Combining Abbott Laboratories' cholesterol pill Niaspan with an older medicine, called a statin, reduced plaque buildup more than the statin alone, a study found.

Patients taking Niaspan and a statin had a 1.1 millimeter reduction in the thickness of their arteries over 12 months, researchers said in a study released today by the Journal of the American College of Cardiology. Those taking just a statin had an increase in arterial thickness.

The finding comes two weeks before a separate study, called Arbiter 6-Halts, comparing Merck & Co.'s cholesterol pill Vytorin to Niaspan using a similar measurement technique, is scheduled to be presented at a meeting of the American Heart Association in Orlando.