2018 Section 6 - Laryngology, Voice Disorders, and Bronchoesophalogy

Gut microbiota

Figure 2 Comparison of α diversity in proton pump inhibitor (PPI) users and non-users, and in individuals with and without GI indications. Four metrics of α diversity were calculated on rare fi ed samples and one-tailed Wilcoxon rank sum tests carried out to test for signi fi cantly lower diversity with PPI use, or with GI indication. Signi fi cantly lower diversity was observed for all metrics in PPI users versus non-users (*); no difference was found splitting by GI indication (NS).

possible confounders including host genetics. We have demon- strated that PPI use is associated with an altered composition of the gut microbiota, and a moderately lower diversity. In all three analyses, the large observational study, between discordant twins, and the interventional replication, PPI use was associated with increases in the Lactobacillales order, and in particular the family Streptococcaceae. Further, we show these effects could result from downward movement of upper tract commensals. We observed a signi fi cant reduction in microbial diversity with PPIs. However, it was a small difference and became non-

signi fi cant after adjusting for covariates. This may be due to con- founding effects and/or reduced power of the smaller sample. Variables we found to associate with PPIs, such as BMI, frailty, and antibiotic use, are also known to reduce diversity. 24 26 40 Therefore, it is likely that these factors are partly responsible for the observed lower diversity in PPI users; such confounders were also not accounted for in previous observations of decreased diversity with PPI use. 32 This is further supported by a number of studies where no major changes in diversity have been observed. 28 30

Jackson MA, et al . Gut 2016; 65 :749 – 756. doi:10.1136/gutjnl-2015-310861

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