An observational study in Obesity Hypoventilation Syndrome, Obesity and Hypoventilation, sponsored by Istanbul University. Completed at 1 site in Turkey (Türkiye). Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-10-02.
Sponsored by Istanbul University · Observational
Obesity Hypoventilation Syndrome(OHS) is a disease characterized by daytime hypercapnia and sleep-disordered breathing without other causes of hypoventilation in individuals with a body mass index above 30 kg/m2. Sources state that obesity is at the basis of the metabolic changes seen in individuals with OHS. Obesity, together with cardiovascular system complications, lung volumes, work of breathing and sleep quality, creating the basis for respiratory problems. In addition, sedentary lifestyle habits, which are common in obese individuals, cause negative effects on exercise capacity and peripheral muscle strength. It has been shown in the literature that decreased exercise capacity due to obesity strongly interacts with the risk of all-cause mortality. As a result of obesity and all this negative picture, impaired emotional state and decreased quality of life are observed in individuals. Numerous studies have shown that obese individuals generally have a low level of physical activity, there is a decrease in peripheral muscle strength, obese individuals are at risk for sleep-related respiratory problems and health-related quality of life is often negatively affected in obese individuals. With these studies, the effects of obesity on individuals have been evaluated with objective evaluation methods. However, the same cannot be said for OHS. It is not clear how exercise capacity, peripheral muscle strength and quality of life parameters, which are known to be negatively affected by obesity, are affected in individuals with OHS. Based on this point, this study aims to investigate whether OHS has an additional effect on exercise capacity, peripheral muscle strength and quality of life in addition to obesity.
Patients with Obesity Hypoventilation Syndrome who are followed up in Istanbul University, Istanbul Faculty of Medicine, Department of Chest Diseases and obese individuals who are followed up in Istanbul University, Istanbul Faculty of Medicine, Department of Internal Diseases and who are in the low risk group according to stop bang evaluation will be included in the study. The data of individuals diagnosed with OHS and obese individuals will be compared. The study will be conducted in accordance with the Declaration of Helsinki and consent form will be obtained from the patients participating in the study, indicating that they are willing to participate in the study. Before starting the study, the purpose of the study will be explained to the participants and all information about the study will be provided. The subjects who agree to participate in the study will be invited to Istanbul University Faculty of Medicine, Department of Chest Diseases on certain days. Demographic information of the subjects will be recorded. Body composition, presence of comorbidities, exercise capacity, peripheral muscle strength, sleep quality and quality of life will then be assessed. The primary aim of the study was to investigate whether Obesity Hypoventilation Syndrome has an additional effect on exercise capacity, peripheral muscle strength and quality of life compared to obesity.
73 studies on the registry are indexed under Obesity Hypoventilation Syndrome; 10 are open to participants now.
This study's enrollment of 64 is above the median of 50 across 25 observational studies indexed under Obesity Hypoventilation Syndrome.
Browse Obesity Hypoventilation Syndrome studies →Istanbul University is the lead sponsor of 511 studies on the registry; 78 are open to participants now.
Of its 5 completed or terminated interventional studies of FDA-regulated products, 1 (20%) have results posted.
Counted across the registry records on this site, refreshed daily.
Patients with Obesity Hypoventilation Syndrome who are followed up in Istanbul University, Istanbul Faculty of Medicine, Department of Chest Diseases and obese individuals who are followed up in Istanbul University, Istanbul Faculty of Medicine, Department of Internal Diseases and who are in the low risk group according to stop bang evaluation will be included in the study.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Subjects with obesity hypoventilation syndrome (30 \< body mass index \< 45 kg/m2)
Other: Assessment
Age and sex-matched obese subjects (30 \< body mass index \< 45 kg/m2) with low risk of obstructive sleep apnea (STOP-BANG score \< 3)
Other: Assessment
Between December 2023 and June 204, 46 volunteer participants aged 18 years and older who met the inclusion criteria and were followed up at Istanbul University, Istanbul Faculty of Medicine, Department of Chest Diseases and Istanbul Faculty of Medicine, Department of Internal Medicine were included in the project. Participants' body composition, comorbidities, exercise capacity, peripheral muscle strength, sleep quality and quality of life were assessed.
Six Minute Walk Test-Distance
The distance covered in meters in a straight corridor of 30 meters will be recorded as fast as possible but without running for 6 minutes.
Time frame: 1 day
Six Minute Walk Test-Oxygen Saturation
The 6-minute walk test is performed by walking as fast as possible for 6 minutes in a 30-meter corridor. Oxygen saturation measured by pulse oximetry before and after the test is recorded as a percentage.
Time frame: 1 day
Six Minute Walk Test-Heart Rate
The 6-minute walk test is performed by walking as fast as possible for 6 minutes in a 30-meter corridor. The heart rate measured by pulse oximetry is recorded before and after the test.
Time frame: 1 day
Six Minute Walk Test-Blood Pressure
The 6-minute walk test is performed by walking as fast as possible for 6 minutes in a 30-meter corridor. Before and after the test, blood pressure is measured with a sphygmomanometer and recorded in mmHg.
Time frame: 1 day
Six Minute Walk Test-Dyspnea
The 6-minute walk test is performed by walking as fast as possible for 6 minutes in a 30-meter corridor. Before and after the test, a score of 0-10 is recorded according to the Borg scale.
Time frame: 1 day
Six Minute Walk Test-Leg Fatigue
6 dakika yürüme testi, kişinin 30 metrelik bir koridorda 6 dakika boyunca mümkün olabilecek en hızlı şekilde yürümesi ile gerçekleştirilmektedir. Test öncesi ve sonrasında Borg skalasına göre 0-10 arasında puanlandırılarak kaydedilir.
Time frame: 1 day
Nottingham Health Profile
The Nottingham Health Profile (NHP) is a general patient reported outcome measure which seeks to measure subjective health status. It is a questionnaire designed to measure a patient's view of their own health status, in a number of areas. The NHP consists of two parts. The first part focuses on health and comprises 38 items which deal with pain, energy, sleep, mobility, emotional reaction and social isolation. The second part focuses on life areas affected and consists of 7 items which deal with problems regarding occupation, housework, social life, family life, sexual function, hobbies and holidays. The second part of the NHP is optional and can be omitted without ruining the test results.
Time frame: 1 day
Muscle Strength - Dynamometer
A digital dynamometer will be used to evaluate muscle strength. Muscle strength will be evaluated in the following muscles, each measurement will be made three times and the average will be taken.
Time frame: 1 day
Body Fat Percentage
The body fat percentage of a patient is the total mass of fat divided by total body mass, multiplied by 100; body fat includes essential body fat and storage body fat. The body fat percentage of the patients will be evaluated by using the "Tanita BC-545N Body Analysis Scale" with the bioelectrical impedance analysis technique. And results will be recorded in percent.
Time frame: 1 day
Body Fluid Percentage
Body fluids, bodily fluids, or biofluids are liquids within the human body. The body fluid percentage of the patients will be evaluated by using the "Tanita BC-545N Body Analysis Scale" with the bioelectrical impedance analysis technique. And results will be recorded in percent.
Time frame: 1 day
Muscle Mass
Muscle mass refers to the amount of soft muscle tissue in the body. The muscle mass of the patients will be evaluated by using the "Tanita BC-545N Body Analysis Scale" with the bioelectrical impedance analysis technique. And results will be recorded in kg.
Time frame: 1 day
Body Mass Index
Body mass index (BMI) is a value derived from the mass (weight) and height of a person. The BMI is defined as the body mass divided by the square of the body height, and is expressed in units of kg/m2, resulting from mass in kilograms and height in metres.
Time frame: 1 day
Anthropometric Measurements-Neck
With the help of a tape measure, neck circumference will be measured in cm.
Time frame: 1 day
Anthropometric Measurements-Waist
With the help of a tape measure, waist circumference will be measured in cm.
Time frame: 1 day
Anthropometric Measurements-Abdomen
With the help of a tape measure, abdomen circumference will be measured in cm.
Time frame: 1 day
Anthropometric Measurements-Hip
With the help of a tape measure, hip circumference will be measured in cm.
Time frame: 1 day
The Waist-Hip ratio
With the help of a tape measure, waist and hip circumference will be measured in cm. Depending on the circumference measurements, waist and hip circumference is calculated as waist to hip ratio.
Time frame: 1 day
Modified Charlson Comorbidity Index
The Charlson Comorbidity Index (CCI) was initially developed to predict the survival time of individuals diagnosed with cancer by assigning weights to specific diseases. Today, it is used as a guide for individuals with multiple comorbidities. In this index, diseases are scored based on their morbidity and mortality. The total score is calculated by summing the equivalent scores of diseases. Comorbidity classification is categorized as low (score ≤ 3), moderate (score 4 and 5), high (score 6 and 7), and very high comorbidity (score ≥ 8).
Time frame: 1 day
Pittsburgh Sleep Quality Index
The Pittsburgh Sleep Quality Index (PSQI) is a self-report questionnaire that assesses sleep quality over a 1-month time interval. The measure consists of 19 individual items, creating 7 components that produce one global score, and takes 5-10 minutes to complete. Developed by researchers at the University of Pittsburgh, the PSQI is intended to be a standardized sleep questionnaire for clinicians and researchers to use with ease and is used for multiple populations. The questionnaire has been used in many settings, including research and clinical activities, and has been used in the diagnosis of sleep disorders.
Time frame: 1 day
Plan to share: No
No publications or documents are linked to this record.
Ran from Apr 2024 to primary completion in Jan 2025, 8 months.
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This study is completed, as verified in Sep 2025. You cannot join it, but the record below documents what was studied.
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