary hypertension, hospital admissions, and death. Unfortunately, there is no treatment for OHS besides massive weight loss which often requires bariatric surgery.

In this study, the investigators are examining whether switching from a regular diet to a ketogenic diet will improve breathing, oxygen, and carbon dioxide levels in OHS patients. After a few days-weeks on KD, hormone changes are known to occur and the investigators are examining whether these hormonal changes could stimulate breathing.

This is a pilot study to examine the effects of a 12 day KD on OHS. The outcomes of the study include blood oxygen, carbon dioxide levels, plasma levels of hormones such as insulin, leptin, sleep studies, body composition a, weight, and metabolic rate.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Obesity (BMI≥30 kg/m2)
  • Hypercapnia (PaCO2>45 or PvCO2>50) on blood gas, OR a sleep study with end-tidal/transcutaneous CO2 monitoring showing an awake CO2 level >50
  • Participants without blood gas data may also have suspected OHS on the basis of serum bicarbonate >=28 mEq/L
  • Lack of an alternative pulmonary diagnosis that adequately explains hypercapnia. Note that a documented pulmonary diagnosis (e.g. chronic obstructive pulmonary disease (COPD) or asthma) per se will not necessarily exclude subjects, since OHS is often misdiagnosed as obstructive lung disease. Functional or radiographic data must corroborate the presence of the alternate diagnosis.
  • Subjects must have had a sleep study and clinical evaluation for sleep apnea. Most subjects with OHS are expected to have concomitant obstructive sleep apnea (OSA). This information is necessary to determine whether continuous positive airway pressure (CPAP)/noninvasive ventilation (NIV) will be used on the research sleep studies.

Exclusion criteria

  • Concomitant participation in another weight loss or diet program
  • Patients with diabetes taking Sodium-glucose Cotransporter-2 (SGLT2) inhibitors (due to risk of diabetic ketoacidosis)
  • Patients with type 1 diabetes
  • Any patients with a history of diabetic ketoacidosis
  • Patients with incomplete sleep apnea diagnosis or management (i.e. those still acclimating to CPAP, or pending therapeutic decisions about OSA management)
  • Known or suspected abuse of narcotics or alcohol
  • Liver cirrhosis
  • Uncontrolled gout
  • History of chronic renal insufficiency requiring dialysis
  • Females who are pregnant, breast-feeding, or intending to become pregnant
  • Food allergies or diet restrictions that research nutritionists cannot accommodate

FOLLOW THIS LINK TO SEE IF YOU QUALIFY:

https://mrprcbcw.hosts.jhmi.edu/redcap/surveys/?s=RYX7DELK9Y

Treatment and study plan

Ketogenic diet

Dietary Supplement

Subjects will undergo ketogenic diet at a 2.5:1 (fat: carb + protein) ratio for a 2-week period.

Primary outcomes

  1. Change in Awake venous carbon dioxide (PvCO2) Level

    Time frame: Baseline (pre keto diet) and 2 weeks post keto diet

    Measured in mmHg.

Secondary outcomes

  1. Change in Venous pH

    Time frame: Once per week, over 4 weeks

    Measured in moles per liter.

  2. Change in Glucose level

    Time frame: Once per week, over 4 weeks

    Measured in g/dL.

  3. Change in Insulin level

    Time frame: Once per week, over 4 weeks

    Measured in mIU/L.

  4. Change in leptin level

    Time frame: Once per week, over 4 weeks

    Measured in ng/mL.

  5. Change in beta-Hydroxybutyrate level

    Time frame: Once per week, over 4 weeks

    Measured in mg/dL.

  6. Glucose profile

    Time frame: Continuously measured over 4 weeks

    Using continuous glucose monitoring (CGM), to measured glucose level (g/dL) each day at home.

  7. Change in Body weight (kg)

    Time frame: Once per week, over 4 weeks

  8. Change in Oxygen saturation

    Time frame: Once per week, over 4 weeks

    Measured as a percentage.

  9. Change in Blood Pressure

    Time frame: Once per week, over 4 weeks

    Measured in mmHg.

  10. Change in percentage of body fat

    Time frame: Once every 2 weeks, over 4 weeks

    The investigators will measure percentage body fat using the Bioelectrical impedance analysis (BIA).

  11. Change in Apnea Hypopnea Index

    Time frame: Once every 2 weeks, over 4 weeks

    The apnea hypopnea index (AHI) is derived from combined information from EEG signals, flow sensors, respiratory belts, and carbon dioxide censors and is a measure of severity of sleep apnea. AHI < 5 is considered normal. AHI 5-15 is considered mild sleep apnea. AHI 15-30 is considered moderate sleep apnea. AHI >30 is considered severe sleep apnea.

  12. Change in LDL Cholesterol

    Time frame: Once per week, over 4 weeks

    Measured in mg/dL.

  13. Change in HDL Cholesterol

    Time frame: Once per week, over 4 weeks

    Measured in mg/dL.

  14. Change in Triglyceride level

    Time frame: Once per week, over 4 weeks

    Measured in mg/dL.

Sponsors and collaborators

Lead sponsor

Johns Hopkins University

Other

Registry information

Acronym: KETOHS

Important dates

Study start
2019
Primary completion
2022
Study completion
2022
First posted
Sep 30, 2019
Registry last updated
Jul 1, 2022

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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