Why 40 to 80 Percent of Concussions Never Reach Your Medical Record

You went back and pulled your medical records, hoping to find an explanation. You scrolled through years of visits and found nothing about the day you got your bell rung. No note about the car accident, the fall off the ladder, the hit in the game, the fight, or the blast that left your ears ringing. There is nothing in your chart, and that silence can feel like proof that the moment did not matter. It is not. When 40 to 80 percent of these hits never make it onto paper, an empty record is exactly what you should expect to find.

Why the moment disappeared from the record

Most people who take a hit to the head never see a doctor for it. You shook it off. You told yourself you were fine because you could still walk and talk. The people around you agreed, because on the outside you looked fine. There was no scan, no diagnosis, no line item to bill. An unreported concussion is not a rare accident of paperwork. It is the ordinary path a bell-ringing hit takes through most lives.

Some of the reasons are simple, and they add up quietly:

• The symptoms often surface hours or days later, long after the moment felt survivable.
• Nothing bled and nothing broke, so it did not feel like a medical event worth a visit.
• The culture around sports, work, and military service rewards playing through it.
• Many hits happen to kids and teenagers whose parents were never told what it might mean decades on.
• Even when someone did go in, a normal imaging result often closed the file, because standard scans are not built to see this.

So the record stays blank, and years pass. Then, sometimes long after you have forgotten the hit entirely, a heaviness settles in that does not seem to have a reason attached to it.

How an old hit can echo years later

Here is the part that rarely gets explained plainly. A head impact is not always a closed chapter once the headache fades. People who took a bell-ringing hit are more than three times as likely to carry depression, and that elevated risk persists for years afterward (Beaton et al., 2020, Frontiers in Neurology). The connection is real even when the timeline is long enough that no one thinks to draw the line between the two.

The effects show up in other systems too, which is part of why they get missed. Sleep disorders affect roughly 30 to 70 percent of people with a head-injury history. Up to about one in six develop a hormone deficiency after a hit, with pooled prevalence near 16.8 percent. And in the largest long-term follow-up, roughly half of people who took a bell-ringing hit were not back to their old baseline years later (TRACK-TBI, 5-year outcomes). None of this means you are broken. It means the moment left a footprint, and the footprint deserves to be looked at rather than dismissed.

Why the usual treatment sometimes does not land

Maybe you already tried the standard road. You told a doctor you felt low, you were handed an antidepressant, and it did very little. That experience is common, and it is not a personal failure. In a meta-analysis, antidepressants given after a head impact showed no significant difference from placebo (Foreman et al., 2019, J Head Trauma Rehabil). Read that slowly. The most common tool sometimes does not move the needle for this particular group.

The likeliest reason is mechanical, not moral. Most familiar antidepressants work on serotonin. But depression that traces back to an old hit can run on a different system in the brain, one built around a signaling chemical called glutamate. If the low mood is running on glutamate and the medication is aimed at serotonin, the two can pass each other in the dark for years. That is often why standard care missed it: it was looking in a reasonable place, just not the place where this particular problem lives.

An empty medical record does not mean nothing happened. It usually means no one was looking with the right lens at the right system.

What a different lens can see

This is where the science on glutamate becomes relevant. Ketamine and its cousin esketamine act on the glutamate system rather than serotonin, with effects that can be measured in hours and a neuroplasticity window that opens roughly 24 to 72 hours afterward (Zanos and Gould, 2018, Molecular Psychiatry). To be clear about what that does and does not mean: an old head injury is a risk factor for treatment-resistant depression, never an instruction to reach for any one medication. Spravato (esketamine) is FDA-approved for treatment-resistant depression. It is not approved for concussion, and no one can promise you an outcome.

What matters is the diagnostic question underneath all of it. If your depression has not responded to the usual road, the useful move is to ask why, out loud, with someone trained to trace it back to its source. A proper evaluation from a clinic that has neurology on staff can look at this history, connect it to what you are feeling now, and tell you whether the standard road missed something. Neurology on staff is a lens for understanding the why. It is a diagnostic capability, not a guarantee.

If the weight has gotten very heavy

One more thing needs to be said gently and directly. Research has found elevated odds of death by suicide among people with a concussion history (Erlangsen et al., 2018, JAMA). If you are in that dark place right now, you are not weak and you are not alone, and there is a real reason your mind feels the way it does. Please call or text 988, the Suicide and Crisis Lifeline, and talk to a person tonight. There are also gentler long-range reasons to take an old hit seriously: one national registry found a history of head injury was associated with about a 24 percent higher long-term dementia risk (Lancet Psychiatry), which is simply one more argument for understanding your own history rather than ignoring it.

So if you searched your chart and found nothing, let that fact rest more easily now. The blank space is ordinary. The hit was real, the way you feel is real, and the two may be connected in a way no one ever paused to explain. Understanding that connection is not the end of the story. For a lot of people, it is the first honest beginning.