When former professional football players report memory problems, depression, or difficulty concentrating, the conversation almost always turns to head injuries. Chronic traumatic encephalopathy — CTE — has dominated the public understanding of post-career cognitive decline in contact sports, and for good reason. But a new study published in Neurology raises an uncomfortable question: what if a significant portion of these symptoms is coming from something treatable that almost no one is checking for?
The study, led by investigators at Vanderbilt Health and the Football Players Health Study at Harvard University, examined nearly 2,000 former professional football players and found that obstructive sleep apnea may affect up to 69% of them — more than double the 32% who had actually been diagnosed.
The untreated and undiagnosed cases weren't just a footnote. They were associated with significantly worse anxiety, depression, chronic pain, and cognitive problems — the same cluster of symptoms that drives many former players to believe they have CTE.
The Diagnosis Gap
The numbers are striking. Of the nearly 2,000 former players in the study:
- 32% had been formally diagnosed with sleep apnea
- An additional 37% screened positive on a validated sleep apnea instrument but had never been diagnosed
- Of those who had been diagnosed, more than half were not regularly using CPAP or other treatment
That means roughly two out of three former players may be living with a condition that fragments their sleep, drops their oxygen levels dozens of times per night, and progressively damages their cardiovascular and neurological health — and most either don't know they have it or aren't treating it.
Why Football Players Are at Elevated Risk
The physical profile of a professional football player — particularly linemen and other large-body-frame positions — maps almost perfectly onto the risk factors for obstructive sleep apnea:
- High body mass index: Many players maintain elevated weight during their careers, and weight gain after retirement is common
- Thick necks: Neck circumference is one of the strongest predictors of airway collapsibility during sleep
- Male sex: Men are two to three times more likely to develop sleep apnea than women
These risk factors don't disappear after retirement. In many cases, they worsen as players age, gain weight, and lose the cardiovascular fitness that partially offset their body composition during active play.
But the connection may go deeper than anatomy. Research has shown that traumatic brain injury itself increases the risk of developing sleep-disordered breathing. The repeated head impacts sustained over a football career may alter brainstem function in ways that compromise airway control during sleep — meaning the same exposures that raise concern about CTE may also be causing sleep apnea.
The Symptom Overlap That Matters
Here is where the study has implications beyond sports medicine. The cognitive and psychiatric symptoms of untreated sleep apnea are remarkably similar to those associated with CTE:
| Symptom | Untreated Sleep Apnea | CTE |
|---|---|---|
| Memory problems | ✓ | ✓ |
| Difficulty concentrating | ✓ | ✓ |
| Depression | ✓ | ✓ |
| Anxiety | ✓ | ✓ |
| Irritability | ✓ | ✓ |
| Chronic fatigue | ✓ | ✓ |
| Impaired decision-making | ✓ | ✓ |
The critical difference: CTE cannot be diagnosed in living patients and has no known treatment. Sleep apnea can be diagnosed with a sleep study and treated effectively with CPAP, oral appliances, or other interventions.
A previous survey found that one in three former NFL players believes they have CTE. Researchers involved in that study noted that many of the symptoms driving that belief — depression, sleep problems, cognitive complaints — are treatable conditions that can mimic neurodegenerative disease. An erroneous or unverifiable CTE diagnosis could discourage players from pursuing treatment for conditions that might actually improve with intervention.
The Cost of Not Screening
The Vanderbilt-Harvard study did not set out to challenge CTE research. Its focus was narrower: characterizing sleep apnea prevalence and its association with neuropsychiatric symptoms in a population at high risk for both.
But the findings carry a practical implication that the authors emphasize: sleep apnea is a modifiable risk factor. Unlike CTE, which currently cannot be treated or even confirmed during life, sleep apnea can be identified with routine screening and managed with established therapies.
For a former player experiencing memory loss, mood changes, and declining quality of life, the difference between "you may have irreversible brain damage" and "you have a treatable breathing disorder" is enormous — not just medically, but psychologically. The belief that cognitive decline is inevitable and untreatable can itself worsen depression and reduce engagement with healthcare.
What Needs to Change
The study points to several concrete gaps:
Screening: Sleep apnea screening is not standard in post-career health programs for former players, despite the population's extremely high risk profile. The validated screening instruments used in this study are simple questionnaires that could be incorporated into routine assessments.
Treatment adherence: Even among the minority who had been diagnosed, CPAP adherence was poor. This echoes patterns in the general population, where roughly half of patients abandon CPAP within a year, but may be compounded in former athletes by discomfort, stigma, or the perception that their symptoms have a different cause.
Differential diagnosis: When former players present with cognitive or psychiatric complaints, clinicians should systematically evaluate for sleep-disordered breathing before attributing symptoms to concussion history alone. This doesn't mean ignoring the role of head trauma — it means ensuring that treatable conditions are identified and addressed alongside it.
What This Means for Patients
This research is not about dismissing CTE or minimizing the consequences of head injuries in football. Both are serious concerns supported by substantial evidence.
But it is about ensuring that a treatable condition affecting potentially two-thirds of former players is not overlooked because attention is focused elsewhere. For the thousands of former professional and collegiate football players living with undiagnosed sleep apnea, treatment could meaningfully improve their memory, mood, energy, and long-term cardiovascular health.
The first step is simple: a sleep study. For a population this clearly at risk, the case for routine screening is hard to argue against.
