Sleep Loss May Increase the Risk of Catching the Flu

NEW YORK -- Every American is at risk for the flu this year, and success in avoiding the viral disease may depend in part on how much they sleep. Research suggests that sleep loss may put you at a higher risk of infection. (1) Additionally, experts advise getting a good night's sleep before getting a flu vaccination since at least one study suggests that sleep loss may temporarily decrease the desired immune response. (2)

"Sleep loss increases an individual's vulnerability to infectious diseases," said Bruce C. Corser, MD, medical director of the Sleep Management Institute in Cincinnati, Ohio. "Even a mild disruption in sleep can reduce the body's immune response and lower your natural resistance against illnesses such as the flu."

Influenza is a highly contagious disease that attacks the respiratory tract. Symptoms may include fever, body aches, fatigue, cough, sore throat, and runny nose. The flu usually affects approximately 10 percent to 20 percent of Americans annually. (3)

According to the Centers for Disease Control and Prevention (CDC), the best protection against the flu is an annual vaccine each fall, given in advance of flu season, which typically begins in November and continues through April. (3) However, research suggests that the efficacy of flu vaccinations may be compromised in the short term in people who do not get adequate sleep. (2)

Research published in the Journal of the American Medical Association reported that sleep deprivation at the time of immunization may limit short- term effectiveness of a flu shot. In the study, flu shots were administered to two groups of healthy men. One group was allowed only four hours of sleep per night for six consecutive nights, and the other group slept normally. On the morning following the fourth night, both groups were vaccinated against the flu. Ten days after their flu shots, those in the sleep-deprived group had less than half the level of flu-fighting antibodies as those in the group that slept normally. (2)

Other studies suggest that sleep deprivation and chronic insomnia are associated with immune alterations. (1,4)

"Clearly, sleep has preventive and recuperative benefits, so it's important to make sleep a priority when trying to maintain overall good health," said Corser.

In surveys, people who classified their insomnia as "serious" were more likely to report multiple health problems,(5) and patients who needed at least two hours to fall asleep nearly every night had greater use of medical services. (6)

Sleep loss is a common problem in America. Sleep experts recommend seven to nine hours of sleep per night for most adults. (7) However, according to a poll sponsored by the National Sleep Foundation, most Americans are not getting the minimum recommended amount of sleep. (8) The poll revealed that approximately two out of five adults (39 percent) reported getting less than seven hours of sleep per night on weeknights. (8)

"Occasional sleep loss is normal," explained Corser. "But if you have persistent problems falling or staying asleep, then you should speak with your doctor about behavioral or lifestyle changes. Likewise, your physician may prescribe sleep medications that can help you fall asleep and increase your total sleep time without next-day grogginess."

Experts suggest that in order to ward off winter viruses and infections, people should pay close attention to their sleep habits. The following are useful, seasonal tips to help Americans improve their sleep and keep their immune systems functioning as best as possible.

* Establish a regular sleep schedule. Go to sleep and wake up at the same

time each day, including weekends. (9) "Use the upcoming clock change

and the bonus hour of nighttime it provides to guarantee yourself a

nine-hour night of sleep," Corser suggested.

* Exercise routinely and complete your exercise well in advance of

bedtime. Regular exercise may enhance the quality of your sleep (10) and

may also offer additional immune system benefits. (11)

* Use a humidifier or place an open bowl of water over a radiator in your

bedroom to keep the air moist. (12) Winter indoor heating can dry out

sinuses, leaving you more susceptible to illness. (12) Likewise, a

bedroom that's too hot or too cold may be uncomfortable and may cause

you to wake up during the night. (13)

* Drink hot chocolate, coffee, or tea to warm up during cold days, but

avoid caffeinated beverages in the late afternoon or evening. (9)

* Use caution when taking over-the-counter medications to treat cold or

flu symptoms. Some of these products contain ingredients that can cause

sleeplessness at night or sleepiness during the day. (14,15)

* If you have trouble sleeping for more than a few weeks, or if sleep

problems interfere with daily performance, speak with your doctor.

Safe, effective prescription sleep medications are available to treat

insomnia.

References:

1. Savard J, Laroche L, Simard S, Ivers H, Morin CM. Chronic insomnia

and immune functioning. Psychosom Med. 2003;65:211-221.

2. Spiegel K, Sheridan JF, Van Cauter E. Effect of sleep deprivation on

response to immunization [letter]. JAMA. 2002;288:1471-1472.

3. Centers for Disease Control and Prevention. Influenza: the disease.

Available at: http://www.cdc.gov/ncidod/diseases/flu/fluinfo.htm.

Accessed June 16, 2003.

4. Ozturk L, Pelin Z, Karadeniz D, Kaynak H, Cakar L, Gozukirmizi E.

Effects of 48 hours sleep deprivation on human immune profile. Sleep

Res Online.1999;2:107-111.

5. Mellinger GD, Balter MB, Uhlenhuth EH. Insomnia and its treatment.

Prevalence and correlates. Arch Gen Psychiatry. 1985;42:225-232.

6. Simon GE, VonKorff M. Prevalence, burden, and treatment of insomnia

in primary care. Am J Psychiatry. 1997;154:1417-1423.

7. National Sleep Foundation. Let sleep work for you! Available at:

http://www.sleepfoundation.org/publications/letsleepwork.html.

Accessed August 8, 2003.

8. National Sleep Foundation. 2002 Sleep in America Poll. March 2002.

Available at:

http://www.sleepfoundation.org/img/2002SleepInAmericaPoll.pdf.

Accessed August 8, 2003.

9. National Sleep Foundation. Before you get your flu shot - get some

sleep. Available at:

http://www.sleepfoundation.org/PressArchives/flushot.html. Accessed

August 7, 2003.

10. Singh NA, Clements KM, Fiatarone MA. A randomized controlled trial of

the effect of exercise on sleep. Sleep. 1997;20:95-101.

11. Nieman DC. Research Digest: Does Exercise Alter Immune Function and

Respiratory Infections? Washington, DC: President's Council on

Physical Fitness and Sports; June 2001.

12. Accent Health. Guide to surviving this cold and flu season. Available

at: http://www.accenthealth.com/viewers/coldflu/. Accessed June 2,

2003.

13. Nordenberg T. Tossing and turning no more: how to get a good night's

sleep. U.S. Food and Drug Administration Web site. Available at:

http://www.fda.gov/fdac/features/1998/498_sleep.html. Accessed August

8, 2003.

14. UC Davis Medical Center. UC Davis Health System. What are drug

treatments for insomnia? Available at:

http://www.ucdmc.ucdavis.edu/ucdhs/health/a-z/27Insomnia/-

doc27drug.html. Accessed August 8, 2003.

15. National Sleep Foundation. Sleep aids: everything you wanted to

know... but were too tired to ask. Available at:

http://www.sleepfoundation.org/publications/sleepaids.html. Accessed

August 8, 2003.

Source: Sanofi-Synthelabo Inc.