Body mass index and the acute hospitalization period considerations after traumatic spinal cord injury: A national...

Studies associating body mass index (BMI) and outcomes following traumatic spinal cord injury (TSCI) have focused on long-term prognosis. The implications of BMI during the acute hospitalization period remain unknown. This study aims to evaluate the associations of BMI with the need for spine surgery, the need for mechanical ventilation at discharge, and length of stay (LOS) to support better planning and risk stratification.

The Spinal Cord Injury Model System (SCIMS) was queried for adults (≥18) suffering TSCI. Patients were stratified by BMI category. A multinomial logistic regression assessed the association between BMI and outcomes (spinal surgery, mechanical ventilation, and LOS), controlling for patient and injury factors.

This study included 3773 patients (mean age 44.0 ± 18.0). Most underwent spinal surgery (81%) while 9.0% required mechanical ventilation. The mean LOS was 15.0 ± 19.4 days. Being underweight was associated with a small increase in spinal surgery (RRR = 1.01 [95% CI: 1.00, 1.02], P = 0.016). Underweight patients had a slightly higher likelihood of requiring mechanical ventilation (RRR = 1.02 [95% CI: 1.01, 1.03], P = 0.0006). Class III obesity was associated with a lower mechanical ventilation rate (RRR = 0.54 [95% CI: 0.35, 0.82], P = 0.0043). There was a positive correlation between BMI and LOS.

Differences were most evident at the extremes of BMI. Being underweight was associated with slightly higher rates of spinal surgery and mechanical ventilation, but a shorter LOS. At the other extreme, a higher BMI was associated with fewer patients requiring mechanical ventilation but with longer LOS than in patients with lower BMI. These findings suggest a complex impact of BMI on TSCI care. Ultimately, the contribution of BMI to acute hospitalization outcomes is likely small but is still an important consideration in patient care.