Fatty acid levels in earwax could provide an objective marker for Ménière’s disease, according to early research examining the chemical composition of cerumen.
Ménière’s disease is a chronic inner ear disorder that can cause vertigo, hearing loss, tinnitus, and a feeling of pressure or fullness in the ear. Diagnosis is based largely on symptoms, hearing tests, and the exclusion of other conditions because no laboratory test can confirm the disease.
The Research Foundation for the State University of New York recently announced that a mass spectrometry-based earwax test is available for licensing. The technology remains at an early laboratory stage and has not been validated for clinical diagnosis. A US patent application is pending.
The approach is based on a 2023 pilot study published in ACS Omega. Researchers investigated whether earwax contains chemical patterns associated with Ménière’s disease.
The researchers analyzed samples using gas chromatography-mass spectrometry and direct analysis in real time-high-resolution mass spectrometry. The direct analysis method required little sample preparation and rapidly produced a broad chemical profile. Gas chromatography-mass spectrometry was then used to identify and measure individual compounds.
The study included earwax from 15 patients: seven without Ménière’s disease and eight with confirmed or tentative disease. Statistical modeling was conducted using six samples from each group.
Three fatty acids helped distinguish the groups: cis-9-hexadecenoic acid, cis-10-heptadecenoic acid, and cis-9-octadecenoic acid. All three were detected in patients with and without Ménière’s disease, but their concentrations were lower in samples from patients with the condition.
Targeted analysis used samples from nine patients without Ménière’s disease and six with the disease. Average concentrations of the three fatty acids were approximately 78 percent, 85 percent, and 58 percent lower, respectively, in the Ménière’s disease group.
The researchers also tested the classification model on three additional samples, which it categorized correctly. However, the model’s internal classification performance was described as modest, and three samples are insufficient to establish diagnostic accuracy.
The findings show that earwax may contain measurable biochemical information relevant to Ménière’s disease. Collection is minimally invasive, and mass spectrometry can detect small differences in its lipid composition. However, the results do not establish earwax analysis as a diagnostic test.
Larger, prospective studies must determine the method’s sensitivity and specificity, compare Ménière’s disease with other vestibular disorders, and assess how age, genetics, medication, diet, ear-cleaning practices, and sample collection affect fatty acid levels.
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