Is nasal saline irrigation an effective treatment for allergic rhinitis?
Nasal saline irrigation reduces the severity of allergy symptoms for up to eight weeks vs. no treatment. It is uncertain if adding nasal saline to pharmacologic treatment further improves symptoms over pharmacologic treatment alone. It is also unclear whether there is any difference in symptom outcomes when comparing the use of nasal saline and intranasal corticosteroids. Nasal saline is well tolerated.1 (Strength of Recommendation: B, recommendation based on inconsistent or limited-quality patient-oriented evidence.)
Allergic rhinitis is an immunoglobulin E–mediated nasal hypersensitivity to allergens. It often presents as rhinorrhea, sneezing, and nasal itching and may include other symptoms such as conjunctivitis and ear pain or fullness. Patients with allergic rhinitis can also have impaired sleep and social interactions, leading to a decreased quality of life. The prevalence of allergic rhinitis in the United States currently varies between 10% and 30% for adults and up to 40% for children, making this a common condition encountered by the family physician.2
This Cochrane review included 14 studies with a total of 747 participants (seven randomized controlled trials [RCTs], 260 adults; seven RCTs, 487 children) from China, Italy, Thailand, Turkey, and the United States.1 All of the studies were parallel-group RCTs; only two studies were described as single-blinded and the remaining 12 were nonblinded. The volume of saline used in the studies varied from less than 5 mL per nostril per application to more than 60 mL per nostril per application. The type of saline varied as well, ranging from hypertonic to isotonic. Treatment duration was one to 12 weeks across the different comparisons.
Primary outcomes included disease severity as measured by patient-reported symptom scores, including the Total Nasal Symptom Score (a five-item questionnaire with each question graded none, mild, moderate, or severe to evaluate nasal congestion, rhinorrhea, nasal itching, sneezing, and difficulty sleeping), visual analog scales, and other symptom scores. Because the results were reported using a variety of scores, data were calculated as mean difference and standard deviation. When different scales were used, the authors reported the standardized mean difference (SMD). The included studies were of low- to very low-GRADE quality. Adverse effects were not consistently reported in the studies. Only four studies specifically stated in their methods that adverse effects would be reported. Of the 10 studies that mentioned adverse effects, six reported only the effects in the nasal saline irrigation group; three studies reported adverse effects in both arms; and in the remaining study, it was not clear which allocated group experienced the adverse effects.
A meta-analysis of six studies (N = 407, 85 adults and 322 children) found that nasal saline irrigation may improve symptom scores compared with no saline or pharmacologic treatment at up to four weeks (SMD = –1.3; 95% CI, –1.8 to –0.8) and at eight weeks (five RCTs; N = 167, 65 adults and 102 children; SMD = –1.4; 95% CI, –2.4 to –0.5). When comparing nasal saline irrigation added to pharmacologic treatment (i.e., oral antihistamines or intranasal corticosteroids) vs. the same pharmacologic treatment alone, no additional differences were demonstrated. Similarly, no differences in primary outcomes were noted when nasal saline irrigation was compared with intranasal corticosteroid therapy. Epistaxis was not reported with saline in any of the included trials.
Guidelines state that an intranasal corticosteroid alone or an intranasal corticosteroid and an intranasal antihistamine are recommended as first-line treatment for seasonal and perennial allergic rhinitis.3 For seasonal allergic rhinitis, an oral antihistamine may be used in combination with an intranasal corticosteroid, and use of either an oral antihistamine or a leukotriene receptor antagonist is recommended. For perennial allergic rhinitis, oral antihistamines are preferred to leukotriene receptor antagonists.3 (Strength of Recommendation: C, based on consensus, disease-oriented evidence, usual practice, expert opinion, or case series.)
The practice recommendations in this activity are available at http://www.cochrane.org/CD012597.