Pain tolerance and obstructive sleep apnea in the elderly

Objective: Patients with painful conditions often suffer from sleep disturbances. However, changes in sleep pattern per se could also influence pain tolerance. Untreated obstructive sleep apnea (OSA) causes major disturbances in sleep pattern. The aim of this study was to assess whether continuous positive airway pressure (CPAP) treatment in elderly patients with OSA would result in improved pain tolerance.

Design: Randomized, double-blind crossover study.

Setting: Geriatric sleep center based in Antoine Charial University Hospital (Lyon, France).

Participants: A total of 13 consecutive OSA patients aged 70 and older randomly assigned CPAP treatment (lowCPAP versus highCPAP). Eleven patients completed the study.

Measurements: Overnight sleep recording, electrical pain tolerance assessment, and visual analog scale for sleep quality were performed.

Results: Both low- and highCPAP treatment significantly improved respiratory parameters. However, compared with baseline, the electrical pain tolerance score was significantly enhanced (analgesic effect) only under highCPAP treatment (21.2 ± 10.9 versus 28.4 ± 16.0; P = .03).

Conclusion: The treatment of OSA with CPAP would have an analgesic effect. This would represent a unique outcome attributed to CPAP treatment. Given the high prevalence of both OSA and chronic pain conditions in the elderly; our findings could hold many implications for very large segments of the elderly population.