Chronic Insomniacs Have Higher Hypertension Risk

February 1, 2015
Eileen Oldfield Associate Editor

What's keeping insomniacs awake at night might also be raising their blood pressure.

What’s keeping insomniacs awake at night might also be raising their blood pressure.

Chronic insomnia combined with taking more than 14 minutes to fall asleep increased the odds of hypertension by 300%, according to a new study published in the American Heart Association journal Hypertension. In patients with chronic insomnia who took longer than 17 minutes to fall asleep, the odds of developing hypertension increased to 400%.

“Long latency times to fall asleep during the day may be a reliable index of the physiological severity of the [sleep] disorder,” said Alexandros Vgontzas, MD, professor of sleep research and treatment in the Department of Psychiatry at Pennsylvania State University College of Medicine, in a press release.

Researchers studied 219 chronic insomniacs and 96 normal sleepers to analyze links to hypertension. Participants spent 1 night monitored in a sleep lab, and then took a Multiple Latency Sleep Test the next day. Participants were allowed 4 opportunities for 20-minute naps during monitoring.

Half of the participants took 14 minutes or less to fall asleep, and the other half took longer than 14 minutes to fall asleep. Those in the latter group were considered “hyperaroused.”

Researchers based their hypertension designation on either blood pressure measures or a physician’s diagnosis. They controlled for obesity, sleep apnea, diabetes, smoking, and other confounding factors.

Insomnia is the most prevalent sleep disorder, affecting one-fourth to one-third of the general population. Approximately 10% of patients have chronic complaints and seek medical help for the condition.

Although insomnia is considered a nighttime disorder, several studies suggest that it occurs at any time during the day. The type of insomnia associated with 24-hour hyperarousal is considered more severe and has significant cardiometabolic consequences.

Furthermore, feeling hyperalert or sleepy does not allow people to function at their best, feel well during the day, or sleep well at night, Dr. Vgontzas said.

“Although insomniacs complain of fatigue and tiredness during the day, their problem is that they cannot relax and that they are hyper,” Dr. Vgontzas said. “Measures that apply in sleep-deprived normal sleepers—napping, caffeine use, or other stimulants to combat fatigue—do not apply in insomniacs. In fact, excessive caffeine worsens the hyperarousal.”