I have a sinus infection.
And I have been thinking a lot about three conversations I have had recently about neti pots. One of them was with someone wholly un-skeptical, who assured me that he has fewer sinus infections since he started using the neti pot. I asked how he knew he was having fewer sinus infections or that it was specifically the neti pot which was preventing them. He gave me an uncertain look, and I dropped it (because I really hadn’t looked into neti pots myself and did not have much to offer by way of evidence for or against them, although my instinct was to be skeptical of their efficacy). The second conversation was with a fellow skeptic, who said she swears by them. Again, I did not have anything to offer the conversation, but moved neti pots up on my prioritized mental list of “Things that I need to research more deeply.” A few days ago, a fellow biologist who suffers from severe allergies also promoted the use of a neti pot for flushing out the sinuses.
So I set about to answer a couple of questions pertaining to neti pot usage:
What is the history of neti pot usage?
Is the use of a neti pot harmful, neutral or beneficial?
Is neti pot usage a valid therapy to prevent the occurrence of sinusitis (sinus infections)?
And to be honest, I was all ready to write up a post about how a true skeptic changes her mind when the evidence is compelling. I wanted to shout from the roof tops that I was initially wrong, but that I have educated myself and now understand! Instead, and I will reveal the punch line now, I remain unconvinced either way.
What is the history of neti pot usage?
My first stop was Wikipedia. Not by choice, but because it is invariably one of the top hits you get when searching for anything these days. Wikipedia was helpful in confirming the proper spelling of “neti” and (in addition to this awesome picture) provided me with additional search terms “saline nasal irrigation” and “nasal lavage.” Well, that sounded much less fruity to me, and I soon learned that the neti pot is just one of many tools for successful nasal irrigation. This technique is originally a Yogic and Ayurvedic treatment and describes the simple technique of pouring saline into one nostril and letting it run out through the other. Blech, but if it helps, I’m totally down to try it. So, if this technique has been floating around this long, AND has a fancy modern term to describe it, there must be LOADS of clinical research into the technique’s possible benefits… Eh, not so much.
I didn’t read much of the Wikipedia entry; instead, I scrolled to the bottom and looked through the list of references. Wikipedia cited some well known medical journals, some less well-known academic journals, and a few sketchy websites. A mixed bag of citations; not bad, but not great. Off to the literature for me.
Is saline nasal irrigation harmful, neutral or beneficial?
Almost every article I read attested to the safety of the treatment. Side effects, like a burning sensation or nasal irritation, are mild and rarely reported. One study had patients irrigating 2 to 6 times a day! It would appear that most studies agree that saline nasal irrigation is not harmful. Neutral or beneficial seems to be the key question…
Is it a valid therapy to prevent the occurrence of sinusitis (sinus infections)?
Side note: I have access to a library with institutional licensing for academic journals; if you do not, I highly recommend befriending someone who does. Everyone who calls themselves a skeptic needs to make an effort to read the primary literature whenever they can, otherwise you will always be dependent upon others’ interpretation.
So first I had to learn a bit about what a sinus infection is:
Healthy people’s respiratory tracts are protected from airborne contagion and debris by a mucociliary layer that lines the sinonasal cavity. This layer consists of columnar, ciliated epithelial cells and goblet cells bathed in mucus. Foreign particles are trapped in the sticky layer of mucus, and ciliary action propels the entire mucous layer out of the sinuses toward the nasopharynx. When this transport mechanism fails, rhinosinusitis occurs, usually in response to a virus, bacterium, irritant, or allergen.
Blech. Rhinosinusitis is near the top of the list of most common disorders for which antibiotics are prescribed, and perhaps over prescribed. Rhinosinusitis accounts for huge health care costs and a large loss in productivity due to missed days of school or work. It is a big problem that affects loads of people.
But somewhat surprisingly, there really isn’t a vast body of literature on the topic of nasal irrigation. The first problem with researching this technique is, how do you create a sham procedure to give to a control population? How do you fake shoving water up someone’s nose? Suggestions from the peanut gallery?
Therefore, the majority of studies assessing nasal irrigation have relied on qualitative data collected by interviewing patients on their perceptions of nasal irrigation usage and their self-reported changes in their symptoms. There are several types of questionnaires that get at quantifying the symptoms of rhinosinusitis and how they impact the patient’s quality of life; one of these is cheekily named the Sino-Nasal Outcome Test (SNOT20). I read several of these studies and was subjected to data such as one patient’s report that, “for me this is the magic cure for my sinuses.”Really, that was an honest example of the data collected by this study. Then I found a neat meta-analysis that analyzed these types of studies, choosing only those few that met rigorous design standards (maybe one day Lisa will talk about the pit-falls of the meta-analysis, but they have many merits). Long story short, their conclusions were that:
So, nasal irrigation with saline water makes people “feel” better. It leaves patients with the sense that their symptoms have improved, a finding that is supported by statistics. And there is some indication that using nasal irrigation translates to fewer days taking medication and few doctor visits. All very positive.
But what I really wanted to know is whether or not washing my nose with salt water prevents bugs and nasties from setting up house. What I was hoping to see was a comparison of two populations that suffer from chronic rhinosinusitis, one that used nasal irrigation and one that did not. Follow those groups for a couple years, and tell me if the group that is diligent about flushing water up their noses has fewer incidents of acute sinusitis attacks, after controlling for season, age, individual variation, etc. There was only one study that I found to be suggestive of the benefits of nasal irrigation, and interestingly, it was rejected from the meta-analysis because it was not a randomized controlled trial. This lone, not-yet replicated study showed that saline nasal irrigation reduced histamine concentrations in snot for up to 6 hours after treatment when compared to baseline histamine concentrations.Histamine concentrations are indicators of mast cell activation indicative of infection or inflammation. A very tenuous link between sinus health and nasal irrigation, but perhaps the first step in collecting some compelling evidence.
Now this little lit review I have done here is far from exhaustive, but for me, it was far from convincing. So, I won’t nay-say if someone tells me using their neti pot makes them feel better, evidence suggests that is absolutely true. However, neti pots as a “magic cure for my sinus,” I think not. For now, the technique requiring use multiple times a day just doesn’t seem worth the trouble (if you would like some not-yet-agreed-upon clinical guidelines, check out the Mayo Clinic or U. Wisconsin Department of Family Health). I’ll stick to using tissues and decongestants.