Ummm.. firstly, stress comes in all forms and from all aspects of life. I would think a divorce or a family problem is much more difficult to cope with in terms of stress than a monetary loss - well, maybe not if the family problems are a result of trading losses, is it possible that the trading profession sees this type of familial scenario more often than other professions?
Secondly, I don't equate trading with stress, I would think it is more akin to anxiety. Stress is physiological and can actually bolster performance in many cases. Anxiety is what I feel when in a loser, cut the loser and the problem is solved.
With the above in mind, stress and/or anxiety doesn't necessarily lead to alcoholism. While I'll venture to say that alcoholism may cause greater stress because it is a proven depressant (a hangover is a chemical imbalance of seratonin thus causing a mild form of depression), I think some people just plain enjoy drinking a good beer if not several - I sure do.
In general, I think this topic is trite. People from all walks of life have been consuming alcohol for thousands of years. A better statistic would involve simple lifestyle choices - smoking, eating, excersize and the prevelance of heart disease (the #1 cause of death in the US). Alcohol is one small piece of the picture. Do traders have lesser health and a higher statistic of stress related diseases would be an interesting study.
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