Rotating Night Shift Work and Type 2 Diabetes in Women

A new study found that the longer women worked rotating night shifts, the greater their risk of developing type 2 diabetes. Researchers also found that extended years of rotating night shift work was associated with weight gain. The weight gain may have contributed to the increased risk of type 2 diabetes.

Women who worked rotating night shifts for three to nine years faced a 20 percent increased risk of type 2 diabetes. Women who worked nights for 10 to 19 years had a 40 percent rise in risk. And women who worked night shifts for over 20 years were 58 percent more at risk. Women who worked rotating night shifts also gained more weight and were more likely to become obese during the follow-up.

Rotating night shift work was defined as three or more night shifts plus day and evening hours each month. The Harvard School of Public Health tracked more than 175,000 U.S. nurses for this study. Findings were published Dec. 6 in the journal PLoS Medicine.

Researchers said the findings need to be confirmed in men and ethnic groups (96 percent of the nurses were white Caucasians). The U.S. Centers for Disease Control and Prevention (CDC) estimates that 15 million Americans work full time on evening shifts, night shifts, rotating shifts or other irregular schedules.

Read more about shift work sleep disorder and women’s sleep needs. More stories about sleep and type 2 diabetes are available on the Sleep Education Blog.

Photo by DIAC Images

Did Sleep Medicine Help Boost U.S. Life Expectancy?

Life expectancy hit an all-time high in 2009, according to a new report from the U.S. Centers for Disease Control and Prevention. An American born in 2009 can now expect to live about 78 years and two months, a two month increase compared to 2008. Only 2.4 million Americans died in 2009, an all-time low and the 10th consecutive yearly decrease. As usual, women (80.6 years) had a longer life expectancy than men (75.7 years).

The CDC speculates that vaccinations, public health measures against smoking and better overall medical treatment for the life span improvements. Sleep medicine may be able to share some of the credit.

Deaths from heart disease, Alzheimer’s disease and diabetes – three diseases commonly associated with sleep apnea - all decreased in 2009. This raises the question, is an increase in awareness and treatment of sleep apnea contributing to these rates and helping Americans live longer?

Research shows that people with untreated severe sleep apnea are more than twice as likely to die. Even moderate cases increase the overall risk of death by 17 percent.

Diagnosis and treatment of sleep apnea may prevent countless deaths from heart disease. The pauses in breathing from untreated obstructive sleep apnea can put enormous strain on your heart. Heart disease risks associated with this include coronary heart disease, heart attack and congestive heart failure.

CPAP and other sleep apnea treatments may also slow the development of diabetes. Sleep disorders that disrupt sleep, including but not limited to sleep apnea increases the likelihood of getting diabetes.

Treatment can also limit sleep loss related to sleep apnea, which is a factor in the development of Alzheimer’s disease. CPAP also helps slow the cognitive decline of people with Alzheimer’s.

Think you might have sleep apnea? Find out by scheduling an overnight sleep study for diagnosis. it could save your life in the long run and help.

Note: The average life expectancy in the U.S. is still among the lowest of the developed western nations. The National Research Council reports that the heavy smoking in the past five decades has long figured for the slower growth in life expectancy. The national obesity epidemic is expected to offset the eventual gains from the recent reduction in smoking. Excess body weight a primary risk factor for heart disease and diabetes as well as sleep apnea.

Sleep Disorder Shares Blame for Early Type 2 Diabetes

Type 2 diabetes early in life is commonly associated with obesity, but in many cases there may be another factor at play. Obstructive sleep apnea, a common untreated sleeping disorder in teens, can contribute to the onset of diabetes.

A study in the September issue of SLEEP reports sleep apnea worsens insulin resistance. Insulin resistance is a risk factor for type 2 diabetes as well as metabolic syndrome.

The link between sleep apnea and insulin resistance wasn’t fully clear until now. The presence of obesity and the onset of puberty complicated the relationship.

The study involved a group of 98 obese children of both genders. About half of the participating children had signs of sleep apnea.

Children were recruited from two age groups: pre and post puberty.
Each child was screened for obstructive sleep apnea using an overnight sleep study, and assessed for insulin resistance.

Results show children who tested positive for sleep apnea had worse insulin resistance, thus were at higher risk for type 2 diabetes and metabolic syndrome.

Sleep apnea isn’t the only sleep disorder that can lead to diabetes. A past study shows severe sleep loss from long-term insomnia can also worsen insulin resistance.

Frequent Naps & Type 2 Diabetes in Older Adults

A new study examined the relationship between napping and type 2 diabetes in older Chinese adults. The results were published yesterday in the journal Sleep.

The study involved 19,567 people in China between the ages of 50 and 93 years. About 71 percent of participants were women.

They received a physical exam. They also answered questions about their lifestyle and medical history. This included questions about their napping habits and daytime sleepiness.

Results show that 13.5 percent of the sample had type 2 diabetes. The rate of diabetes was 36 percent higher in people who reported napping four to six times per week. It was 28 percent higher in people who napped daily.

The results were unchanged when people with potential ill health and daytime sleepiness were removed from the analysis. This suggests that it is less likely that diabetes leads to daytime sleepiness. Instead the results raise the possibility that napping may increase the risk of diabetes.

But more research is needed to determine if napping plays a causative role in the development of diabetes. Many other factors may be involved in older adults.

“In many non-Mediterranean, Western countries a large proportion of those that nap are generally older or have other conditions that cause tiredness and create an urge to nap,” lead author Neil Thomas told the AASM. “The napping can therefore be a marker of disease.”

According to the authors, napping is a social norm in China. It is practiced at all ages starting in childhood. At least one nap per week was reported by 67 percent of participants. About 59 percent of these people reported napping daily.

The authors also noted that napping and diabetes were associated even though physical activity levels were higher in nappers. Physical activity has been shown to reduce the risk of diabetes.

Read more about naps and sleep and type 2 diabetes.

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Sleep Apnea & Glucose Control in Type 2 Diabetes

A new study examined obstructive sleep apnea and glucose control in people with type 2 diabetes.

The study involved 60 diabetic adults. They were monitored during an overnight sleep study. Blood samples measured glucose control.

Results show that 77 percent of participants had sleep apnea. And increasing OSA severity was associated with worse glucose control.

"Reducing the severity of OSA may improve glycemic control," lead author Dr. Renee S. Aronsohn said in a press release. "Thus effective treatment of OSA may represent a novel and non-pharmacologic intervention in the management of type 2 diabetes."

Only five people in the study had been previously evaluated for sleep apnea. None were undergoing treatment.

It is estimated that about 80 percent of men and 90 percent of women with moderate to severe sleep apnea are undiagnosed. The most common treatment for sleep apnea is CPAP therapy.

The NIDDK reports that diabetes is a disease in which blood glucose levels are above normal. Most food is broken down into glucose, which is also known as “blood sugar.”

Insulin, a hormone produced by the pancreas, then moves glucose from the blood into the cells. There the glucose becomes a primary source of fuel for the body.

Type 2 diabetes occurs when the body fails to use insulin effectively. This is known as “insulin resistance.” Then the body produces less insulin over time.

As a result glucose builds up in the blood and passes out of the body through urine. This deprives the body of its main fuel source.

Preliminary data indicate that diabetes was the seventh-leading cause of death in the U.S. in 2007. A study published last week estimated that in 2007 diabetes cost the U.S. $218 billion.

On SleepEducation.com you can learn more about how sleep loss and sleep disorders are linked to diabetes. Read more about sleep and type 2 diabetes.

Weight Loss, Sleep Apnea & Diabetes

A new study shows that weight loss may reduce the severity of obstructive sleep apnea in some people who also have type 2 diabetes.

The study involved 264 diabetic adults. They had an average age of 61 years; their mean weight was 226 pounds. They had an average body mass index of 36.7; a BMI of 30 or higher is considered “obese.”

They also had an average apnea-hypopnea index of 23.2. This means that they stopped breathing about 23 times per hour of sleep. An AHI of 15 to 30 is considered “moderate” sleep apnea.

Some participants were assigned to a behavioral weight-loss program; it involved portion-controlled diets and 175 minutes of exercise per week.

Other participants were assigned to a control group; they attended three sessions related to diabetes support and education. The two groups were compared after one year.

Results show that members of the weight-loss group lost an average of 24 pounds. Their average AHI decreased, and they were less likely than controls to have severe sleep apnea at the one-year follow-up. The average AHI increased in the control group.

“These results show that doctors as well as patients can expect a significant improvement in their sleep apnea with weight loss,” lead author Gary Foster said in a Temple University statement. “And a reduction in sleep apnea has a number of benefits for overall health and well-being.”

But about 86 percent of people in the weight-loss group still had sleep apnea at follow-up. The average severity of their OSA remained moderate with an AHI of 18.3, reports MedPage Today.

The AASM recommends dietary weight loss as one treatment strategy for people who are obese and have sleep apnea. But weight loss should be combined with another treatment such as CPAP or an oral appliance.

Read more about weight loss and sleep apnea. In May the Sleep Education Blog reported on another study led by Foster; it found that undiagnosed OSA is common in people with type 2 diabetes.

Get help for sleep apnea at an AASM-accredited sleep center near you.

Image by Chris

Insomnia, Sleep Loss & Diabetes Risk

A new study suggests that people suffering from chronic insomnia and sleep loss may be at risk for type 2 diabetes.

The study involved 1,741 men and women from central Pennsylvania. They were randomly selected for the study. Their sleep was monitored by overnight sleep study in a sleep lab.

Results show that having chronic insomnia for a year or longer was associated with a higher risk for diabetes; the risk was not increased in people with milder insomnia.

The highest risk of diabetes was in people with chronic insomnia who slept for five hours or less; they were almost three times more likely to have diabetes. People with chronic insomnia who slept five to six hours were two times more likely to have diabetes.

The research team also has performed other analyses of this group of people. Their studies have linked chronic insomnia and sleep loss with an increased risk of hypertension; in men they also have found an increased risk of death.

In August the Sleep Education blog reported on the link between sleep loss and diabetes.

Proven treatments for insomnia are available. Both cognitive behavioral therapy and medications are effective.

A board-certified sleep specialist can determine which treatment is best for you. Contact an AASM-accredited sleep disorders center if you have an ongoing problem with insomnia.

Sleep Loss & Type 2 Diabetes Risk

A new study adds to the evidence that links ongoing sleep loss with an increased risk of type 2 diabetes.

The small study involved 11 healthy volunteers; they had a mean age of 39 years. They were slightly overweight with an average body mass index (BMI) of 26.5.

The volunteers spent two, 14-day periods in a sleep lab. The two studies were conducted at least three months apart, reports MedPage Today. During one study period participants spent 8.5 hours in bed each night; during the other two-week study period their nightly time in bed was restricted to only 5.5 hours. In both studies their daytime activities were limited; but they were able to eat as much and as often as they wanted.

Bedtime restriction reduced their nightly sleep duration by more than two hours; during those two weeks they slept for an average of five hours, 11 minutes. Weight gain was similar during both study periods.

Results show that two weeks of sleep loss led to both insulin resistance and impaired glucose tolerance. These are two markers of an increased diabetes risk.

“These results would indicate that a healthy lifestyle should include not only healthy eating habits and adequate amounts of physical activity, but also obtaining a sufficient amount of sleep,” study co-author Dr. Plamen Penev said in a prepared statement.

Another new study used survey data to link sleep duration with diabetes risk in Korean men; the risk of having type 2 diabetes was twice as high in those who reported sleeping five hours or less per night.

A study published in May linked self-reported sleep duration with diabetes risk in whites and Hispanics; those who reported sleeping seven hours or less were twice as likely to develop diabetes.

A 2007 study in the journal Sleep analyzed survey data from almost 9,000 people in the U.S.; sleeping five hours or less increased their diabetes risk by nearly 50 percent.

The AASM reports that most adults need about seven to eight hours of sleep each night. Sleep plays an important role in regulating a number of body functions. These include body temperature, hormone production and metabolism.

Learn more about sleep loss and diabetes on SleepEducation.com.

Diabetes, Sleep Apnea & REM Sleep

A new study in the Journal of Clinical Sleep Medicine links obstructive sleep apnea to type 2 diabetes. It shows that there is an increased risk of diabetes in people who have sleep apnea during rapid eye movement sleep – or “REM sleep.”

The multi-ethnic study involved 1,008 people who were evaluated for sleep apnea; 67 percent were African American, 17 percent were Caucasian and 15 percent were Hispanic. Sleep apnea was diagnosed in 74 percent of participants.

Results show that people with sleep apnea during REM sleep were twice as likely to have type 2 diabetes. The risk of diabetes in middle-aged adults with sleep apnea was increased by almost three times. Overall, 30 percent of the participants with sleep apnea had diabetes.

“Generally, OSA is worse in REM sleep compared to non-REM sleep,” study author Dr. Kamran Mahmood told the AASM. “This may be the reason for closer association of REM-related OSA and type 2 diabetes.”

The study also reports that sleep fragmentation caused by sleep apnea may reduce REM sleep time.

Learn more about sleep apnea and diabetes. Read more about REM sleep and sleep stages on SleepEducation.com.

Get help for sleep apnea at an AASM-accredited sleep center near you.

Undiagnosed Sleep Apnea is Common in People with Diabetes

A new study confirms that undiagnosed obstructive sleep apnea is common in people with type 2 diabetes.

The study involved 306 obese adults with type 2 diabetes. Each participant was monitored during an overnight sleep study.

Results show that almost 87 percent of participants had undiagnosed sleep apnea. Almost 23 percent of participants had severe sleep apnea; they stopped breathing at least 30 times per hour of sleep. Severe sleep apnea was most common in people with a higher body mass index (BMI).

“The high prevalence of undiagnosed, and therefore untreated, sleep apnea among obese patients with diabetes constitutes a serious public health problem,” study author Gary Foster, PhD, said in a Temple University statement.



Diabetes is the sixth-leading cause of death in the U.S. as of 2006. The NIDDK reports that people who are overweight and inactive are more likely to develop type 2 diabetes. Excess weight also is a major risk factor for sleep apnea.

“Doctors who have obese patients with type 2 diabetes need to be aware of the possibility of sleep apnea, even if no symptoms are present,” Foster added.

Diabetes can be treated with insulin and oral medications. CPAP is the most effective treatment for sleep apnea. Diet, exercise and weight loss also can play a role in managing both conditions.

Learn more about sleep apnea, sleep loss and diabetes on SleepEducation.com.