If you have hypertension, diabetes or heart disease, getting enough sleep at night is imperative, a new report said.

Researchers from the Pennsylvania State College of Medicine followed more than 1,600 adults for about 20 years and found that combining these illnesses with sleeping less than six hours nightly was a "deadly combo."

They found those who had high blood pressure or diabetes and typically slept for less than six hours a night were twice as likely to die from heart disease or stroke. And subjects with heart disease or stroke, who typically slept for less than six hours nightly, were three times as likely to die from cancer.

On the other hand, sleeping more than six hours nightly eliminated the early-death risk.

"Our study suggests that achieving normal sleep may be protective for some people with these health conditions and risks," lead study author Julio Fernandez-Mendoza said.

The team said short sleep duration can be used to predict long-term health outcomes.