ATLANTA (CNN) -- Deaths caused by congestive heart failure are down, particularly among black adults, according to a report released Thursday by the Centers for Disease Control and Prevention.

The study, covering years 1988 through 1995, found deaths from heart failure decreased 3 percent a year for black men and 2.2 percent a year for black women. For all elderly adults, heart-failure deaths fell 8 percent in the period.

But the report also says that although death rates are down, the number of heart failure cases is rising.

Researchers said possible reasons for the decline include improvements in treating risk factors, increased access to appropriate medical care and changes in death certificate coding.

Kathy Harben of the CDC said doctor education is still an obstacle in treating heart failure.

She said that while cardiologists know that drugs, such as ACE inhibitors, can help the condition, general practitioners may not. Also, heart failure often doesn't get as much attention as heart attacks and stroke.

Uncontrolled high blood pressure and heart attacks are the biggest underlying causes of heart failure. High blood pressure weakens heart muscle; heart attacks damage and destroy the muscle.

Heart failure happens when the weakened heart can no longer pump a sufficient amount of blood. Symptoms include shortness of breath, fluid retention and fatigue.

According to the American Heart Association, heart failure is the leading cause of hospital admissions in people over age 65. The association figures from 1993 show that blacks are about 40 percent more likely than whites to die of heart failure.

In 1995, 94 percent of the 46,484 deaths from heart failure occurred in people 65 and older.