For months, the retired librarian suffered through bouts of drowsiness and reduced consciousness. Eventually, a pulmonologist found that which was masked during treatment for Chronic Obstructive Pulmonary Disease (COPD) was a condition of Obstructive Sleep Apnea (OSA), which was going untreated.
It was only after the 58-year-old patient was put on Bilevel Positive Airway Pressure (BiPAP) therapy — one of the standard treatment protocols for apnea — that his condition dramatically improved.
Or, take the case of a middle aged businessman who was brought by his wife to hospital for excessive snoring. The patient was on oral drugs for diabetes but had elevated blood sugar levels in spite of regular medication. He was borderline hypertensive and slightly overweight.
It was only when pulmonologists conducted an overnight sleep study in the hospital lab, he was diagnosed with Obstructive Sleep Apnea, a potentially serious condition where breathing stops and starts during sleep. The onset of hypertension and deranged blood sugars were a consequence of OSA.
After three months, his wife reported back that the snoring had reduced and the patient was watching TV serials with her without nodding off.
Sleep disorders, and their often serious health consequences, are going undetected or under-reported in the city. However, the good news on this front is that, after remaining low-key, sleep medicine as a specialty is set to get more robust with a new specialised lab coming up in the private sector even as Jipmer prepares to resume sleep studies after an upgrade to its laboratory.
The Department of Pulmonary Medicine in Jipmer, which started a sleep disorder lab in 2011, has done sleep study for more than a hundred patients free of charge. However, it had briefly suspended sleep studies due to the renovation of the facility.
“We will be resuming sleep studies shortly,” said G. Vishnukanth, Associate Professor, Department of Pulmonary Medicine, Jipmer.
“It’s not rocket science for someone to understand that food and sleep are the most important aspects of an individual’s life. What is important to note is that most of the sleep-related problems have an impact, usually adverse, on one’s life. They also tend to have systemic manifestations affecting different parts of the body,” says S. Mathan Raj, consultant pulmonologist who is setting up the first sleep lab in the private sector in the city.
The level 2 polysomnogram equipment (sleep study machine) is being installed at a cost of about ₹5 lakh at Kumaran Hospital.
Sensors are placed on the scalp, face, arms, legs and fingers while the patient sleeps. Brain activity, breathing, oxygen levels and heart rate are measured while the patient sleeps.
80 types
According to pulmonologists, major Western sleep societies have come together and proposed “The International Classification of Sleep Disorders” (ICSD), which as of 2005, stratified more than 80 types of individual sleep disorders, broadly categorised into insomnia, hypersomnia, circadian rhythm disorders, parasomnias, sleep-related breathing disorders and sleep-related movement disorders.
Sleep disorders can have significant consequences on health such as development of cardiovascular diseases, cognitive defects like inability to focus or respiratory failure.
“Obstructive Sleep Apnea is the most common sleep-related breathing disorder. However it remains undiagnosed in a vast majority of patients. With increasing obesity, burden of OSA is expected to rise in the community,” said Dr. Vishnukanth.
When breathing pauses for 10 seconds or more during sleep, it results in sleep apnea. The breathing usually starts with a loud snort or choking sound. These pauses in breathing prevents deep sleep and so the patient feels tired during the day.
In fact, chronic OSA can lead to development of cardiovascular complications like hypertension. Intervention at an earlier stage can slow the progression of the disease.
“OSA occurs in about 10 to 15% of patients with COPD, a condition referred to as the “overlap syndrome”. Although the prevalence of OSA is similar in patients with COPD as in the general population, individuals with both conditions without CPAP treatment have an increased risk of death and more hospitalisation episodes from acute exacerbations,” says Dr. Raj.
Modalities of treatment
There are multiple modalities of treatment. Smoking cessation and weight loss are the first steps. Non-invasive ventilation (NIV) is one modality in which positive pressure is used to overcome airway resistance to allow uninterrupted flow of air — this is the most commonly used method for treatment of OSA.
Medications are also used to treat residual daytime sleepiness when patient is symptomatic despite adequate adherence to NIV. If OSA is due to a structural anomaly in the upper airway which is amenable to surgical correction, surgical management can be done at centres specialised for it.
Oral appliances are also available for structural abnormalities causing sleep apnea.
According to specialists, smoking is a risk factor for both COPD and OSA. Hence OSA and COPD can manifest together. If OSA has been long-standing, then co-morbidities like pulmonary hypertension, systemic hypertension can develop. OSA conditions are also known to complicate interstitial lung disease and bronchiectasis. In fact, OSA can precipitate symptoms in patients with chronic or long standing respiratory diseases, experts said.
Obesity is another major risk factor for development of OSA. Increased thickness of soft tissues around upper airway increases the propensity of airway to collapse during breathing. Moreover, increased chest wall thickness increases the work of respiratory muscles, the respiratory system must overcome a higher resistive load during each breathing cycle. Obesity can also lead to development of a sleep-related breathing disorder called Obesity Hypoventilation Syndrome.
Experts say that sleep-related disorders are most prevalent in adults, and are associated with increased mortality and morbidity from obesity, cardiovascular diseases, diabetes, and depression, resulting in reduced quality of life (QOL) and increased healthcare costs.
According to Abhisekh Chauhan, senior resident, Department of Pulmonology at Jipmer, OSA is now seen as a multisystem disorder. Patients of OSA are to be evaluated by various specialties like neurology, endocrinology, otorhinolaryngology and pulmonary medicine. With the advent of non-invasive ventilator for the management of OSA, majority of the patients are treated by a pulmonologist.
Additionally, medications used to treat COPD, such as albuterol or prednisone may affect sleep quality. A reduction of nocturnal oxygen levels commonly seen in patients with COPD can have profound effects and contribute to long-term sequelae, producing arrhythmias, myocardial stress, and, possibly, lower survival.