People who snore, have trouble falling asleep or who wake up in the morning feeling fatigued have an increased risk of developing conditions tied to diabetes and heart disease, a study found.
Adults who reported frequent loud snoring had twice the risk of developing metabolic syndrome -- conditions that include obesity, high blood pressure and diabetes -- in a three-year follow-up, compared with quieter sleepers, according to a study published in the journal Sleep. The risk jumped 80 percent in people who had difficulty falling asleep and 70 percent in those who reported their sleep wasn’t refreshing.
Previous research has linked sleep duration and sleep apnea, in which patients have pauses in breathing while they sleep, and the risk of individual components of metabolic syndrome. This report is the first to examine the relationship between sleep problems commonly reported to doctors and metabolic syndrome, said Wendy Troxel, an assistant professor of psychiatry and psychology at the University of Pittsburgh.
“Sleep problems aren’t just an annoyance but something with potential major public health ramifications,” Troxel said in a telephone interview. “Sleep complaints aren’t just the problems of the ‘worried well,’ they could foreshadow significant physical health problems.”
The study followed 812 people who didn’t have metabolic syndrome at the beginning of the three-year period. The patients underwent yearly checkups to determine whether they were developing metabolic syndrome and sleep disturbances were measured via a questionnaire.
Loud snoring may be a problem for the heart independent of its relationship with sleep apnea, the study showed. A sample of 290 patients were evaluated for sleep apnea and those without were three times more likely to develop metabolic disease.
“Loud snoring independent of apnea has adverse consequences,” Troxel said.
This may be because vibrations from snoring damage the layer of cells that line the inner part of blood vessels, triggering inflammation, Troxel said.
The study doesn’t show whether sleep problems cause metabolic syndrome, since researchers didn’t manipulate patients’ sleep. Further studies are needed to determine if sleep disorders and snoring cause metabolic syndrome, or are symptomatic of it, Troxel said.
For instance, difficulty falling asleep could reflect stress, which is a known risk factor for cardiovascular disease, Troxel said.
“These symptoms may happen in people who don’t experience insomnia as a syndrome,” Troxel said. “If you’re experiencing these symptoms three times or more a week, you should address it with your primary care provider.”