R ecent studies have suggested that probiotics, via the gut-lung axis, may benefit asthma management by modulating immune responses and reducing inflammation.

In new research, Divya Balan, MD, and colleagues conducted a systematic review and meta-analysis evaluating the beneficial impact of probiotics on asthma. The findings, published in Allergy, Asthma & Clinical Immunology, highlight probiotics’ potential in managing asthma by reducing exacerbations and improving asthma control.

A total of 12 placebo-controlled randomized studies comprising 1,401 patients met the inclusion criteria. The criteria included patients diagnosed with bronchial asthma, studies involving the use of probiotics as an intervention, studies reporting relevant outcomes related to the efficacy and safety of probiotics in managing bronchial asthma, and studies published in any language with no restriction of publication date. The researchers observed various probiotic strains used in asthma treatment, with the most common from the probiotic Lactobacillus and Bifidobacterium genus. In one study, the findings showed fewer exacerbations in the probiotic group (23 of 212) compared with the placebo group (67 of 210); however, there were no differences in exacerbation duration (3.3 ±2.45 days and 3.3 ±2.5, respectively).

The meta-analysis indicated that probiotic supplementation was associated with improvements in asthma control. A pooled analysis from two studies with 63 patients revealed significant improvements in asthma test control scores (OR, 1.18; 95% CI, 1.18-3.64; P=0.001) following probiotic supplementation. Additionally, data on probiotic use showed improved fractional exhaled nitric oxide (FeNO) in one study, but pooled FeNO and eosinophil data were not statistically significant (P=0.46 and P=0.29, respectively). The researchers found no adverse drug reactions associated with probiotics as adjuvant therapy.

Dr. Balan and colleagues acknowledged that “there are not many studies on any specific probiotic strain for treating asthma from where we could have narrowed it down to a particular strain for the meta-analysis. Therefore, we warrant that more controlled trials are needed to investigate specific probiotic strains’ potential role in reducing asthma exacerbations and improving asthma control. The robust evidence in this area could find the place of probiotics adjuvant therapy in asthma management guidelines.”