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That's a meaningless statistic on its own. Does it shorten 5.4% of people's lives by 5 minutes each? or does it kill 5.4% of people while they're children? The reality will be somewhere between those extremes but the number alone tells us nothing interesting.

You can use something like years of life lost instead: http://www.who.int/whosis/whostat2006YearsOfLifeLost.pdf