"The sample of those who were studied included individuals between ages 55 and 65 who had had any kind of outpatient care in the previous three years. The 1,824 participants were followed for 20 years."

So how many heavy drinkers died before they got old enough to be included in the study? The diseases and other death-dealing agents (accidents, violence, suicide) associated with heavy alcohol use often lead to early deaths. The study doesn't address that issue at all, only the relative mortality rates of heavy drinkers, moderate drinkers, and non-drinkers who had already managed to live to be at least 55.

I've not yet reached the age where members of my own age group are dropping like flies due to natural causes. They still mostly do themselves in by driving into phone poles, committing suicide, getting murdered by angry boyfriends, etc. Alcohol is almost always a factor in their deaths.