Body Mass Index and Sleep Disorders After TBI

What is the study about?

This study looked at the connection between body weight, sleep problems, and recovery after a moderate-to-severe traumatic brain injury (TBI). TBI means a serious injury to the brain caused by a bump, blow, or jolt to the head.

What did the study find?

The study had three main findings:

1. Higher body weight at the time of rehabilitation was associated with a greater risk of developing a new sleep disorder after TBI, with overweight and obese individuals more likely to experience sleep problems. 
2. New sleep disorders after TBI were more common in younger individuals and those with more severe injuries, suggesting a link between sleep disorders and more serious TBIs.  
3. Developing a new sleep disorder was also linked to poorer recovery, with over a 50% higher likelihood of unfavorable functional outcomes and greater difficulty with daily activities and returning to work.

Additionally, most participants were overweight or obese at rehabilitation admission, and those who developed sleep disorders reported higher levels of depression and anxiety one year after injury, further complicating recovery.

Who participated in the study?

This study used data from the Traumatic Brain Injury Model Systems (TBIMS) National Database, which tracks long‑term outcomes after moderate‑to‑severe TBI. From this database, 2,142 completed sleep disorder questions at their one‑year follow‑up and met study criteria. Participants were at least 16 years old, had moderate‑to‑severe TBI, were admitted to a specialized inpatient rehabilitation program within 72 hours of injury, and had height, weight, cognitive scores, and one‑year follow‑up data available. Participants were grouped as having no sleep disorder (84%), a pre‑existing sleep disorder (9%), or a new sleep disorder after TBI (7%).

How was the study conducted?

Sleep disorders: At the one‑year follow‑up, participants reported whether a doctor had diagnosed them with a sleep disorder and when it began, classifying them as having no sleep disorder, a pre‑existing disorder, or a new disorder after TBI. 

BMI (Body Mass Index): Height and weight was recorded at rehabilitation admission and self‑reported at one year, with standard categories for underweight, healthy weight, overweight, and obesity. 

Recovery outcomes: How well participants recovered was assessed at one year using the Extended Glasgow Outcome Scale (GOSE) for overall functioning and the FIM Cognitive subscale for thinking and communication abilities.

Mental health: Depression and anxiety were measured using the PHQ‑9 and GAD‑7 questionnaires. 

Statistical analyses used logistic and linear regression to examine relationships among BMI, sleep disorders, and recovery while controlling for demographic, injury, and health factors.

How can people use the results?

Individuals with TBI: Individuals with moderate‑to‑severe TBI should discuss sleep concerns with their doctor and request screening if they experience poor sleep or daytime fatigue. Maintaining a healthy weight and staying physically active, as approved by the care team, may reduce sleep problems and support recovery.

Families and caregivers: Sleep problems are common after TBI and can affect recovery. Caregivers can support healing by promoting consistent sleep routines, a restful sleep environment, and raising sleep concerns with the care team, along with encouraging healthy eating and light physical activity.

Clinicians: Routine screening for sleep disorders should be part of TBI care, especially for younger and overweight or obese patients. Early treatment, along with weight management guidance and referrals to sleep specialists, may improve cognitive and functional outcomes.

Researchers: Future research should use objective sleep and body composition measures, follow patients over time, and include control groups to better clarify relationships between weight, sleep, and TBI recovery.

Policymakers and healthcare systems: Findings support integrating sleep screening, sleep education, and lifestyle programs into standard TBI rehabilitation services.

Reference

Ding, K., Salter, A., Driver, S., Hammond, F. M., Dreer, L. E., Nakase-Richardson, R., & Bell, K. (2025). Body mass index and sleep disorders after moderate-to-severe traumatic brain injury – a national TBI model systems study. Brain Injury, 39(7), 571–578. https://doi.org/10.1080/02699052.2025.2454422

The contents of this quick review were developed under a grant from the National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR grant number 90DPKT0009). NIDILRR is a Center within the Administration for Community Living (ACL), Department of Health and Human Services (HHS). The contents of this quick review do not necessarily represent the policy of NIDILRR, ACL, HHS, and you should not assume endorsement by the Federal Government.

The content of this Quick Review was generated and edited using Claude and Microsoft Co-Pilot and was carefully reviewed and edited by experts to ensure accuracy.