Medicine is perfect for heartwarming stories. Some close relative is facing the most hopeless prognosis, such as being in a vegetative state. Someone tries a wild treatment, and boom, people are crying, the relative is awake, and the headlines go viral. But science doesn’t really work this way.
A man recently “woke” from a vegetative state, crying again after “regaining consciousness,” creating a flurry of news coverage. Yet as exciting as this sounds, the case came with plenty of caveats. Many headlines rightly imply that the man was only minimally conscious, not much better than a vegetative state. He also died before the scientists published their paper. The truth is that you shouldn’t raise your hopes too high after single case studies.
As we wrote last month, a team of French scientists shot some electricity into the longest nerve (the vagus nerve) in the man’s brain for a month. They reported in their paper that the man moved from a vegetative to a minimally conscious state, going from a five to a 10 on the 23-point Coma Recovery Scale. That’s still a low score, though. New Scientist reported that the patient’s eyes widened when the researchers moved in close and he seemed to cry. He couldn’t say his name or demonstrate that he knew where he was. Also, his score was 10 for only a few days, after which it dropped down to a 6-8.
Stories like these always seem hopeful – signs of improvement can imply continued improvement. The Guardian later reported that the patient died after the study was over but before it was published, even though the study’s lead author withheld the fact and even implied that the patient was still alive.
It’s great to feel optimistic about this kind of progress if you’re hoping to one day see patients awake from many-year comas. But this work was based on a single case study published in Current Biology. That’s not how science works. What if it was a fluke, or the patient woke up on their own, or something else the scientists did actually caused the patient’s eyes to open? As blogger Neuroskeptic pointed out to me in an email, “The raters are also not mentioned as being blinded i.e. I think they knew all about the vagus stimulation. This raises the possibility of observer bias.”
That’s the point of blinded clinical trials. While they can be difficult to do and costly, trying a treatment on many people can at least confer some level of confidence that it will work, set realistic expectations, and isn’t based on the observers thinking it works because they want it to work.
Single cases like these are important and exciting. But we shouldn’t let the mask of a good story oversell what really happened. In this case, a man in a vegetative state began moving his eyes, and then died.