Empathetic solicitude attenuates the affective and sensory dimensions of CO2-induced dyspnea: A randomized parallel arm experimental trial in healthy humans.

Dyspnea testifies to profound suffering in patients and its relief is a priority for caregivers. This can be achieved by correcting causative disorders ("etiopathogenic" approach) or targeting the dyspnea itself ("symptomatic" approach), as is done for pain. Empathetic solicitude from caregivers has an intrinsic analgesic effect, but its effects on dyspnea have not been formally documented. This study tests the hypothesis that the empathetic solicitude behavior of a caregiver during experimental induction of acute and intense dyspnea would have a mitigating effect. In a double-blind, randomized, controlled experimental trial, 80 healthy participants were assigned to a neutral behavior arm or a solicitude behavior arm. During two successive visits (V1 and V2), dyspnea was induced through CO2-rebreathing and (i) assessed in an immediate manner using 10 cm affective and sensory visual analog scales (A-VAS and S-VAS) and (ii) post hoc using the Multidimensional Dyspnea Profile (MDP). A-VAS ratings at the end of the dyspnea challenge were significantly lower at V2 in the "solicitude behavior" arm than in the "neutral behavior" arm (6.69 [3.825-9.67] vs. 8.05 [6.43-10], p = 0.039). There were no significant differences between arms regarding S-VAS. MDP analysis showed that CO2-rebreathing induced dyspnea of the air hunger type, with statistically significant reductions in its intensity and both the sensory and affective dimensions of dyspnea. This study shows that empathetic solicitude can reduce the affective and sensory dimensions of experimentally induced dyspnea in healthy volunteers. Future studies should evaluate the impact of empathetic solicitude on clinical dyspnea.