Most of us have had a hiccuping fit at some point in our lives. They are incredibly annoying, uncomfortable, and awkward, but at least these involuntary diaphragm contractions go away pretty quickly, right? Think again. Long-term hiccuping fits, known as intractable hiccups, are more common than we'd thought, according to new science published in Current Neurology & Neuroscience Reports. Hiccups become classified as "intractable" when they last for more than four weeks, and the number of people they affect, according to the study, is kind of astonishing.
Hiccups happen in a lot of cases because of drinking or eating too fast, and it's thought that it has to do with our evolutionary history. At a distant point in the history of humans, we evolved from water-breathers with gills to air-breathers who inhale through our noses and mouths. Hiccups, it seems, are an "interim" behavior that might be left over from an evolutionary period where we had both gills and nostrils. According to this theory, we're rather like tadpoles, who have gills and mouths, and "hiccup" when they breathe in water through their mouths, forcing the water out through the gills. Of course, humans lack gills, so it's a behavior that doesn't have much relevance to our current bodies. But that doesn't stop it being incredibly common — like, way more common than you'd expect.
According to the new data, hiccups cause hospitalization for around 4,000 people in the U.S. every year. If you've only experienced them for around two days, they're classed as "persistent", but a month-long spell — or longer — places you in the "intractable" category, and that's where things really get interesting.
We're still trying to understand what causes hiccups to last forever. The longest recorded case of hiccups, according to the Guinness Book Of Records, lasted 69 years and 9 months, in an Iowan farmer who reported that he'd started experiencing them after lifting a 350-pound hog to weigh it and falling over. Among the many causes that may be involved in intractable hiccups, the scientists behind the latest study explain, are spine disease, brain abscesses and injuries, and various medications using neurotransmitters, because hiccups involve a bunch of neurotransmitters sending the signal for the contractions to happen.
What else raises the risk of intractable hiccups? Being male and over 50, for one thing. A whopping 91 percent of the cases the study covered were of men, according to a press release on the study. It's also common to get serious hiccups of various kinds if you've got a gastrointestinal, cardiovascular or nervous system illness, although according to the cases in this study, they've also been caused by things as diverse as arthritis and blood clots. And they're not fun; hiccuping interrupts sleep, breathing and eating. The world of the intractable hiccup is a strange one, and it's usually a symptom of something more serious rather than just a curiosity.
So if you've started experiencing hiccups that just will not go away, no matter how much you drink upside down, gargle salt water and ask other people to scare you, it's worth waiting 48 hours and then seeing a GP. Hiccups that last for a long period are far less rare than we thought — but let's hope you don't end up in the record books because of it.