The Effect of Eight Weeks of Passive Heat Therapy on Mental Health, Sleep, and Chronic Pain in Persons with Spinal Cord Injury: A Pilot Study

Background/Objectives: Rates of depression, anxiety, sleep disturbances, and chronic pain are higher in people with spinal cord injury (SCI) compared with able-bodied individuals. Passive heat therapy (PHT), which raises core body temperature, may be an accessible therapeutic intervention. The effects of PHT on mental health, sleep, and pain in persons with SCI are unknown. Methods: We performed a time-controlled pre–post intervention pilot study in which ten veterans with chronic SCI underwent an 8-week supervised PHT intervention to raise oral temperature by 1 °C each session. Outcome measures were the 5-item Mental Health Inventory, Epworth Sleepiness Scale, and International Spinal Cord Injury Pain Extended Data Sets version 1.0. Results: There were no adverse events related to the intervention and nine out of ten participants completed all their intervention sessions. There was a reduction in pain intensity (p = 0.039) upon completing the intervention (from a median (IQR) of 2.0 (0.0, 3.5) to 1.0 (0.0, 4.5) on a 0–10 scale). However, there were no improvements in self-reported mental health or sleep outcomes (p > 0.339). Conclusions: This pilot study suggests that supervised repeated passive heat therapy may confer benefits for chronic pain in veterans with chronic SCI. Follow-up studies with larger sample sizes and more extensive sets of chronic pain outcomes are needed to confirm these findings.