Coffee drinkers can take heart from a series of studies presented this week at American Heart Association conferences in San Francisco. For example, coffee drinkers appear to have a lower risk of hospitalization for abnormal heart rhythms. And there's no indication that having a few cups every day increases the risk of atherosclerosis, the thickening of blood vessel walls that can lead to heart attacks and other problems. What's more, something in coffee other than caffeine might be responsible for a reduced risk of diabetes for women who regularly imbibe java. But it may be linked to a slight rise in high blood pressure