A Michigan State University investigator is preparing to expand on an encouraging pilot study that used a music-listening intervention to influence chemotherapy-induced nausea.
Music-listening interventions (MLIs) are a form of complementary and integrative treatment that medical professionals may be unaware of. However, my colleagues at the Michigan State University College of Nursing and I are tackling research that suggests music—a fixture in many people’s daily lives—may possess a nausea-reducing capability.
MLIs have already shown considerable effectiveness in managing other symptoms. For example, the National Comprehensive Cancer Network has labeled music as an acceptable treatment modality to treat anticipatory nausea and vomiting related to chemotherapy, so long as the music is prescribed in conjunction with typical pharmaceuticals.1 Furthermore, the American Pain Society and the American Society of Regional Anesthesia and Pain Medicine have both endorsed music for its mitigating effects in the setting of postoperative pain.2 In addition, the c linical practice guidelines provided by the Society for Integrative Oncology also endorse music for patients with breast cancer in the setting of anxiety, mood disturbances, and pain.3
In all cases, these endorsements came as a result of careful review of the evidence base for MLIs. If pain, anxiety, and mood all can be positively impacted through the incorporation of an MLI—why not chemotherapy-induced nausea?
This research began with a systematic review of the available literature, scouring databases for all prior studies that examined an MLI as treatment for chemotherapy-induced nausea.
This search identified 10 relevant studies across the past 30 years. However, they had a variety of designs, making comparisons between them difficult. Some studies paired music with other interventions, which made it difficult to discriminate what percentage each intervention was contributing to nausea reduction. Variations in timing (when the MLI was delivered and when the effect on nausea was measured) also raised questions.
Moreover, in the world of pharmaceuticals, a drug’s half-life determines how quickly its effects fade. However, variations in how MLIs were timed to intervene on nausea illuminated the fact that MLI’s half-lives are not well understood. It remains unclear whether half-lives even exist for MLIs. Overall, the overarching body of existing literature highlighted a need for more nuanced research.
The greatest uncertainty that remains with MLIs has to do with mechanism of action. Although MLIs have previously demonstrated the potential to relieve nausea, investigators do not yet understand how the brain physiology permits this.
One possible answer to this question comes from surprising research unrelated to chemotherapy-induced nausea. In 2000, Evers and Suhr4 published a study in which healthy participants listened to music that participants rated as “pleasant” and music that participants identified as “unpleasant.” In this study, the concentration of serotonin in blood platelets was measured at baseline (before any music), after the unpleasant music, then after the pleasant music. The release of serotonin from platelets was significantly less after the pleasant music intervention than what was measured after the unpleasant music. These findings connected to chemotherapy-induced nausea by way of its serotonin effects. After chemotherapy, this neurotransmitter becomes a major contributor to the sensation of nausea. This also explains the pharmacologic rationale for prescribing drugs that antagonize serotonin’s ability to bind to receptors at the postsynapse of neurons in the central nervous system.5
This interesting physiologic possibility initiated a pilot study that yielded encouraging results. Twelve patients were asked to engage in a 30-minute MLI whenever they felt the need to take their antiemetic medication as needed, beginning on the day of chemotherapy administration and continuing through day 5. Participants used ordinal scales to rate their nausea severity and their distress level before the MLI and again immediately upon completion. Platelet serotonin levels were not drawn due to cost. In total, 66 MLIs were engaged at various points within the 5-day nausea window. The analysis showed a significant reduction in both nausea severity and patient distress, which is an encouraging finding in a pilot study and worth replicating in a larger randomized control trial.
This larger trial will have several refinements. First, a control group using a nonmusic intervention will reveal what percentage of the antinausea effect was attributable to the MLI and what percentage was attributable to medication alone. Creating study groups by time (5-minute MLI and 10-minute MLI) will allow subgroup analysis by dose, which is something not often done in MLI research. Finally, strict attention to competing auditory stimuli (other sounds in the room) through noise-cancelling headphones will help participants more fully engage with the MLI.
Strategically using music listening to produce improved physiologic states is not new, but its scientific activity is gaining momentum. Work in chemotherapy-related nausea may inspire other investigators to think about MLIs in the setting of other nausea forms, such as pregnancy-induced nausea or postoperative/postanesthesia nausea. As the research builds, the day may come when the oncology nurse delivers acetaminophen alongside 20 mg of Mozart.
References