Polysomnography (Sleep Study): Your Comprehensive Guide to Diagnosing Sleep Disorders in India

In today's fast-paced world, the importance of a good night's sleep often takes a backseat. Yet, sleep is a fundamental pillar of our health, crucial for physical restoration, mental clarity, and emotional well-being. When sleep eludes us, or is constantly interrupted, it can have profound impacts on every aspect of our lives, from daily productivity to long-term health. Across India, there's a growing recognition of sleep-related health issues, with conditions like insomnia, sleep apnea, and narcolepsy becoming more prevalent. This increased awareness underscores the critical role of accurate diagnostic tools. Among these, Polysomnography, commonly known as a sleep study, stands out as the gold standard for comprehensively evaluating and diagnosing a wide spectrum of sleep disorders.

If you or a loved one are struggling with persistent sleep problems, understanding Polysomnography is the first step towards finding answers and effective treatment. This guide will walk you through what a sleep study entails, why it's performed, how to prepare, what happens during the procedure, how to interpret the results, and what to expect regarding costs in India.

What is Polysomnography (Sleep Study)?

Polysomnography (PSG) is a non-invasive, comprehensive diagnostic test designed to record various physiological parameters while you sleep. Think of it as an overnight health check for your sleep. The term "polysomnography" literally means "many sleep measurements." During a PSG, specialized sensors are used to monitor brain activity, eye movements, muscle tone, heart rate, breathing patterns, blood oxygen levels, and body position, all simultaneously. This rich tapestry of data allows sleep specialists to construct a detailed picture of your sleep architecture and identify any underlying disturbances.

The test is crucial because many sleep disorders manifest only during sleep, making them difficult to diagnose through a standard physical examination or daytime consultation alone. By capturing a full night's sleep, PSG provides objective evidence of sleep disruptions, allowing for precise diagnosis and personalized treatment plans. In India, as sleep clinics and specialists become more accessible, PSG is becoming an indispensable tool in the fight against sleep-related health issues, helping millions move towards healthier, more restorative sleep.

Why is Polysomnography (Sleep Study) Performed?

The primary purpose of a polysomnography is to meticulously monitor and record various physiological parameters during sleep to diagnose and characterize a wide array of sleep disorders. With the rising prevalence of sleep problems in India, PSG has emerged as the definitive diagnostic test for a multitude of conditions. Here's a detailed look at why a sleep study might be recommended:

• Diagnosing Sleep-Related Breathing Disorders: This is one of the most common reasons for a PSG.

  • Obstructive Sleep Apnea (OSA): PSG is the most accurate method to diagnose OSA, a condition where the airway repeatedly collapses or narrows during sleep, leading to pauses in breathing. The study measures the frequency and duration of these episodes (apneas) and partial obstructions (hypopneas), along with associated drops in blood oxygen levels and sleep fragmentation.
  • Central Sleep Apnea (CSA): Unlike OSA, CSA occurs when the brain fails to send proper signals to the muscles that control breathing. PSG helps differentiate between OSA and CSA by monitoring respiratory effort alongside airflow.
  • Sleep-Related Hypoventilation/Hypoxia: These conditions involve consistently shallow breathing or chronically low oxygen levels during sleep, often associated with lung diseases (like COPD) or neuromuscular disorders. PSG accurately quantifies the extent of oxygen desaturation and assesses ventilation.

• Identifying Non-Respiratory Sleep Disorders: PSG extends beyond breathing issues to uncover other complex sleep conditions.

  • Insomnia: While often diagnosed clinically, PSG can be helpful in cases of suspected paradoxical insomnia (where individuals perceive they are sleeping much less than they actually are) or when other sleep disorders are suspected to be contributing to chronic sleeplessness. It helps objectively quantify sleep onset latency, wake after sleep onset, and total sleep time.
  • Narcolepsy: This chronic neurological condition causes overwhelming daytime sleepiness and sudden attacks of sleep. PSG, often followed by a Multiple Sleep Latency Test (MSLT) the next day, helps diagnose narcolepsy by revealing abnormalities in sleep architecture, such as early onset of REM sleep.
  • Restless Legs Syndrome (RLS) and Periodic Limb Movement Disorder (PLMD): RLS is characterized by an irresistible urge to move the legs, often accompanied by uncomfortable sensations. PLMD involves repetitive limb movements during sleep. PSG monitors leg movements and helps quantify their frequency and impact on sleep quality.
  • REM Sleep Behavior Disorder (RBD): This parasomnia involves acting out dreams during REM sleep due to a lack of normal muscle paralysis. PSG monitors muscle activity during REM sleep to detect these abnormal movements.
  • Parasomnias (other types): While not all parasomnias (like sleepwalking or night terrors) require PSG for diagnosis, it can be useful in complex cases or to rule out other underlying sleep disorders. The video recording feature is particularly helpful here.

• Assessing the Effectiveness of Existing Treatments: For patients already diagnosed with a sleep disorder, PSG can be used to evaluate how well their current treatment is working. For instance, a titration study (a type of PSG) is performed to determine the optimal pressure settings for Continuous Positive Airway Pressure (CPAP) therapy in OSA patients.

• Monitoring Conditions Affecting Sleep: Individuals with chronic heart or lung diseases, neurological conditions, or certain psychiatric disorders often experience secondary sleep disturbances. PSG can help monitor how these conditions impact sleep quality and identify specific sleep disorders that may worsen their primary health issues.

• Investigating Unexplained Symptoms: If you experience persistent, unexplained symptoms such as excessive daytime sleepiness, chronic fatigue, morning headaches, difficulty staying asleep despite sufficient opportunity, or loud, disruptive snoring, a sleep specialist may recommend a PSG to uncover the root cause. It provides objective data that can confirm or rule out a sleep disorder, guiding further investigation and treatment.

In essence, Polysomnography offers a comprehensive and objective window into your sleep, providing the detailed information necessary for an accurate diagnosis and the development of a tailored treatment plan that can significantly improve your quality of life.

Preparation for Polysomnography (Sleep Study)

Proper preparation is key to ensuring accurate and reliable results from your polysomnography. While the procedure itself is non-invasive, a few simple steps can make a significant difference. Your doctor or the sleep center staff will provide specific instructions, but here's a general guide to help you prepare:

• Inform Your Doctor About Medications and Medical History: This is perhaps the most crucial step.

  • Full Medical History: Provide a comprehensive overview of your medical history, including any chronic conditions, recent illnesses, or surgeries.
  • Current Medications: Disclose all medications you are currently taking, including prescription drugs, over-the-counter medicines, herbal supplements, and vitamins. Some medications, particularly sedatives, stimulants, or certain antidepressants, can influence sleep patterns and alter PSG results. Your doctor will advise if any medications need to be adjusted or temporarily stopped before the test. Never stop or alter your medication without consulting your doctor.
  • Recent Changes: Inform your doctor about any recent changes in your health or sleep patterns.

• Avoid Stimulants and Depressants:

  • Caffeine: Refrain from consuming caffeine (coffee, tea, soft drinks, energy drinks, chocolate) for at least 24 hours before your sleep study. Caffeine is a stimulant that can interfere with your ability to fall asleep and disrupt your normal sleep architecture.
  • Alcohol: Avoid alcohol for at least 24-48 hours prior to the test. Alcohol acts as a sedative initially but can lead to fragmented sleep, worsen sleep apnea, and suppress REM sleep, thus skewing the results.
  • Heavy Meals: Avoid heavy, spicy, or fatty meals close to bedtime on the day of the test, as they can cause indigestion and disrupt sleep.

• Maintain Your Normal Sleep Schedule: In the days leading up to the test, try to stick to your usual bedtime and wake-up routine as much as possible. Avoid napping, especially if you usually don't. The goal is to capture your typical sleep patterns, so deviating from your routine can affect the accuracy of the study.

• Personal Hygiene and Skin/Hair Preparation:

  • Shower/Bathe: Take a shower or bath before arriving at the sleep center. Clean skin allows for better adhesion of the electrodes and sensors.
  • Hair: Wash your hair thoroughly and ensure it's clean and dry. Avoid using any hair products such as oils, gels, sprays, conditioners, or heavy creams on the day of the test. These products can create a barrier, making it difficult for the electrodes to stick to your scalp and potentially interfering with brain wave readings.
  • Skin: Avoid applying lotions, moisturizers, perfumes, or makeup to your face, neck, and chest, as these can also interfere with sensor adhesion.

• What to Bring for an In-Lab Study:

  • Comfortable Sleepwear: Pack comfortable pajamas or nightwear that you would normally wear to sleep.
  • Personal Toiletries: Bring your toothbrush, toothpaste, comb, and any other personal hygiene items you use.
  • Medications: Bring any essential medications you need to take at night or in the morning.
  • Reading Material/Entertainment: If you need something to help you unwind before bed, bring a book or magazine. Avoid electronic devices close to bedtime.
  • Comfort Items: If you have a specific pillow or blanket that helps you sleep, you may bring it, though most sleep centers provide comfortable bedding.

• Arrival at the Sleep Center: For in-lab studies, you will typically need to arrive at the hospital or sleep center in the late afternoon or early evening. This allows sufficient time for admission procedures, paperwork, and the careful placement of all the sensors by a trained sleep technologist before your usual bedtime. Be prepared for this setup process to take some time, usually between 45 minutes to an hour.

By following these preparation guidelines, you contribute significantly to the quality and accuracy of your polysomnography, paving the way for a more precise diagnosis and effective treatment plan.

The Polysomnography (Sleep Study) Procedure

The polysomnography procedure is designed to be as comfortable and unobtrusive as possible, allowing for a natural night's sleep while comprehensive data is collected. It's typically an overnight examination conducted in a specialized sleep center or a hospital sleep lab. However, for certain conditions, home sleep tests (HSTs) are also an option.

In-Lab Polysomnography (Level 1 Sleep Study)

Considered the gold standard, an in-lab polysomnography offers the most comprehensive assessment. Here's what you can expect:

1. Arrival and Setup:

   • You'll arrive at the sleep center in the evening, usually a few hours before your typical bedtime.
   • You'll be shown to a private room, designed to mimic a comfortable bedroom, complete with a bed, a bedside table, and sometimes a private bathroom. The room is quiet, dark, and temperature-controlled to promote natural sleep.
   • A trained sleep technologist will greet you and explain the procedure in detail, answering any questions you may have.
   • The technologist will then begin the process of attaching various sensors to your body. This is a meticulous but painless process. The sensors are non-invasive and secured with a gentle adhesive or tape. While the number of wires might seem daunting at first, they are designed to be flexible and allow for movement during sleep.

2. Sensors and What They Monitor: The technologist will carefully place a series of sensors on specific parts of your body, each designed to capture different physiological data:

   • Brain Wave Patterns (Electroencephalogram - EEG): Small electrodes are placed on your scalp. These electrodes record your brain's electrical activity, which is crucial for identifying different sleep stages:

     • Wakefulness: Before you fall asleep and during any awakenings.
     • Non-Rapid Eye Movement (NREM) Sleep: Divided into three stages (N1, N2, N3). N1 is light sleep, N2 is deeper sleep, and N3 (slow-wave sleep or deep sleep) is the most restorative stage.
     • Rapid Eye Movement (REM) Sleep: The stage where most dreaming occurs, characterized by brain activity similar to wakefulness but with muscle paralysis. EEG helps diagnose conditions like narcolepsy (by detecting early REM onset) and REM sleep behavior disorder (by monitoring brain activity during REM).

   • Eye Movements (Electrooculogram - EOG): Electrodes are placed near your eyes. These track eye movements, which are particularly important for identifying REM sleep, characterized by rapid eye movements. They also help distinguish between wakefulness and different sleep stages.

   • Muscle Tone/Activity (Electromyogram - EMG):

     • Chin Electrodes: Placed on the chin, these monitor muscle relaxation, which is a hallmark of REM sleep. Abnormal chin EMG readings can indicate muscle tension during REM, suggesting conditions like REM sleep behavior disorder.
     • Leg Electrodes: Placed on the legs, these detect periodic limb movements (repetitive, involuntary leg jerks), which are characteristic of Periodic Limb Movement Disorder (PLMD) and can disrupt sleep.

   • Heart Rate (Electrocardiogram - ECG): Electrodes placed on your chest monitor your heart's electrical activity. This helps detect any changes in heart rate, rhythm disturbances (arrhythmias), or other cardiac events that might occur during sleep, which can be associated with sleep apnea or other sleep disorders.

   • Breathing Patterns and Airflow:

     • Nasal Cannula: A small tube placed under your nose measures airflow through your nostrils and mouth, detecting cessations (apneas) or reductions (hypopneas) in breathing.
     • Effort Sensors: Elastic belts placed around your chest and abdomen measure the effort your body makes to breathe. This helps differentiate between obstructive (effort but no airflow) and central (no effort, no airflow) apneas.
     • Snore Microphone: A small microphone detects snoring, providing objective evidence of its presence and severity.

   • Blood Oxygen Levels (Pulse Oximetry): A small, painless clip placed on your finger or earlobe continuously measures the oxygen saturation in your blood (SpO2). Drops in oxygen levels (desaturations) are a key indicator of sleep-related breathing disorders like sleep apnea.

   • Body Position Sensor: A small sensor records your sleeping position (back, side, stomach), as some sleep disorders, particularly OSA, can be position-dependent.

   • Audio and Video Recording: A low-light, infrared video camera and an audio system are used to observe your sleep. This allows the technologist to visually confirm events like snoring, body movements, restless legs, or parasomnias (e.g., sleepwalking, talking in sleep) that might not be fully captured by other sensors. It also enables the technologist to communicate with you if needed.

3. During the Night:

   • Once all sensors are attached, you'll be encouraged to go to sleep as you normally would. The technologist will be in a separate monitoring room, observing your data on a computer screen throughout the night.
   • If you need to use the restroom, the technologist can temporarily disconnect some wires to allow you to get up, and then reattach them.
   • The goal is to capture at least 6-7 hours of your sleep.

Home Sleep Tests (HSTs - Level 2 or 3)

For patients with a high suspicion of Obstructive Sleep Apnea (OSA) and no significant co-existing medical conditions, a Home Sleep Test might be recommended. These are simpler, more convenient, and more affordable than in-lab PSGs.

• Procedure: You receive a portable device from the sleep center, along with instructions on how to attach a limited number of sensors (typically a nasal cannula, effort belts, and a pulse oximeter) yourself before going to bed at home. You return the device the next day for data analysis.
• What They Measure: HSTs primarily focus on parameters essential for diagnosing OSA: airflow, breathing effort, heart rate, and blood oxygen levels.
• Advantages: Greater comfort, convenience, and lower cost.
• Limitations: Less comprehensive than in-lab PSG. They do not typically measure brain waves, eye movements, or detailed limb activity, meaning they cannot diagnose conditions like narcolepsy, PLMD, or complex insomnias. They also lack direct supervision by a technologist.

Split-Night Study

Sometimes, if severe OSA is detected early in an in-lab PSG, the night may be "split." The first half is used for diagnosis, and if OSA is confirmed, the second half is used for CPAP titration, where a CPAP machine is introduced, and different pressure settings are tested to find the optimal level to keep the airway open. This saves the patient from needing a separate night for CPAP titration.

Regardless of the type of study, the procedure is designed to gather comprehensive data about your sleep, providing the crucial insights needed for an accurate diagnosis and effective management of your sleep disorder.

Understanding Results

Once your overnight sleep study is complete, the journey towards understanding your sleep health truly begins. The collected data undergoes a rigorous evaluation process to pinpoint any underlying sleep disorders.

1. Data Evaluation by a Technologist: Immediately after the study, a trained sleep technologist manually reviews the vast amount of recorded data. This involves "scoring" the sleep study, which means meticulously charting:

   • Sleep Stages: Identifying periods of wakefulness, NREM (N1, N2, N3), and REM sleep, as well as the transitions between them.
   • Sleep Events: Marking every occurrence of apneas, hypopneas, respiratory effort-related arousals (RERAs), limb movements, arousals (brief awakenings), and oxygen desaturations. This detailed scoring creates a comprehensive log of your sleep architecture and any disruptive events throughout the night.

2. Interpretation by a Sleep Specialist: The scored data is then reviewed and interpreted by a certified sleep specialist or a physician with expertise in sleep medicine. In India, the Indian Society for Sleep Research (ISSR) emphasizes that a certified sleep specialist or a physician meeting specific interpretation standards should sign the sleep report after thoroughly reviewing the raw data and the technologist's scoring. This expert interpretation is crucial for an accurate diagnosis and treatment plan.

   Key aspects of result interpretation include:

   • Sleep Architecture Analysis:

     • Sleep Onset Latency: How long it took you to fall asleep.
     • REM Latency: How long it took you to enter your first REM sleep cycle. A very short REM latency can be indicative of narcolepsy.
     • Total Sleep Time (TST): The actual amount of time you spent asleep.
     • Sleep Efficiency: The percentage of time spent in bed that you were actually asleep.
     • Proportion of Sleep Stages: The percentage of time spent in N1, N2, N3 (deep sleep), and REM sleep. Abnormal percentages (e.g., reduced deep sleep, fragmented REM) can indicate various sleep disorders or poor sleep quality.
     • Sleep Fragmentation: How often your sleep was interrupted by arousals or awakenings, which can severely impact restorative sleep.

   • Respiratory Event Analysis:

     • Apnea-Hypopnea Index (AHI): This is one of the most critical metrics for diagnosing sleep apnea. It quantifies the average number of apneas (complete cessation of breathing for at least 10 seconds) and hypopneas (significant reduction in airflow, often accompanied by a drop in oxygen or an arousal) per hour of sleep.
       • Normal: AHI < 5 events per hour
       • Mild OSA: AHI 5-15 events per hour
       • Moderate OSA: AHI 15-30 events per hour
       • Severe OSA: AHI > 30 events per hour
     • Respiratory Effort Related Arousals (RERAs): These are sequences of increasing respiratory effort leading to an arousal from sleep, but not meeting the criteria for apnea or hypopnea. They contribute to sleep fragmentation and daytime sleepiness.
     • Central vs. Obstructive Apneas: The sleep specialist differentiates between these two types based on the presence or absence of respiratory effort during a breathing pause.

   • Oxygenation Data:

     • Lowest SpO2 (Oxygen Saturation): The lowest percentage of oxygen in your blood recorded during the night. Values below 90% are generally considered significant and indicative of hypoxemia (low blood oxygen).
     • Oxygen Desaturation Index (ODI): The number of times per hour your blood oxygen level drops by a certain percentage (e.g., 3-4%) from baseline. A high ODI signifies recurrent oxygen deprivation.
     • Cumulative Time Below 90% SpO2: The total duration your blood oxygen remained below a critical threshold.

   • Cardiac Data:

     • Heart Rate Variability: Changes in heart rate during respiratory events.
     • Arrhythmias: Detection of any abnormal heart rhythms during sleep.

   • Limb Movement Analysis:

     • Periodic Limb Movement Index (PLMI): The number of periodic limb movements per hour of sleep. A high PLMI can indicate Periodic Limb Movement Disorder (PLMD), especially if associated with arousals.

   • Body Position Data: Analysis of whether respiratory events are more severe or frequent in certain sleep positions (e.g., on the back).

   The comprehensive interpretation of these metrics allows the sleep specialist to:

   • Confirm or rule out suspected sleep disorders.
   • Determine the severity of the diagnosed disorder.
   • Understand the underlying pathophysiology.
   • Formulate a personalized treatment plan, which might include lifestyle modifications, CPAP therapy, oral appliances, surgery, or medication.

Risks Associated with Polysomnography

Polysomnography is a remarkably safe procedure with minimal risks. It is non-invasive and generally painless. The most common minor inconveniences or risks include:

• Skin Irritation: Mild irritation, redness, or a slight rash from the adhesive used to attach the electrodes. This typically resolves quickly.
• Difficulty Sleeping: Some patients might find it challenging to fall asleep or sleep normally in an unfamiliar environment with sensors attached. While this can happen, sleep technologists are skilled at making patients comfortable, and the test is designed to capture data even during partial sleep.
• Anxiety: Anxiety about being observed or performing well on the test can sometimes occur. The sleep team aims to create a reassuring environment to minimize this.

Factors that can potentially influence PSG results include the patient's comfort level in the testing environment, certain medications (which is why disclosure is crucial), and, very rarely, equipment inaccuracies. It's also important to note that a single night's study may not capture all possible findings, especially for intermittent conditions. However, the comprehensive nature of PSG makes it the most reliable diagnostic tool available.

Costs in India

The cost of a polysomnography (sleep study) in India can vary significantly, reflecting differences in the type of study, the healthcare facility (government vs. private), its location, and the expertise of the sleep specialists involved. Understanding these variations is crucial for patients considering the test.

• In-Lab Polysomnography (Level 1): This is the most comprehensive and expensive type of sleep study, performed in a specialized sleep lab with continuous technologist supervision.

  • Private Hospitals: In major metropolitan cities like Delhi, Mumbai, Bangalore, and Hyderabad, the cost typically ranges from INR 10,000 to INR 25,000. Premium, multi-specialty hospitals or dedicated sleep centers might charge upwards of INR 25,000, sometimes even reaching INR 30,000 to INR 35,000.
  • Smaller Cities/Tier-2 Cities: In cities like Chennai, Pune, Ahmedabad, or Kolkata, the costs might be slightly lower, generally ranging from INR 8,000 to INR 18,000.
  • Government Hospitals: Public sector hospitals and medical colleges often offer polysomnography at significantly subsidized rates or even for free, though wait times can be longer.

• Home Sleep Tests (HSTs - Level 2 or 3): These are generally more affordable and convenient, primarily used for suspected Obstructive Sleep Apnea.

  • Level 3 (Unattended HST): This basic test measures limited parameters (airflow, effort, oximetry). Costs typically range from INR 2,000 to INR 7,000. This is often the most economical option.
  • Level 2 (Attended HST or more comprehensive unattended HST): These may include more sensors or sometimes involve a technologist setting up the equipment at the patient's home. Costs can range from INR 6,000 to INR 12,000.
  • Rental Options: Some providers offer rental of HST devices, which can further reduce the upfront cost.

• Split-Night Study: If a split-night study is performed (diagnosis and CPAP titration in one night), the cost is often comparable to a full in-lab PSG, as it still requires extensive technologist involvement and comprehensive monitoring.

• Multiple Sleep Latency Test (MSLT): This daytime test, used specifically to diagnose narcolepsy and objectively measure daytime sleepiness, is typically performed on the day following an in-lab PSG. It involves multiple nap opportunities throughout the day. The cost for an MSLT is usually additional to the PSG and can range from INR 5,000 to INR 10,000.

• Factors Influencing Cost:

  • Location: Major metropolitan areas generally have higher costs.
  • Facility Type: Private hospitals and specialized sleep clinics are more expensive than government institutions.
  • Technology and Equipment: Centers with advanced, state-of-the-art equipment may have higher charges.
  • Expertise of Sleep Specialist: The fees for interpretation by highly experienced or renowned sleep specialists might also contribute to the overall cost.
  • Pre-procedure Tests/Consultations: Any consultations or preliminary tests required before the PSG might incur additional charges.

• Insurance Coverage in India: As of the current time, most health insurance plans in India do not explicitly cover the cost of a sleep study. This means that for many patients, it remains largely an out-of-pocket expense. However, this trend is slowly changing, and it's always advisable to check with your specific insurance provider about their policy regarding diagnostic sleep studies, especially if it's deemed medically necessary by a specialist. Advocacy for better insurance coverage for sleep diagnostics is ongoing in India.

Given the significant costs, patients are encouraged to discuss all options with their healthcare provider, understand the necessity of the test, and inquire about the total estimated expense before proceeding.

How Ayu Helps

Ayu simplifies your healthcare journey by allowing you to securely store and access all your medical records, including your Polysomnography reports, in one place. It also helps you find and book appointments with certified sleep specialists, making it easier to manage your sleep health needs.

FAQ (Frequently Asked Questions)

1. Is Polysomnography a painful procedure? No, Polysomnography is a completely non-invasive and painless procedure. The sensors are attached to your skin with adhesive or tape, and while there are many wires, they are flexible and do not cause discomfort.

2. Can I sleep normally with all the sensors attached? Many patients worry about this, but most people manage to sleep enough for a diagnostic study. The sleep technologists are skilled at making you comfortable, and the rooms are designed to promote natural sleep. While you might not sleep exactly as you do at home, the data collected is usually sufficient for diagnosis.

3. How long does it take to get the results after the sleep study? Typically, it takes about 7-10 working days to receive your sleep study report. This includes the time for the sleep technologist to score the data and for the sleep specialist to interpret it thoroughly and prepare a comprehensive report.

4. What happens if I don't sleep much during the study? Even if you don't feel like you slept well, the sleep study can still provide valuable information. It records wakefulness, and even partial sleep can reveal significant diagnostic clues, especially regarding breathing events and limb movements. If insufficient data is collected, your specialist will discuss options, which might include a repeat study.

5. Is the cost of a sleep study covered by health insurance in India? Currently, most health insurance plans in India do not explicitly cover the cost of a sleep study, meaning it is largely an out-of-pocket expense for patients. However, it's always advisable to contact your specific insurance provider to confirm their current policy.

6. What happens after I receive my sleep study results? Once you have your results, you will have a follow-up consultation with your sleep specialist. They will explain the findings, provide a diagnosis, discuss the severity of any identified sleep disorder, and recommend a personalized treatment plan based on your specific needs.

7. Can I take my regular medications on the day of the sleep study? You should always inform your doctor about all medications you are taking. They will advise you if any need to be adjusted or temporarily stopped before the test. Do not stop any medication without consulting your doctor.

8. What is the difference between an in-lab Polysomnography and a Home Sleep Test (HST)? An in-lab PSG (Level 1) is conducted in a sleep center, is supervised by a technologist, and monitors a comprehensive set of parameters including brain waves, eye movements, and muscle activity, providing a detailed picture of sleep architecture. An HST (Level 2 or 3) is performed at home, is unsupervised, and measures a more limited set of parameters (primarily breathing, oxygen, and heart rate), making it suitable mainly for diagnosing suspected Obstructive Sleep Apnea in uncomplicated cases.