Possible Link Between Marijuana Use, Tinnitus

Study added to conflicting information on the issue

by Charles Bankhead,

NEW ORLEANS -- Self-reported monthly or more frequent marijuana use had a significant association with tinnitus, according to a retrospective analysis of a national database.

Marijuana users were almost 20 times more likely to report having tinnitus within the past month as compared with nonusers. An extensive multivariable analysis confirmed marijuana use at least once a month as an independent predictor of tinnitus, as reported here at the American Academy of Otolaryngology-Head and Neck Surgery Foundation meeting.

"The findings do not suggest marijuana alleviates tinnitus," said Z. Jason Qian, MD, of Stanford University in California. "In fact, the findings suggest that marijuana use may be associated with prevalent tinnitus, but no dose response was observed. The study is in line with animal studies that suggest cannabinoids may increase tinnitus."

Research into the relationship between tinnitus and marijuana use has produced mixed results.

A preclinical study conducted almost a decade ago suggested a potential role for marijuana in treating tinnitus. Proponents of medical marijuana for treating tinnitus have cited the study in making their case. A case report of a patient with longstanding idiopathic intracranial hypertension documented resolution of symptoms, including tinnitus, following treatment with the synthetic cannabis compound dronabinol.

On the other hand, a laboratory study suggested that cannabinoid receptor agonists exacerbated a preclinical model of tinnitus. A just-published literature review found limited support for therapeutic effects of cannabis in otolaryngology, none involving tinnitus. Authors of another recent review came to a similar conclusion.

Seeking more insight into the relationship between marijuana use and tinnitus, Qian and colleagues analyzed data from the 2011-2012 National Health and Nutrition Evaluation Survey (NHANES). They identified 1,582 adults who had audiometric testing and who completed questions that elicited information about hearing, drug use, current health status, and medical history.

Specifically, participants were asked whether they had symptoms of tinnitus lasting 5 minutes or longer within the previous 12 months and whether they had smoked marijuana one or more times a month for the past 12 months. Responses showed that 499 participants met the tinnitus criteria and 118 met the marijuana use criteria.

A univariate analysis showed that marijuana was the only substance use associated with tinnitus (HR 19.41, P<0 .001="" 12="" a="" alcohol="" along="" an="" analysis="" and="" association="" cocaine="" did="" each="" episodes="" factors:="" for="" have="" heroin="" in="" independent="" marijuana="" methamphetamine="" monthly="" months="" more="" multivariable="" not="" of="" one="" or="" other="" p="" past="" predictor="" previous="" remained="" several="" significant="" the="" times="" tinnitus.="" tinnitus="" use="" with="" within="">

• Marijuana use - HR 1.75, (95% CI 1.02-3.01)

• Autonomic hearing loss - HR 2.90 (95% CI 1.78-4.72)

• Work noise exposure - HR 1.69 (95% CI 1.12-2.55)

• Depression - HR 2.28 (95% CI 1.30-4.03)

• Anxiety - HR 2.48 (95% CI 1.42-4.36)

Neither frequency or quantity of marijuana use nor tinnitus frequency or severity significantly influenced the association between marijuana use and tinnitus.

Qian acknowledged limitations of the study: no standardization of the marijuana product; reliance on answers to available questions from the NHANES questionnaires, which likely did not ascertain psychosocial covariables; and the limitations inherent to a cross-sectional study, which preclude inferences on causation.

Data for the analysis came from a period before many states' legislatures had taken action to make marijuana and related products more widely available. As a result, much of the marijuana use identified in the study might have involved illegal behavior.

"Do you think the illegality introduces any confounding factors?" asked Daniel H. Jung, MD, PhD, of Massachusetts Eye and Ear in Boston.

The analysis did not identify a similar association with alcohol use or other types of illicit drugs, suggesting that illegal behavior was not a confounder, Qian responded.

A study conducted by the Substance Abuse and Mental Health Services Administration showed associations between several types of illicit drug use, including marijuana, and various health conditions. Marijuana use was not associated with tinnitus but use of hallucinogens and inhalants was.