
Obesity hypoventilation syndrome (OHS) is a condition in which obese people may not get enough oxygen during the day or the night, resulting in excessive sleepiness during the day among other problems. This is due to sleep disordered breathing or sleep apnea possibly related to excess weight leading to respiratory problems. OHS is diagnosed when there is no other explanation for any breathing related abnormality and obesity is a factor. It causes low oxygen levels in the blood leading to multiple physical problems when left untreated.
It is also known as Pickwickian syndrome, named after the character of ‘Joe’ in The Posthumous Papers of the Pickwick Club by Charles Dickens. Joe is highly obese and has the tendency to fall into deep sleep at any time during the day. The actual discovery of the syndrome was done by authors of a report about a poker player who became obese and later used to get tired and sleepy during the day and fall asleep.
What Are The Symptoms Of OHS?
How would you know that you have obesity hypoventilation syndrome? Studies show that it is a disorder that is often misdiagnosed or under diagnosed by medical professionals, so it is important to know the symptoms and then ask the doctor if you possibly may have it. Clinical obesity is the obvious commonality. Other symptoms may range from mild to severe and it is not necessary that all would be present at the same time. The signs to look out for include:
- Increased day time sleepiness
- Poor night sleep
- Sleep apnea or sleep disordered breathing
- Memory problems
- Difficulty in concentration
- Irritability
- Headaches
- Mood swings
- Snoring
- Difficulty in exercising
- Depression
When you don’t get restful sleep in the night it leads to many physical and psychological problems. You cannot function well during the day and this impacts all areas of your daily activities. With obesity hypoventilation syndrome present, there can be even more serious consequences.
What Kinds Of Serious Consequences?
OHS needs to be treated otherwise it has a cascading and negative effect on your life. OHS can result in less oxygen being carried in the blood and because the carbon dioxide-oxygen exchange is compromised, the level of carbon dioxide in the blood rises. This leads to further complications. So if you suspect OHS you need diagnosis and treatment. Some of the consequences of physical problems are:
- Lack of oxygen leads to strain on the heart
- Congestive heart failure
- Angina
- High blood pressure
- Pulmonary hypertension (in the lungs)
- Leg edema
Both heart problems and stoppage of breathing can potentially be fatal. People suffering from obesity hypoventilation syndrome often land up in hospital.
How Is OHS Diagnosed?

An example of a wrist oximeter
There are a number of tests that a doctor may advise to check whether you actually have obesity hypoventilation syndrome or not. That is because many disorders may present similar symptoms and the physician also needs to rule out any physical problems that may have the same symptoms. Some of the tests may include
- Arterial blood gas test – this will indicate the presence of carbon dioxide in the blood and the level of oxygen.
- Polysomnography – this will show whether there are sleep disturbances, hypoventilation or hypoxia when sleeping.
- Oximetry in the night – this will show the presence (or absence) of sleep apnea.
- Chest X-ray – to check for any heart related problems.
- ECG – to check for arrhythmias or blockages, including right ventricular problems.
- Lung function tests – to check the flow of air into and out of the lungs.
- FBC (also called CBC) – (Full Blood Count or Complete Blood Count) a blood test to measure different parameters in the blood, including a check for anemia.
- TFT– (Thyroid Function Test) a blood test that will indicate if you have underactive thyroid that can have similar symptoms.
Apart from advising different tests, the doctor will also take your medical history and check your BMI to see your obesity levels.
Can Obesity Hypoventilation Syndrome Be Treated?
It is important to treat the underlying cause of OHS. The primary one here is overweight. So, while diet and exercise may be first line of treatment for weight reduction, if you have been unsuccessful then your doctor may recommend bariatric surgery so that you do lose weight successfully. Often weight loss alone will improve OHS significantly and you may not need any other treatment.
Other treatment options include breathing support by way of external devices. PAP or positive airway pressure involves the use of a machine to regulate breathing. This uses air pressure to keep the airways open so that the levels of oxygen and carbon dioxide in the blood are normalized. Two different machines may be used: CPAP or continuous positive airway pressure that consists of a mask that is placed over the nose and mouth to help with breathing. The other machine is BiPAP or bilevel positive airway pressure that reduces and increases the pressure as you breathe in and out. The devices are compact and easy to use and come in different sizes and with varied functions.
For severe cases of OHS that may need hospitalization, ventilator support is the first line of support. In emergency cases, a tracheostomy may be necessary so that you get the oxygen you need. Medicines (especially sedatives) are generally not advised as they can depress the breathing. As yet there are no recommended oral medicines for this condition, but your doctor may want to change any existing medicines that you are taking to achieve better outcomes.
If you are obese and suffer from sleeping problems it is best to get a definitive diagnosis from a medical professional. You should get all the required tests and then go in for the treatment required to manage or treat the condition so that you can avoid other long term serious health problems.
Whether it is weight loss or the use of devices to help sleep disordered breathing or sleep apnea your compliance is extremely important if you want to lead a long and healthy life.
And that concludes our writeup on obesity hypoventilation syndrome. If you found this to be helpful, please share and/or leave a comment below!
–Josh