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.
They also said 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.
According to the Centers for Disease Control and Prevention, adults should get at least seven hours of sleep a night.
“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 in a statement.
The team said short sleep duration can be used to predict the long-term health outcomes of those with chronic illnesses.
In fact, they believe policy makers should help ensure sleep consultations and assessments “become a more integral part of our healthcare systems,” they said.
Fernandez-Mendoza concluded, "Better identification of people with specific sleep issues would potentially lead to improved prevention, more complete treatment approaches, better long-term outcomes and less healthcare usage."