Wednesday, May 28, 2014

CPAP improves blood sugar control

I've blogged before about how patients with obstructive sleep apnea (OSA) are at increased risk of developing diabetes. I've also written about how treating OSA can improve blood sugar control in diabetics. Here is another study that demonstrates long term use of CPAP (5 years) is associated with better control of blood sugar in diabetics. The study also showed that long term use of CPAP was associated with lower blood pressure and improved quality of life. The study authors concluded that CPAP use is a cost-effective treatment option for OSA.

Wednesday, May 21, 2014

Sudden Infant Death Syndrome

Sudden Infant Death Syndrome (SIDS) is the sudden, unexplainable death of a baby less than a year old. The baby usually dies in its sleep. Rates of SIDS have decreased, perhaps due to public health campaigns that emphasize having infants sleep on their back only. But researchers still don't know exactly why SIDS occurs. This article discusses new research showing that the brains of babies who have died of SIDS have a similar histological pattern to those of children who died of accidental asphyxiation. The research showed that the histological pattern of the SIDS babies was different than that of babies who died from head trauma or infection.

Wednesday, May 14, 2014

CPAP use and high blood pressure

Studies have shown that obstructive sleep apnea (OSA) is linked to high blood pressure (HTN). There was a paper in 2012 that was a meta-analysis showing that CPAP significantly reduced both systolic and diastolic blood pressure (DBP). When the researchers looked closer at the data, they discovered that the reduction in DBP occurred more often when the baseline DBP was high, as well as when the patient was excessively sleepy at baseline. The results did not show that reduction in blood pressure was associated with the OSA severity.

In this study, the researchers went back over the original data to further explore the relationship between blood pressure improvement and CPAP therapy. The results showed that the sole predictor of reduction in blood pressure was the presence of uncontrolled HTN at baseline. Again, OSA severity was not related to the reduction in blood pressure seen with CPAP therapy. Also, excessive sleepiness was not a significant predictor in CPAP reducing blood pressure, in contrast to the prior study.

The researchers concluded that patients with OSA who have uncontrolled HTN would have the largest benefit in their blood pressure with CPAP therapy, despite how severe the OSA or how sleepy the person may or may not be.

Wednesday, May 7, 2014

Blood sugar and fat metabolism in narcoleptics treated with sodium oxybate

Narcolepsy is a neurological disorder characterized by excessive sleepiness. It's caused by destruction of a group of neurons in a part of our brain called the hypothalamus. The hypothalamus is important in regulating our hormones, many of which control basic functions like sleep and hunger. Because of the location in the brain, reports have linked narcolepsy to elevated weight and even type 2 diabetes. It's been theorized that patients with narcolepsy have reduced sensitivity to insulin, much like type 2 diabetics.

This study was done to assess both blood sugar and fat metabolism in a small group of narcoleptics and compared them to a matched control group that did not have narcolepsy. They used a sophisticated test to measure both fat and blood sugar metabolism, something that had not been done before in older studies of patients with narcolepsy. The results were interesting in that the researchers found that narcoleptics had increased insulin sensitivity in the periphery - the opposite of what they expected. Liver cell insulin sensitivity and pancreatic function were the same as matched controls. Fat metabolism tended to be lower in patients with narcolepsy, which may explain in part why narcolepsy is linked with being overweight.

The researchers also treated the narcoleptic patients with sodium oxybate, a medicine that improves some of the narcolepsy symptoms. It's taken at night, and improves the patients' sleep quality, although it's not a sleep aid. Interestingly, the sodium oxybate increased fat metabolism, and the narcoleptic patients lost an average of 5.2 kg (11.5 pounds) in the three months of the study. The exact mechanism of the weight loss is not known.

The bottom line is that the results of this study do not support an increased risk of type 2 diabetes in narcoleptics. Also, patients with narcolepsy that are treated with sodium oxybate may lose weight, although the exact mechanism is unclear.