Mojo (see post above) has already pointed out that you used strokes as an example of societal sin. Specifically, you cited overworking employees. Of course, that would actually apply to the U.S. more than Europe. Another contributing factor in strokes is age. Thus, the longer the average lifespan in any society, the higher the percentage of the population suffering from strokes.
But I do believe many (I do not know if all of them are) are caused by the sin of humanity. And that includes not just personal sin but the sin of society as well. A societal sin could be indifference to the poor, or lack of proper medical care by a society that could afford proper medical care for its people.
Also there is the sin of omission. For example everyone might say how great Bill Gates is to give a certain amount to charity. But if he for example gives 2 billion but could actually afford to give 10 billion then that is a sin of omission.
Concerning the hilited areas above: First, a general sin of humanity would seem to imply original sin, which, of course, should affect all of us equally.
As to societal sin, particularly the ones you cite, indifference to the poor and lack of medical care for its people; again, this fits the U.S. far more than Europe. It also fits the U.S. far more even than Canada. Perhaps this explains the U.S. mental illness rate that is over twice Canada's, even though the two countries have comparable rates of church attendance and comparable standards of living.
Also, as I noted - and you have yet to respond to this - once strokes and dementias are removed, the 38% of the European population suffering from mental illness drops down to about 27%, comparable to the rate of mental illness in the U. S. in an earlier study that also didn't include strokes and dementias.
Finally, do you really have any information on Bill Gates, or is this all hypothetical?