This is the first post in a two-part series about women and sleep apnea.
The second post, The Health Hazards of Sleep Apnea in Women, looks at the causes and effects of sleep apnea in women.
In this post, we investigate the differences in how women experience and report sleep issues and directly addresses the stereotype that sleep apnea is a man’s disease.
Ask the average physician to describe someone with sleep apnea and they will likely tell you that sufferers of this serious disorder tend to be middle-aged men who are also obese.
However, a large number of patients simply don’t fit that profile. Thanks in part to this stereotype, women with sleep apnea are underdiagnosed and under-treated.
“There is the mistaken notion — not among sleep specialists, but among general practitioners who are the first line of defense — that sleep apnea is a disease of men,” says Said Mostafavi, M.D., the Chief Medical Officer for Advanced Sleep Medicine Services, Inc. and a sleep specialist. “When they see a patient who is a women, they don’t consider it. That is where the diagnosis gets missed.”
Not just middle-aged, obese men who complain of sleepiness
Sleep apnea is a disorder where breathing stops during sleep. There are different kinds, but the most common — obstructive sleep apnea — occurs when the upper airway collapses. The oxygen deprivation and sleep loss that result can lead to serious health complications including stroke, heart disease and even early death.
Much of the research on sleep apnea for the past several decades has focused on men rather than women. In 1999, a group of researchers noted that for every eight men diagnosed with sleep apnea in clinics, there was one woman. However, surveys of the general population— people who did not necessarily seek out a sleep specialist— showed that the true ratio should be closer to one woman with sleep apnea for every two or three men ^1. In other words, a lot of women weren’t getting diagnosed.
Why the discrepancy? There appear to a be a number of factors at work including different biology and symptoms, as well as experts blinded by stereotypes.
“We’ve been trained to identify sleep apnea in middle-aged, obese men who present with sleepiness,” says Dr. Susan Redline, a senior physician at Brigham and Women’s Hospital and the Peter C. Farrell Professor of Sleep Medicine at Harvard Medical School. “We under-recognize sleep apnea in women who are not obese and present with fatigue instead.” She explains that “sleepiness is an inability to stay away and a propensity to doze while fatigue is a sensation more akin to weariness.”
Fortunately, physicians are starting to recognize that women can have sleep apnea too.
A look at the numbers
Finding out how many women have sleep apnea is a challenge: How does one measure people who haven’t been diagnosed? In addition, the exact percentage of women with sleep apnea will vary depending on how researchers measure certain things — such as how many apenas occur in an hour.
However, over the last few decades, experts have come up with some estimates.
A 2008 review of published studies concludes that approximately 3 to 7 percent of adult men have sleep apnea compared to 2 to 5 percent of adult women ^2. Those numbers indicate that more men than women have the disorder, but the seriousness of sleep apnea in women should not be overlooked. Those numbers also change for different groups and different ages. After reaching menopause, for instance, studies show that the risk of women developing sleep apnea jumps to be nearly equal to that of men in same age range ^3.
The estimates are also likely to be lower than the actual prevalence of sleep disordered breathing, cautions Naresh M. Punjabi, the 2008 review’s author. Public awareness of sleep apnea and its health risks could help those numbers better reflect the reality. In the meantime, “the public and personal health care costs globally are likely to be enormous,” Punjabi writes.
The number of American adults with sleep apnea could range from more than 18 million to as much as 25 million. So although the tally of women affected could vary depending on the methods and definitions of sleep apnea used by researchers, it’s clear that hundreds of thousands of women in the U.S. may have sleep apnea. Many may not realize they have sleep apnea and face serious health risks unknowingly. In 1997, Young and his colleagues estimated that as much as 93 percent of women with moderate to severe sleep apnea had not been diagnosed ^4.
Sleep apnea might be different for women
Like Redline mentioned, experts have noted some nuances in the way that women may experience sleep apnea compared to men. Instead of sleepiness, which can be strong enough that men will fall asleep while engaged in another task such as driving, women tend to report fatigue.
“Women may also present with other symptoms that aren’t as common in men with sleep apnea,” Redline says. For example, she says “they may have depression. If physicians aren’t aware of these differences, they they may miss the diagnoses.”
Women may suffer more often from insomnia, inadequate sleep and restless leg syndrome. Doctors that know about the prevalence of those other conditions could mistakenly diagnose their patient with one of those disorders, rather than sleep apnea, even if the person actually has sleep apnea.
Women may also describe their sleep problems differently than men.
Women describe different symptoms
“Men are the textbook definitions of sleep apnea patients,” adds Mostafavi. “They are often overweight, complain of daytime sleepiness and their bed partner complains of snoring. But women are different. They are more vigilant toward their own health and will notice different symptoms that may relate to sleep apnea. Women may come into the doctor’s office not just with daytime sleepiness but with restless leg syndrome or fatigue or insomnia.”
In a 2008 review, Christine Lin from the University of California San Diego School of Medicine and her colleagues reported that men tend to have bed partners and relatives who are concerned about the men’s snoring and those companions push the patients to seek expert evaluation. Women, on the other hand, tend to come to the clinic alone. Whether the women are hiding their troubles from companions or their companions simply aren’t noticing disturbed sleep remains unknown. Lin and her colleagues suggest that snoring may be embarrassing for women and that feeling could keep them from reporting it or confronting it ^5.
Some of the difference between the disorder’s prevalence in men and women has to do with gender-related variation in how fat is distributed throughout the body, the length and collapsibility of the upper airway, hormone response, neuro-chemical control mechanisms among other potential reasons.
Women with the disorder also tend to have less severe sleep apneas. Specifically, they have a lower apnea-hypopnea index and shorter apneas or hypopnea ^6. That variation might translate to a difference in diagnosis rates.
Doctors and clinicians fail to look beyond the stereotype
Yet even with these potential differences, the problem of the stereotype might be the biggest one.
Researchers were already concerned about missing sleep apnea diagnoses in women in in 1996, when researchers at the University of Wisconsin in Madison decided to investigate the problem. They relied on data from 551 men and 388 women who were part of the Wisconsin Sleep Cohort Study. None of the participants had been given a diagnosis of sleep apnea, but the cohort study assessed them through an interview and an overnight sleep study.
Surprisingly, the researchers found that regardless of the severity of sleep apnea, women with the disorder did not report symptoms that were different from those that men reported. Also, for both groups snoring was the most sensitive and strongest indicator of sleep apnea ^1.
The researchers concluded that the reason that fewer women than predicted were receiving a diagnosis of sleep apnea might not actually have to do with a differences in symptoms. Instead they pinned the cause on doctors and clinicians failing to look beyond the stereotype.
“A report of poor quality sleep should really prompt physicians to investigate the basis of the syndrome,” says Redline. “Is it poor sleep hygiene, restless legs or sleep apnea? Snoring and being overweight in particular should stimulate the suspicion for sleep apnea. But with women the absence of sleepiness should not dissuade this concern.”
Missing a diagnosis of sleep apnea could after all, endanger a life.
Are you concerned that you or a loved one may have sleep apnea?
Take the sleepiness quiz.
- Young, T., et al., (1996). The gender bias in sleep apnea diagnosis: Are women missed because they have different symptoms. Arch Intern Med, 156(21), 2445-2451. PubMed
- Punjabi, N.M., (2008). The epidemiology of adult obstructive sleep apnea. Proc Am Thorac Soc, 5(2), 136-143. PubMed
- Tishler, P.V., et al., (2003). Incidence of sleep-disordered breathing in an urban adult population: the relative importance of risk factors in the development of sleep-disordered breathing. JAMA, 289(17), 2230-2237. PubMed
- Young, T., et al., (1997). Estimation of the clinically diagnosed proportion of sleep apnea syndrome in middle-aged men and women. Sleep, 20(9), 705-706. PubMed
- Lin, C.M., et al., (2008). Gender differences in obstructive sleep apnea and treatment implications. Sleep Med Rev, 12(6), 481-496. PubMed
- Ware, J.C., et al., (2000), Influence of sex and age on duration and frequency of sleep apnea events. Sleep, 23(2), 165-170. PubMed
Other posts you may find interesting: