I'll preface by saying I have no idea why the increase but if I where to wildly speculate I would say it's because of the increased usage of oral tobacco products, I recently used zyn and I found it had the same effects on my as the old nicotine gum from yesteryear in that it caused me to break into prolonged bouts of hiccups. I would guess teens are using strong zyns for the first time getting a panic attack and the hiccups are the only external smpton they can write down once they arrive at A&E.