Polysomnography (sleep study)

Sleep Apnea is a common but serious sleep disorder characterized by repeated episodes of partial or complete cessation of breathing during sleep, lasting at least 10 seconds and occurring multiple times throughout the night, leading to fragmented sleep, recurrent drops in blood oxygen levels, and significant strain on the cardiovascular and metabolic systems.

There are three main types of sleep apnea. Obstructive Sleep Apnea (OSA) is the most prevalent form, caused by the physical collapse or blockage of the upper airway due to relaxation of the throat muscles during sleep, resulting in snoring, choking, or gasping episodes. Central Sleep Apnea (CSA) occurs when the brain fails to send proper signals to the muscles that control breathing, representing a neurological rather than anatomical problem. Mixed or Complex Sleep Apnea is a combination of both obstructive and central components occurring in the same individual.

Common symptoms include loud and persistent snoring, witnessed breathing pauses during sleep, abrupt awakenings accompanied by choking or gasping, excessive daytime sleepiness and fatigue regardless of the duration of sleep, morning headaches, difficulty concentrating, irritability, and poor memory. Many patients remain undiagnosed for years as the most disruptive symptoms occur during sleep and are often noticed first by a bed partner rather than the patient themselves.

Clinically, sleep apnea is diagnosed through a sleep study known as Polysomnography (PSG), conducted either in a sleep laboratory or via a home sleep apnea test (HSAT). The key diagnostic parameter is the Apnea-Hypopnea Index (AHI), which measures the average number of apnea and hypopnea events per hour of sleep. An AHI of 5 to 14 indicates mild sleep apnea, 15 to 30 indicates moderate sleep apnea, and above 30 indicates severe sleep apnea requiring prompt treatment.

If left untreated, sleep apnea significantly increases the risk of hypertension, coronary artery disease, stroke, cardiac arrhythmias, type 2 diabetes, metabolic syndrome, pulmonary hypertension, and road traffic accidents due to impaired alertness. Treatment options include Continuous Positive Airway Pressure (CPAP) therapy, which is the gold standard and works by delivering a constant stream of pressurized air to keep the airway open during sleep; BiPAP or Auto-PAP devices for patients who cannot tolerate standard CPAP; oral mandibular advancement devices for mild to moderate OSA; positional therapy; surgical interventions such as uvulopalatopharyngoplasty (UPPP) in selected cases; and lifestyle modifications including weight loss, avoidance of alcohol and sedatives, and smoking cessation, all of which play an important supporting role in overall management.