Frequent Cannabis Users Have Fewer Nasal Problems, Study Finds

Cannabis consumers have fewer sinonasal symptoms, such as nasal congestion or a runny nose, than non-consumers, according to a new study by researchers at the Keck School of Medicine of the University of Southern California.

Published in the journal JAMA Otolaryngology–Head & Neck Surgery, the study used data collected by the National Health and Nutrition Examination Survey (NHANES) to assess the association between cannabis use frequency and reports of sinonasal symptoms.

Investigating how cannabis affects sinonasal symptoms is important, the researchers say, as it should allow healthcare professionals to better counsel their patients on the possible health risks of smoking.

Sinonasal symptoms are less common in regular cannabis users

This study looked at data gathered from 2,269 adults between the ages of 20 and 69 who were respondents to the 2013-14 edition of the NHANES survey.

The NHANES survey includes questions on sinonasal symptoms as well as cannabis use frequency and the use of other substances, such as tobacco. The survey sample was designed to be nationally-representative, with selective oversampling of low-income and racial/ethnic minority groups in order to give results that are more generalizable to the US population.

Of the participants in this study, 75% reported having never used cannabis and 16% endorsed non-regular cannabis use, defined in this study as using cannabis less than 15 times in the past 30 days. The remaining 206 individuals all reported using cannabis regularly.

The researchers found that 45% of regular cannabis users reported having at least one sinonasal symptom. In comparison, nearly 65% of those who had never used the drug reported at least one symptom.

After adjusting for possible confounding factors such demographic characteristics, medical comorbidities, and any history of facial trauma, the researchers found that those who used cannabis regularly were 78% less likely to report sinonasal symptoms than never-users. No statistically significant association was seen between sinonasal symptoms and occasional cannabis users.

Nasal congestion was reported by more than 6-in-10 participants who had symptoms. The next most common symptom was a change in smell over the past 12 months, followed by a runny nose.

The differences between cannabis and tobacco

While cannabis users were significantly less likely to experience sinonasal symptoms, the researchers also found that tobacco cigarette smokers were twice as likely as non-smokers to report experiencing symptoms.

The contrast between cannabis users and tobacco smokers is intriguing. While the NHANES survey did not differentiate between different types of cannabis use, other recent surveys have determined that smoking is by far the most popular method of cannabis administration in the United States. If this pattern were to hold true for the current study, it would suggest that cannabis smoking may confer some kind of protective effect.

The researchers do emphasize that, due to the cross-sectional nature of the study, it is not possible to determine causality between cannabis use and the presence or absence of symptoms.

However, they also note the findings of several other studies which suggested that cannabis could address some of the pathophysiological elements related to nasal congestion. For example, CBD has been associated with time-dependent vasodilatory effects in humans, and this could lead to decreased mucosal swelling.

“This study does raise the question of whether there's some anti-inflammatory effect of cannabinoids,” Dr. Alfred Iloreta, an assistant professor of otolaryngology at Mount Sinai's Icahn School of Medicine in New York City, told United Press International. Iloreta was not involved in this study.

“I would not want people to take this study as saying you can cure yourself by smoking marijuana,” Iloreta said, adding that there are other established treatment options available. Iloreta advises that people with frequent symptoms talk to their doctor about treatment options such as medicated nasal sprays.

“Nasal irrigation, with devices like a neti pot, can work incredibly well,” he added.