Thursday, December 26, 2013

CPAP may improve golf performance

Regular golfers often have a handicap - a measure of their golfing ability. This allows them to play against other players of different skill levels. The lower the handicap, the better the golfer. This study assessed whether CPAP improved golf handicaps in regular golfers with at least moderate obstructive sleep apnea (OSA). The study authors included golfers without OSA as a control group. Compliance with CPAP was monitored digitally from the CPAP machine itself.

The results showed that the control group did not improve their handicap scores, but the CPAP user group did. The improvement was more dramatic with the better golfers (Handicap < 12). Of note, the golfers were very compliant with their CPAP use - using them for 6.3 hrs per night for 91% of nights.

The authors concluded that the handicap scores improved due to regular CPAP use. They theorized that CPAP use can improve cognitive functioning, and this was what improved golf performance.

The authors note that getting patients to use CPAP is a challenge - perhaps this study will give some OSA patients motivation to use their CPAP.

Wednesday, December 18, 2013

Caffeine and sleep disruption

Most of us have used caffeine. And most of us have heard that caffeine consumed close to bedtime can worsen sleep quality. I tell my patients to not have caffeine within 8 hours of desired bedtime. This was what I was taught in sleep fellowship. Apparently, there are few studies that have determined that people should stop consuming caffeine within so many hours of bedtime.

This study sought to determine how caffeine affects sleep quality when taken at bedtime and at 3 and 6 hours prior to bedtime. It's a small study, with only 12 healthy, younger volunteers. The volunteers did not have insomnia but did consume caffeine regularly. Sleep was measured by subjective report and by objective home monitoring. The results showed that the 400mg of caffeine negatively impacted sleep quality when taken at bedtime and at 3 and 6 hours prior to bedtime. Interestingly, caffeine affected both subjective and objective sleep quality when it was taken at bedtime and 3 hours before bedtime. However, the study participants did not report reduced sleep quality when caffeine was consumed 6 hours prior to bedtime. But objective home measurement showed that the caffeine taken 6 hours prior to bedtime did negatively impact sleep. This lack of perceived disruption in sleep quality may explain why some patients ignore recommendations to eliminate caffeine consumption close to bedtime.

Wednesday, December 11, 2013

Snoring, sleepiness, and cardiovascular disease

Snoring is common. Habitual snoring is defined as occurring at least 3 days per week. Studies show that 10 - 20% of women and 29 - 39% of men snore habitually. Almost all of my patients with obstructive sleep apnea (OSA) snore, but not all snorers have OSA - studies show that over a third of snorers do not have OSA. Studies have not convincingly linked snoring without OSA to cardiovascular disease (CVD).

Studies have shown that OSA without subjective sleepiness does not increase CVD risk as much as those with OSA that do report sleepiness. This study sought to determine if people who snore and are sleepy, but do not have a history of OSA are at increased risk of developing CVD. Researchers studied >2000 healthy men and women with an average age of 73.5 years. Snoring and sleepiness were assessed with self-report questionnaire. Participants were followed for 10 years on average.

Results showed that 36% of those that reported habitual snoring and sleepiness developed CVD. In contrast, only 22% of those with no snoring or sleepiness, 23% of those with sleepiness but no snoring, and 26% of those with snoring but no sleepiness developed CVD. The researchers concluded that sleepy snorers had a significantly greater risk of developing CVD than the other groups.

However, these results must be interpreted cautiously. First, OSA was not ruled out in all participants with a sleep study. Second, self-reported snoring is not reliable - especially if there is no bedpartner to report it. Also, the authors admitted that the association between sleepy snorers and CVD disappeared when the way they asked about sleepiness was more stringent.

Wednesday, December 4, 2013

CPAP therapy may improve blood pressure in resistant high blood pressure

Obstructive sleep apnea (OSA) has been linked to high blood pressure (HTN). In fact, one cause of reversible HTN is untreated OSA. And sometimes we see improvement in HTN with treatment of OSA, especially severe OSA. Here is a study that showed just that. Researchers studied patients with resistant HTN and moderate-to-severe OSA. The results showed that blood pressure dropped significantly after 6 months of CPAP therapy, compared to those patients who did not receive CPAP therapy.