Sleep apnea is one of the most common and most underdiagnosed sleep disorders in the world. An estimated 30 million Americans have obstructive sleep apnea — yet up to 80% remain undiagnosed. Many people live for years or even decades with untreated sleep apnea, attributing their symptoms to stress, aging, or simply not being "a good sleeper," unaware of the serious health consequences building quietly in the background.