Safety and efficacy of cryotherapy on chronic rhinitis: a systematic review and meta-analysis

Background Chronic rhinitis is when the nasal passages become inflamed and irritated, causing symptoms like nasal congestion, runny nose, sneezing, and postnasal drip that last for at least 12 weeks. While various medical treatments are available for chronic rhinitis, studies have shown that patients often do not comply with the treatment or report that it is ineffective. Cryotherapy for the nasal mucosa is a surgical option that has shown promise for these patients, with acceptable side effects. Aim Our goal is to evaluate the existing literature regarding the effectiveness and safety of cryotherapy as a treatment for chronic rhinitis. Methods We searched four electronic databases for relevant studies. Data were extracted from the included studies after screening procedures. Using the random effect model, we calculated the pooled mean difference (MD) for our continuous outcomes and pooled proportions for categorical outcomes. The I2 test was used to detect heterogenicity. Randomized controlled trials (RCTs) were assessed for methodological quality using the Cochrane risk of bias assessment tool 2, while observational studies and single-arm studies were assessed using the National Institutes of Health's tools. Results Our study comprised 21 studies; eighteen were eligible for analysis, with 1663 patients with chronic rhinitis. All of our assessed outcomes showed improvement with cryotherapy from their baseline status. Our pooled MDs for Total Nasal Symptom Score (rTNSS), Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), and Nasal Obstruction Symptom Evaluation (NOSE) scores were as follows: ( - 3.58, 95% CI [ - 3.80, - 3.37], p < 0.001), ( - 1.48, 95% CI [ - 1.68, - 1.27], p < 0.001), and ( - 26.65, 95% CI [ - 33.98, - 19.31], p < 0.001), respectively. Regarding nasal obstruction and rhinorrhea, cryotherapy showed effectiveness in 61% and 52% of patients in the complete relief subgroup and 26% and 34% in the < 50%-relief subgroup, respectively. Conclusion We observed significant improvement in our measured outcomes as rTNSS, RQLQ, and NOSE scores compared to the baseline state, demonstrating the cryotherapy's efficacy. This improvement was consistent in all subsequent follow-up periods. However, we need more high-quality RCTs for stronger evidence to be generalized.