WASHINGTON (AP) — Some good health news: Americans’ cholesterol levels are dropping, and more people at especially high risk are getting treatment.

Researchers say Monday’s report suggests a controversial change in recommendations for cholesterol treatment may be starting to pay off.

“It is very heartening,” said Dr. Pankaj Arora of the University of Alabama at Birmingham, who led the study. “But there is more to do.”

Heart disease is the world’s leading killer and high cholesterol is a key risk factor — but not the only one. Doctors long treated patients based mostly on their level of so-called “bad” cholesterol, whether they had other risks or not. In 2013, national guidelines urged them instead to focus more on people’s overall heart risk, by taking into account age, blood pressure, diabetes and other factors. Those at highest risk would get the most benefit from cholesterol-lowering statin drugs.

The Alabama team examined records from the Centers for Disease Control and Prevention that tracked cholesterol information from more than 32,000 adults between 2005 and 2016.