Among all groups, heavier people were much more likely than thinner people to suffer from the symptoms.
The study estimates that these numbers have gone up by 14 percent to 55 percent from 1988-1994 to 2007-2010. Peppard estimated that 80 percent to 90 percent of the increase in symptoms is due to the growth in obesity.
But it's hard to know for sure how much of a role that obesity plays in causing more symptoms. While obesity is "almost certainly the biggest factor" in causing sleep apnea, Peppard said, "there's long list of things that cause sleep apnea or are related to sleep apnea, like being older, being male, having a narrower upper airway, having a genetic predisposition to it..."
What to do? If you don't feel rested after sleeping, Peppard said, talk to your doctor.
The good news is that sleep apnea is treatable. One treatment, known as continuous positive airway pressure (CPAP), is a machine that blows air into the throat to keep it open while people sleep. "It's very effective, but some people don't like to use it," Peppard said.
There's another option that will help in many cases, he said: Weight loss.
Joyce Walsleben, an associate professor of medicine at New York University who studies sleep problems, agreed. "Obesity has to be addressed and controlled," said Walsleben. "That is a message for doctors and patients."
Although the study tied obesity to higher risk of having sleep apnea, it did not establish a cause-and-effect relationship.
The study appeared online recently in the American Journal of Epidemiology.