Effectiveness of steam inhalation and nasal irrigation for chronic or recurrent sinus symptoms in primary care: a pragmatic randomized controlled trial

Background: Systematic reviews support saline nasal irrigation for chronic/recurrent sinus symptoms but the trials are small, and few in typical primary care settings. Steam inhalation is poorly evidence-based. Our aim was to estimate the impact of brief pragmatic interventions to use steam and nasal irrigation.Methods: Adults with a history of recurrent/chronic sinusitis and reporting significant impact on quality-of-life from 72 UK general practices, were randomised to four advice strategies by a practice nurse, using numbered opaque sealed envelopes: 1) usual care 2) steam inhalation daily 3) saline nasal irrigation daily supported by a demonstration video 4) Irrigation and steam inhalation. Results: 961 individuals consented. 871 returned baseline questionnaires (respectively n=210,n=219,n=232,n=210) and 671/871 (77%) participants self-reported Rhinosinusitis Disability Index (RSDI) scores at 3 months (the primary outcome). Multiple imputation avoided assuming data was missing completely at random. RSDI scores improved with both nasal irrigation and no irrigation (-7.4 and -5.2 respectively; adjusted estimate of the difference -2.51, 95% confidence intervals -4.65 to -0.37, p=0.021). By 6 months, significantly more patients maintained a 10 point clinically important improvement in the RSDI (44.1%, 36.6% respectively); fewer used over-the-counter (OTC) medications (59.4%, 68%) or intended to consult the doctor. Steam inhalation reduced headache but no other outcomes. There was no evidence of harms with either intervention. Interpretation: Steam inhalation for chronic sinus symptoms in primary care is not effective. A brief pragmatic intervention to encourage nasal irrigation is less effective than prior evidence suggests, but provides some symptomatic benefit, and empowers self- management. ISRCTN88204146