Blood Test Study Links Ear Protein Prestin to Tinnitus, With 50% Higher Levels

People with tinnitus had blood levels of an ear protein called prestin that were about 50 percent higher than those of people without the condition, according to a new study. ScienceAlert reported that the finding could be a step toward an objective test for tinnitus, but the protein is not yet reliable enough to diagnose it.

Tinnitus is the perception of persistent ringing or other phantom sounds. ScienceAlert says it is estimated to affect 15 percent of people globally. Today, doctors can diagnose it only if a patient reports hearing sounds that are not there.

How the prestin study was done

The study, published in the journal Otolaryngology – Head and Neck Surgery, involved 82 adults, half of whom had tinnitus. Researchers took blood tests and compared prestin concentrations between the two groups. The work builds on an earlier study by some of the same team.

Prestin is a motor protein in the membranes of outer hair cells lining the cochlea, the hearing organ of the inner ear. It helps amplify sound and is important for sensitive hearing. ScienceAlert noted that earlier research has tied prestin to hearing damage, and that its levels are influenced by noise exposure, age and hearing loss. Experimental models of hearing damage show the protein is altered by trauma, which suggests it could signal injury to the cochlea.

Otolaryngologist Kourosh Parham of the University of Connecticut said the results are proof-of-concept that an ear protein may play a central role in the development and management of tinnitus. He also said measuring prestin gives a clinical indication of how bad the tinnitus is.

What the study does not show

The researchers and ScienceAlert stress several limits. This was a small observational study, so it does not prove that high prestin levels cause tinnitus. The two are linked, and the researchers acknowledge that other factors probably contribute as well.

A separate diagnostic accuracy analysis found that, in this group of participants, the biomarker could not yet reliably diagnose tinnitus. The researchers suggest one possible reason: some participants may have had non-cochlear tinnitus, caused by something other than abnormalities in prestin. Future research may clarify that.

Why it matters for people with tinnitus

For now, nothing changes for patients. No blood test for tinnitus is available, and the study does not show that one is close. What it offers is a research lead: an objective, measurable signal in a condition that has so far depended entirely on self-report.

If the link holds up in larger studies, it could help build a diagnostic system for clinical settings. Parham said the work shows promise for using prestin as a biomarker and called it a first step toward developing drugs to help manage tinnitus. ScienceAlert described treatment as a possibility for the future, not something the study tested.

The cause of tinnitus has never been established with certainty, and the researchers do not claim to have settled it. The study points to the cochlea and one of its key proteins as a place to look more closely.

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Around Prague, based on reporting by ScienceAlert