A new study conducted in the United States has shed light on the prevalence of a little-known sleep disorder called idiopathic hypersomnia. According to researchers, nearly 5 million Americans, or approximately one in 70 individuals, are affected by this condition, which leads to excessive sleepiness even after a full night's rest. These findings challenge previous estimations that labeled idiopathic hypersomnia as rare, with fewer than 200,000 people believed to be affected.

The study, which surveyed 792 participants and measured their sleep quality using specialized machines, found that 1.5 percent of the participants met the criteria for a diagnosis of idiopathic hypersomnia. In addition, researchers analyzed data collected over a decade on daytime sleepiness, discovering that 10 participants experienced chronic daytime sleepiness, further supporting the notion of the condition being relatively common.

The study also highlighted certain characteristics of those affected by idiopathic hypersomnia. Most participants were found to be obese, with an average age of 59. Additionally, approximately half of the participants were women.

Dr. David Plante, a psychiatrist from the University of Wisconsin-Madison, emphasized the significance of these findings, stating, "Our results demonstrate that idiopathic hypersomnia is relatively common and more prevalent than generally assumed. So, there is likely a sizable difference between the number of people with this disorder and those who seek treatment." Dr. Plante called for increased efforts to identify, diagnose, and treat individuals impaired by idiopathic hypersomnia, suggesting that further research could lead to new treatments and a better understanding of the causes of the condition.

Individuals with idiopathic hypersomnia experience excessive sleepiness throughout the day, despite getting sufficient sleep at night and taking naps. They often struggle to wake up and feel disoriented when they do. Unlike individuals with narcolepsy, those with idiopathic hypersomnia do not feel refreshed after naps or exhibit excessive sleep.

Diagnosing idiopathic hypersomnia is challenging, as there is no single test and it is a diagnosis of exclusion, meaning other conditions must be ruled out. The condition may be caused by hormonal imbalances or disruptions in the body's sleep-wake cycle, known as the circadian rhythm.

Treatment aims to alleviate symptoms and may involve prescribing stimulant medications such as modafinil to help patients stay awake during the day. However, additional research is needed to further comprehend the condition and improve treatment options.

The study, published in the journal Neurology, utilized advanced technology to measure participants' brain waves, blood oxygen levels, heart rate, and breathing rate during sleep. Participants also underwent a daytime nap study, further assessing their sleep patterns. Surveys were conducted to gather data on daytime sleepiness, frequency of napping, and hours of sleep obtained on work and non-work nights.

Dr. Plante emphasized the significance of this research, stating, "It has been difficult to determine the prevalence of idiopathic hypersomnia because expensive and time-consuming sleep testing is required to make a diagnosis. We examined data from a large sleep study and found that this condition is much more common than previous estimates." He compared the prevalence of idiopathic hypersomnia to other common neurologic and psychiatric conditions like epilepsy, bipolar disorder, and schizophrenia.

Additionally, the study's findings highlight the need to raise awareness about idiopathic hypersomnia and provide appropriate support for individuals who may be dealing with this debilitating sleep disorder.