TUESDAY, Jan. 8 (HealthDay News) -- Improved diet, more exercise and the diabetes medication metformin can help people suffering with schizophrenia control the weight gain that typically accompanies their medications, a Chinese study suggests.
Three months of both medication and lifestyle change resulted in a loss of two centimeters around the waist as well as improvement in other health measures, such as insulin resistance, the researchers report in the Jan. 9/16 issue of the Journal of the American Medical Association.
Metformin is typically prescribed to help control blood sugar levels in people with diabetes. Previous research has shown that metformin can prevent weight gain in people with diabetes and may help manage weight in some overweight people.
Doctors prescribe atypical antipsychotic (AAP) medications to manage a variety of psychotic disorder and behavioral disturbances, including schizophrenia. However, the drugs often also affect the body's metabolism, resulting in unhealthy cholesterol levels, weight gain and glucose intolerance.
A team based at the Mental Health Institute of the Second Xiangva Hospital, Central South University, China, tested the effect of metformin and lifestyle changes, together and separately, on the weight and insulin levels of 128 adults with schizophrenia. All the participants had gained at least 10 percent of their body weight after starting antipsychotic medications.
The participants were randomly assigned to one of four groups for 12 weeks, while continuing their medication: One group received a placebo or sugar pill; the second one received 750 milligrams per day of metformin; the third received 750 milligrams per day of metformin with lifestyle intervention; and the fourth went through the lifestyle intervention alone. The lifestyle interventions included health education, diet and exercise.
An analysis of the data found that patients in the combination group and patients who took either metformin or engaged in lifestyle change all reduced their weight, body-mass index (a measure of height and weight), waist circumference, insulin levels and insulin resistance.
The participants who took metformin and changed their diet and exercise saw a decrease of 1.8 in their body-mass index, 3.6 in insulin resistance and lost two centimeters in waist circumference. Metformin alone resulted in an average loss of 1.2 in body-mass index, 3.5 in insulin resistance and 1.3 centimeters from the waist. Those who only exercised and changed their diet saw a loss of 0.5 in body-mass index and 1.0 in insulin resistance, but they were no slimmer at the waist. People who took the placebo continued to increase in body mass, waist and insulin resistance, said the researchers.
More information
To learn more about how to increase physical activity, visit the U.S. Department of Agriculture.
THURSDAY, Jan. 3 (HealthDay News) -- Failing to sleep deeply for just three nights running has the same negative effect on the body's ability to manage insulin as gaining 20 to 30 pounds, diabetes researchers report.
In fact, young adults who do not get enough deep sleep may be increasing their risk of type 2 diabetes, according to a study published Dec. 31 in the Proceedings of the National Academy of Sciences.
According to the researchers, three nights of interrupted sleep effectively gave people in their 20s the glucose and insulin metabolisms of people three times their age.
Previous studies have demonstrated that not getting enough hours of sleep affects the body's ability to manage blood sugar levels and appetite, increasing the risk of obesity and diabetes. This current study provides the first evidence linking poor sleep quality -- specifically the loss of deep or slow-wave sleep -- to increased diabetes risk, said the University of Chicago Medical Center research team.
"These findings demonstrate a clear role for slow-wave sleep in maintaining normal glucose control," lead author Dr. Esra Tasali, assistant professor of medicine at the University of Chicago Medical Center, said in a prepared statement. "A profound decrease in slow-wave sleep had an immediate and significant adverse effect on insulin sensitivity and glucose tolerance," Tasali said.
The researchers suggested that improving the quality of sleep, especially for people as they age or if they are obese, could be an important step in preventing the onset of type 2 diabetes.
The researchers recruited five men and four women, all lean and healthy, who were between the ages of 20 and 31. The researchers first observed the participants for two nights of uninterrupted sleep, during which they slept for 8.5 hours, to establish their normal sleep patterns.
Then they observed the same participants over a three-night study period, during which the researchers deliberately disturbed their sleep when their brain waves indicated the beginning of slow wave sleep.
The sounds used to interrupt the sleep patterns were loud enough to move the participants to a different level of sleep but not loud enough to fully wake them. According to the researchers, the participants could recall hearing between three and 15 noises at night, although they were interrupted on average 250 to 300 times. The interruptions increased in number each night, as the participants' need for deep sleep increased.
"This decrease in slow-wave sleep resembles the changes in sleep patterns caused by 40 years of aging," Tasali said. Young adults spend 80 minutes to 100 minutes per night in slow-wave sleep, while people over age 60 generally have less than 20 minutes. "In this experiment," she said, "we gave people in their 20s the sleep of those in their 60s."
At the end of each study, the researchers gave intravenous glucose (a sugar solution) to each subject, then took blood samples every few minutes to measure the levels of glucose and insulin, the hormone that controls glucose uptake.
When the researchers analyzed the data they learned that the participants were almost 25 percent less sensitive to insulin after nights of interrupted sleep. As their insulin sensitivity declined, they needed to make more insulin to process the same amount of glucose, or blood sugar. However, in all but one subject, their bodies did not make more insulin. As a result, they had 23 percent more blood-glucose, the equivalent of glucose levels in an older adult with impaired glucose tolerance.
The researchers also found that the participants who typically had the least amount of slow-wave sleep during the nights they were not interrupted experienced the greatest decline in insulin sensitivity during the study.
More information
To learn more about sleep, its health benefits and how to improve sleep quality, visit the American Academy of Sleep Medicine 
.