Pickwickian Syndrome

What is Pickwickian Syndrome?

In 1836, the famous English writer Charles Dickens described a condition known as Obesity Hypoventilation Syndrome (OHS) in his book “The Posthumous Papers of the Pickwick Club.” This condition involves a person who is obese (having a body mass index or BMI over 30 kg/m2) struggling to breathe deeply enough while they’re awake, leading to a higher than normal level of carbon dioxide (hypercapnia) in their blood. Importantly, this should not be due to other issues like chronic lung disease or sleep apnea.

Simply put, OHS occurs when a person who is obese cannot breathe in enough oxygen and remove enough carbon dioxide while awake. This situation leads to high amounts of carbon dioxide in the blood (more than 45 mm Hg). The problem is related to both a lower than usual drive to breathe and the physical challenges of breathing with obesity. It’s important to remember that this should happen when there are no other diseases or conditions that could explain the issue. The cause of OHS is tied to a reduction in the brain’s instructions for breathing, a reduced response to high carbon dioxide levels by the breathing system, and a restrictive lung disease pattern.

What Causes Pickwickian Syndrome?

Obesity hypoventilation syndrome (OHS) is a condition that results from decreased breathing drive and capacity due to being overweight or obese. For individuals with a body mass index, or BMI, of more than 30 kg/m2, the extra weight places a burden on the respiratory system and affects the body’s response to carbon dioxide (CO2), leading to a condition known as hypercapnia during the day. Hypercapnia is a situation when there’s too much carbon dioxide (CO2), the body’s main waste product, in your blood.

The development of OHS is due to several factors. Being obese and having a sleep disorder known as obstructive sleep apnea (OSA) are the most common causes. Other factors can include issues with the control of breathing which lead to decreased responses to both low oxygen and high carbon dioxide levels. Doctors usually diagnose OHS only when they have ruled out other possible explanations for reduced breathing capability due to conditions affecting the nerves and muscles, structural problems, or metabolic disorders.

Apnea is defined as a pause in breathing that lasts at least 10 seconds, while hypopnea is a condition where there’s at least a 30% reduction in airflow for 10 seconds, along with at least a 3% drop in oxygen saturation or a disruption in sleep. Both apnea and hypopnea are viewed as comparable events. Although there are several ways to measure irregularities in breathing during sleep, the apnea-hypopnea index (AHI) – a measure of the severity of sleep apnea – is most commonly relied upon.

OHS often co-exists with OSA, defined by an AHI score of 5 or more events per hour. However, not everyone with OHS also has OSA. Around 10% of OHS patients do not present with both conditions, perhaps suggesting separate conditions. Interestingly, the majority, around 70%, of patients with OHS have severe OSA, marked by an AHI score of 30 or more events per hour.

Risk Factors and Frequency for Pickwickian Syndrome

Obesity is a major issue in the United States, affecting more than a third of the population. With the rise in obesity, the number of people suffering from Obesity Hypoventilation Syndrome (OHS) is assumed to be increasing. In fact, 8% of adults are considered severely obese, with a Body Mass Index (BMI) of 40 kg/m2 or above. Extreme obesity, defined as a BMI of over 50 kg/m2, has seen an alarming ten-fold increase from 2000 to 2005 and continues to rise.

OHS is also a common issue among individuals with Obstructive Sleep Apnea (OSA), with an estimated 20% to 30% of people suffering from both conditions. A study found that in hospitalized patients with a BMI of over 35 kg/m2, the prevalence of OHS was 31%. Interestingly, obesity rates vary based on factors like gender, ethnicity, education, and age. Obesity is most prevalent in women, non-Hispanic Black people, those with less formal education, and individuals aged 40 to 59 years. Additionally, OHS tends to occur at lower BMI ranges within the Asian community.

Signs and Symptoms of Pickwickian Syndrome

Obesity hypoventilation syndrome (OHS) often comes to notice when an overweight patient is admitted to an intensive care unit due to acute worsening of chronic inadequate oxygen and excess carbon dioxide levels in the blood, leading to respiratory failure. These patients may need specialised ventilation equipment to help them breathe. They can also be diagnosed by a pulmonologist or sleep specialist during an outpatient visit.

Typically, these patients are quite overweight, with a Body Mass Index (BMI) of over 35kg/m2 and they may report being excessively sleepy during the day. Other symptoms linked with Sleep Apnea, such as snoring, choking at night, witnessed sleep pauses, waking up with a headache, daytime fatigue, poor concentration and memory, and difficulty breathing may also be present.

During a physical examination, the doctor might notice physical characteristics like excess weight, a short and bulky neck, crowded throat or low-positioned uvula (the small dangling flesh at the back of the throat). Signs of right heart failure due to high blood pressure in the lungs (pulmonary hypertension) may also be present. These could include bulging veins in the neck, a louder second heart sound, an enlarged liver, and swelling in the lower legs and feet.

Admission to intensive care unit due to severe respiratory issues
Body Mass Index (BMI) of over 35kg/m2
Excessive sleepiness during the day
Snoring, choking at night, or pauses in breathing during sleep
Waking up with a headache and feeling tired during the day
Poor concentration and memory
Difficulty breathing
Bulging veins in the neck, louder second heart sound, enlarged liver, and swelling in the lower legs and feet

Testing for Pickwickian Syndrome

Obesity hypoventilation syndrome is a condition that often goes undetected until it has progressed significantly. Quick identification is crucial because this condition can lead to serious health complications and risks. If a doctor suspects this condition, they must rule out other health problems before confirming a diagnosis, as the treatment will be based on the precise diagnosis.

Hypercapnia, which is a condition characterized by abnormally elevated levels of carbon dioxide in the blood, can be an early indicator of obesity hypoventilation syndrome. A blood test showing a high bicarbonate level (above 27 mEq/L) can suggest hypercapnia, but it’s not specific and can be caused by other health issues such as vomiting, dehydration, or certain medications. A more conclusive test for this condition involves measuring arterial blood gas, which defines hypercapnia as a carbon dioxide pressure greater than 45 mm Hg in the arteries.

Hypoxemia refers to low levels of oxygen in the blood. It’s not common in individuals with obtrusive sleep apnea (OSA) and is usually confirmed through arterial blood gas demonstrating oxygen partial pressure less than 70 mm Hg. Hypoxia or oxygen deficiency can also be assessed noninvasively using pulse oximetry. The polysomnogram, a type of sleep study, is another valuable tool in evaluating OSA and obesity hypoventilation syndrome.

A complete blood count may be ordered to check for polycythemia, a condition where your body makes too many red blood cells due to chronic hypoventilation and hypoxia. Along with these tests, a doctor might order a chest x-ray, CT scan, or pulmonary function tests (PFT) to rule out other potential causes once hypercapnia is confirmed. These tests measure how well your lungs are working and can reveal problems related to obesity hypoventilation syndrome or rule out other potential causes.

Sleep study with continuous carbon dioxide monitoring at night is considered the gold standard for diagnosing obesity hypoventilation syndrome. The amount of time during sleep spent with oxygen saturation below 90% can also provide a clue towards diagnosing this condition.

Lastly, cardiac studies such as electrocardiogram (ECG) and echocardiogram can be used to check for potential heart problems associated with this disease, such as right heart enlargement and failure due to high blood pressure in the arteries of the lungs, which can occur late in the disease.

Treatment Options for Pickwickian Syndrome

Obesity hypoventilation syndrome (OHS) refers to breathing difficulty during sleep due to obesity. Various treatments have been established to target different mechanisms underlying this syndrome, including treating sleep disorders, promoting weight loss and lifestyle changes, surgical interventions, and medication.

The primary treatment of OHS is using Positive Airway Pressure (PAP) therapy, such as Continuous Positive Airway Pressure (CPAP). PAP therapy works by continuously sending a set level of air pressure, which helps to keep your airways open and reduce breathing problems during sleep. This therapy plays a crucial role and should not be delayed while you’re trying to lose weight. Some people with OHS also need extra oxygen, the need for which should be regularly assessed.

In some cases, a different type of PAP therapy, called BIPAP, might be the first choice. This can happen if your sleep issues involve fewer obstructive events — instances where the airway is blocked or becomes too narrow. Under BIPAP, two levels of pressure are used: one for inhalation and another for exhalation. This helps to eliminate carbon dioxide, a gas that can build up in your blood if you have OHS.

Keeping up with the PAP therapy and using the device correctly is essential but can be challenging. This can be due to issues with the device or the masks, non-compliance, lack of education, or financial constraints. Various types and sizes of masks can be used in patients diagnosed with OHS, making patient education about the disease process and the necessity for PAP treatment crucial.

Oxygen therapy might be necessary for patients with OHS who still have low oxygen levels despite PAP use. However, the use of oxygen alone, without PAP, is discouraged, as it will not augment ventilation and can lead to poor outcomes.

Lifestyle modifications for weight loss are encouraged in all patients with OHS, as it can improve ventilation and reduce risk for complications. A weight loss target of 25% to 30% of actual body weight is usually recommended.

If lifestyle and dietary modifications are not enough, surgical interventions like bariatric surgery might be considered. This is typically recommended when diet, lifestyle changes, and tolerance to PAP therapy is not sufficient. However, the results from these interventions are mixed, and bariatric surgery bears significant risks for OHS patients.

Pharmaceutical therapies for OHS are limited. Some medications, like acetazolamide, medroxyprogesterone, and theophylline, can theoretically increase the body’s response to carbon dioxide buildup or depressed respiratory drive. However, there is limited data supporting their use in practical settings, and such medicines are usually considered the last resort.

Central sleep apnea (CSA) interrupts your regular breathing while you sleep. It’s not the same as Hypoventilation syndrome, because people with CSA usually breathe harder than those with the syndrome. Those who have it will show normal or slightly lower than normal levels of carbon dioxide in their blood.

People with Chronic Obstructive Pulmonary Disease (COPD), especially if they are overweight and have high levels of carbon dioxide in their blood, may often have problems with their breathing during sleep. It’s important to conduct a thorough lung function test and blood tests to diagnose this. If there is evidence of blockage in the airflow, it can’t be diagnosed as OHS.

Certain conditions could result in the lungs not fully expanding, leading to a sharp increase in the level of carbon dioxide in the body. This might be due to problems such as chest wall deformation from diseases like pectus (sunken chest) deformity or spine problems like scoliosis and kyphosis. Having a large fluid-filled stomach (ascites) and severe bowel distension can also affect the lung’s movement by putting pressure on the diaphragm. This restriction often results in poor breathing capability leading to respiratory issues without fully causing respiratory failure.

Neuromuscular diseases may also affect your respiratory system. For instance, Amyotrophic lateral sclerosis (ALS) often leads to a high level of carbon dioxide in your body. Usually, you may experience symptoms like muscle weakness, twitching, and overactive reflexes. Also, issues like spinal cord injuries could affect your breathing during sleep and wakefulness. In many cases, these patients are not typically overweight and have had a previous injury or trauma causing neurological deficits. However, patients with SCI may also have sleep-disordered breathing and difficulty in breathing similar to OHS symptoms.

Muscular dystrophies such as Duchenne or Becker could cause a high level of carbon dioxide in the body but are usually apparent in children due to additional symptoms like muscle weakness, slowed growth, heart problems, and high levels of creatinine kinase in blood tests. Becker muscular dystrophy is slightly more variable and milder but has similar overall symptoms.

Guillain-Barre syndrome typically presents with rapid onset of balanced upper and lower limb paralysis and reduced reflexes over 2 to 4 weeks time frame. This could also result in a disturbance in automatic nerve functions leading to unstable blood pressure or cardiac irregularities.

Myasthenia gravis is known for features like muscle fatigue, double vision, droopy eyelids, difficulty in speaking, limb weakness, and weak cough.

Poliomyelitis and post-polio syndrome could lead to acute limb weakness or fatigue, but these have been typically eradicated in developed countries through vaccination.

Myxedema, a condition caused by extremely low levels of free thyroid hormones, could cause breathing problems and high carbon dioxide levels but will also show symptoms of low body temperature, slow heart rate, slow tendon reflexes. These patients might also have unstable blood pressure along with neurological deficits, and in severe cases could go into a coma.

What to expect with Pickwickian Syndrome

Obesity hypoventilation syndrome, a respiratory condition often found in people with severe obesity, is commonly misdiagnosed. This often leads to frequent hospital visits due to difficulty in controlling carbon dioxide levels in the blood. Over time, this condition can worsen and cause problems with the heart including an increase in blood pressure in the lungs and failure of the right side of the heart, leading to significant health risks and potential death.

Therapy, particularly with a treatment called noninvasive positive airway pressure (PAP), can positively impact patient complications and death rates. However, even with this therapy, people with severe Obesity hypoventilation syndrome are likely to have poorer outcomes compared to those with only Obstructive sleep apnea (OSA), a condition in which breathing stops and starts during sleep. It is also observed that people with Obesity hypoventilation syndrome are often hospitalized, admitted to intensive care units, and experience long-term complications after being discharged from the hospital more than patients only suffering from Obstructive sleep apnea.

Possible Complications When Diagnosed with Pickwickian Syndrome

If obesity hypoventilation syndrome (OHS) is left untreated or continues to worsen, patients often experience conditions such as heart failure, high blood pressure in the lungs, and fluid overload in the body. Patients suffering from OHS generally have a lower quality of life due to multiple symptoms, excessive sleepiness during the day, and higher medical expenses. They also face a higher risk of complications due to increased pressure in the lungs and right side of the heart, which can in turn significantly boost their overall sickness rates and risk of early death compared to those whose sleep disorders aren’t accompanied by excessive carbon dioxide levels (hypercapnia).

A detailed analysis of a study called the Pickwick trial showed that out of 246 participants suffering from OHS, 122 had high blood pressure in the pulmonary artery. In patients with non-severe obstructive sleep apnea, predictors for low pH included high body weight and discrepancies in the peak flow of blood entering and exiting the heart during each heartbeat. Meanwhile, lower oxygen levels when awake and high body mass index were risk factors for low pH in those with severe obstructive sleep apnea coupled with OHS.

Common concerns for individuals with OHS:

Heart failure
High blood pressure in the lungs
Fluid overload in the body
Decreased quality of life
Excessive daytime sleepiness
Increased medical expenses
Increased pressure in the lungs and right side of the heart
Higher overall sickness rate and risk of early death
High blood pressure in the pulmonary artery

Preventing Pickwickian Syndrome

To manage your health condition more effectively, it’s crucial to understand its development and how it links with your sleep patterns. Doctors are there to guide you right from the start, emphasizing the vital role of losing weight and making healthier lifestyle choices. Additionally, they will teach you about the importance of sticking to your prescribed pressurized airway therapy (PAP therapy), and how it can protect you from further health issues in the long run.

Frequently asked questions

The prognosis for Pickwickian Syndrome, also known as Obesity Hypoventilation Syndrome (OHS), can be poor. Without proper treatment, OHS can lead to significant health risks and potential death. Even with therapy, people with severe OHS are likely to have poorer outcomes compared to those with only Obstructive Sleep Apnea (OSA). People with OHS often require hospitalization, admission to intensive care units, and may experience long-term complications after being discharged from the hospital.

Being overweight or obese, having a sleep disorder known as obstructive sleep apnea (OSA), and having issues with the control of breathing are common causes of Pickwickian Syndrome (Obesity Hypoventilation Syndrome).

The signs and symptoms of Pickwickian Syndrome, also known as Obesity Hypoventilation Syndrome (OHS), include: - Admission to the intensive care unit due to severe respiratory issues - Body Mass Index (BMI) of over 35kg/m2 - Excessive sleepiness during the day - Snoring, choking at night, or pauses in breathing during sleep - Waking up with a headache and feeling tired during the day - Poor concentration and memory - Difficulty breathing - Bulging veins in the neck, louder second heart sound, enlarged liver, and swelling in the lower legs and feet These symptoms may be noticed by a pulmonologist or sleep specialist during an outpatient visit or when an overweight patient is admitted to the hospital with acute worsening of chronic inadequate oxygen and excess carbon dioxide levels in the blood, leading to respiratory failure. Physical examination may also reveal physical characteristics such as excess weight, a short and bulky neck, crowded throat, or low-positioned uvula. Additionally, signs of right heart failure due to high blood pressure in the lungs (pulmonary hypertension) may be present, including bulging veins in the neck, a louder second heart sound, an enlarged liver, and swelling in the lower legs and feet.

To properly diagnose Pickwickian Syndrome (obesity hypoventilation syndrome), a doctor may order the following tests: 1. Blood tests: A blood test can measure bicarbonate levels, which can suggest hypercapnia (elevated carbon dioxide levels). Additionally, a complete blood count may be ordered to check for polycythemia (excessive red blood cell production). 2. Arterial blood gas measurement: This test can determine hypercapnia by measuring carbon dioxide pressure in the arteries. 3. Pulse oximetry: This noninvasive test measures oxygen levels in the blood and can help assess hypoxia (oxygen deficiency). 4. Polysomnogram: This sleep study can evaluate both obesity hypoventilation syndrome and obstructive sleep apnea. 5. Chest x-ray, CT scan, or pulmonary function tests (PFT): These tests can rule out other potential causes and assess lung function. 6. Sleep study with continuous carbon dioxide monitoring: This is considered the gold standard for diagnosing obesity hypoventilation syndrome. 7. Cardiac studies: Electrocardiogram (ECG) and echocardiogram can check for potential heart problems associated with the syndrome. It's important to note that the specific tests ordered may vary depending on the individual case and the doctor's clinical judgment.

The doctor needs to rule out the following conditions when diagnosing Pickwickian Syndrome: 1. Chronic lung disease or sleep apnea. 2. Other health problems that could explain the issue, such as vomiting, dehydration, or certain medications. 3. Polycythemia, a condition where the body makes too many red blood cells due to chronic hypoventilation and hypoxia. 4. Other potential causes of respiratory problems, which can be ruled out through chest x-ray, CT scan, or pulmonary function tests (PFT). 5. Central sleep apnea (CSA), which is different from Pickwickian Syndrome and usually shows normal or slightly lower levels of carbon dioxide in the blood. 6. Chronic Obstructive Pulmonary Disease (COPD) with evidence of airflow blockage. 7. Conditions that restrict lung expansion, such as chest wall deformation, spine problems, large fluid-filled stomach (ascites), and severe bowel distension. 8. Neuromuscular diseases like Amyotrophic lateral sclerosis (ALS), spinal cord injuries, and muscular dystrophies. 9. Guillain-Barre syndrome, Myasthenia gravis, Poliomyelitis, and post-polio syndrome. 10. Myxedema, a condition caused by extremely low levels of free thyroid hormones.

The side effects when treating Pickwickian Syndrome, also known as Obesity Hypoventilation Syndrome (OHS), include heart failure, high blood pressure in the lungs, fluid overload in the body, decreased quality of life, excessive daytime sleepiness, increased medical expenses, increased pressure in the lungs and right side of the heart, higher overall sickness rate, and risk of early death. Additionally, high blood pressure in the pulmonary artery is a common concern for individuals with OHS.

A pulmonologist or sleep specialist.

Pickwickian Syndrome, also known as Obesity Hypoventilation Syndrome (OHS), is primarily treated using Positive Airway Pressure (PAP) therapy, such as Continuous Positive Airway Pressure (CPAP). PAP therapy works by continuously sending a set level of air pressure to keep the airways open and reduce breathing problems during sleep. In some cases, a different type of PAP therapy called BIPAP may be used if there are fewer obstructive events. Lifestyle modifications for weight loss are also encouraged, and in some cases, surgical interventions like bariatric surgery may be considered. Pharmaceutical therapies for OHS are limited and usually considered as a last resort.

Pickwickian Syndrome is another name for Obesity Hypoventilation Syndrome (OHS), which was described by Charles Dickens in his book "The Posthumous Papers of the Pickwick Club." It is a condition where a person who is obese struggles to breathe deeply enough while awake, leading to a higher than normal level of carbon dioxide in their blood.

Excessive Daytime Sleepiness Lung Disease & Respiratory Health Obesity Sleep-Disordered Breathing