LAUSR

ABSTRACT Background Dysbiosis of oral microbiome causes chronic diseases including dental caries and periodontitis, which frequently affect older patient populations. Severely disabled individuals with impaired swallowing functions may require nutritional supply via nasogastric (NG) tubes, further impacting their oral condition and possibly microbial composition. However, little is known about the effect of NG tube on oral microbes and its potential ramification. Methods By using 16S rRNA amplicon sequencing, we characterized the tongue microbiome of 27 patients fed with NG tubes and 26 others fed orally. Results The microbial compositions of NG-tube and oral-feeding patients were substantially different, with more Gram-negative aerobes enriched in the presence of NG tube. Specifically, NG-tube patients presented more opportunistic pathogens like Pseudomonas and Corynebacterium associated with pneumonia and lower levels of commensal Streptococcus and Veillonella. Co-occurrence analysis further showed an inverse relationship between commensal and pathogenic species. Conclusion We present a systematic, high-throughput profiling of oral microbiome with regard to long-term NG tube feeding among the older patient population.