Do you often wake up feeling unrefreshed and remain tired throughout the day? Do you experience morning headaches or difficulty with memory and concentration? Your problem could be sleep apnea. Obstructive sleep apnea causes the airway to narrow and breathing to slow or stop for brief periods, usually many times each night. During these episodes, blood oxygen levels go down and carbon dioxide levels go up. This triggers alarms throughout the body and increases the risk of high blood pressure, heart disease and stroke.

The single greatest risk factor for sleep apnea is obesity. This column previously cited data from the Congressional Budget Office noting that from 1987 to 2007 the fraction of overweight adults increased to 63 percent from 44 percent while the share of obese adults more than doubled to 28 percent from 13 percent. That trend continues to the present day.

The Wisconsin Sleep Cohort Study evaluated a random sample of 602 middle-age adults between 30 and 60 years old. It found that, regardless of weight, 9 percent of women and 24 percent of men suffer from significant sleep apnea. The rate is even higher for those who are overweight.

The cost to society is profound. Sleep apnea has been shown to increase medical costs and, according to one study, results in $3.4 billion of additional health care services in the U.S. annually.

Sleep apnea causes not only increased costs from medical illness. Another study of 800 subjects determined that sufferers are “twice as likely as people without sleep apnea to have a car crash, and three to five times as likely to have a serious crash involving personal injury.” This has profound implications for all workers who drive for a living or who must be around heavy machinery.

Workplace productivity also suffers from sleep fragmentation and nightly changes in oxygen and carbon dioxide levels. Research has shown that work performance can be decreased by 30 percent.

What is most worrisome is that up to 80 percent of people with sleep apnea have gone undiagnosed, even among those with reasonable access to health care. The military has seen a substantial increase in sleep apnea associated with obesity in retired veterans, and in Hawaii recently expanded its sleep lab facilities. Despite the additional capacity, there is still unmet demand for diagnostic services that have to be outsourced to the medical community on Oahu.

The obesity epidemic has a ripple effect that touches every aspect of our society. One such ripple is its sister epidemic, obstructive sleep apnea. More education is needed both for the public and for primary care providers. Hawaii clearly needs to increase its capacity to diagnose and treat this vexing problem.

Does that sound expensive? It is. We also need to get at the root of the problem. Maybe next year the legislature will revisit its debate on the soda tax. Reducing the consumption of sugared water won’t solve the entire problem, but it will help.