Common infectious diseases (CID) of the airways and the gastrointestinal tract are still a considerable cause of morbidity and mortality in elderly. The present study examined the beneficial effect of a dairy product containing the probiotic strainLactobacillus caseiDN-114 001 (fermented product) on the resistance of free-living elderly to CID. The study was multicentric, double blind and controlled, involving 1072 volunteers (median age = 76·0 years) randomised for consumption of either 200 g/d of fermented (n537) or control (non-fermented) dairy product (n535) for 3 months, followed by an additional 1 month's follow-up. The results showed that, when considering all CID, the fermented product significantly reduced the average duration per episode of CID (6·5v. 8 d in control group;P = 0·008) and the cumulative duration of CID (7v. 8 d in control group;P = 0·009). Reduction in both episode and cumulative durations was also significant for all upper respiratory tract infections (URTI;P < 0·001) and for rhinopharyngitis (P < 0·001). This was accompanied with an increase ofL. caseispecies in stools throughout the fermented product consumption (2–3·8 × 10⁷equivalents of colony-forming unit/g of stools,P < 0·001). The cumulative number of CID (primary outcome) was not different between groups nor was the CID severity, fever, pathogens' occurrence, medication, immune blood parameters and quality of life. The fermented product was safe and well tolerated. In conclusion, consumption of a fermented dairy product containing the probiotic strainL. caseiDN-114 001 in elderly was associated with a decreased duration of CID in comparison with the control group, especially for URTI such as rhinopharyngitis.

Objective: The risk of infection may be increased in people under stress such as shift workers. This study examined the effect of a fermented dairy product containing the probiotic Lactobacillus casei DN-114 001 (verum) on the incidence of respiratory and gastrointestinal common infectious diseases (CIDs) and on immune functions in healthy shift workers. Methods: The study was single-center, randomized, double-blind, and controlled. Volunteers received 200 g/day of verum (n = 500) or control product (n = 500) for 3 months; 1-month follow-up was carried out. Results: The cumulated number of CIDs (primary outcome) was not significantly different between groups. Because the Poisson distribution of the primary parameter did not fully fit the observed data, a post hoc categorical analysis was applied and showed a significantly lower cumulated number of CIDs in the verum group during the product consumption phase (odds ratio [OR] = 0.75, 95% confidence interval [CI] 0.59–0.95, p = 0.017). Verum also reduced the proportion of volunteers experiencing at least 1 CID (43% vs. 51%, p = 0.005), increased the time to the first occurrence of CID (p = 0.017) in the whole population, and reduced the cumulated number of CIDs in the subgroup of smokers (p = 0.033). In the course of CID, cumulated duration of fever was lower in the verum group (in the whole study phase) (p = 0.022), and an increase in leukocyte, neutrophil, and natural killer (NK) cell counts and activity (p = 0.047 to p < 0.001) was observed compared with control group. Verum was safe and well tolerated. Conclusion: The results indicate that daily consumption of a fermented dairy product containing Lactobacillus casei DN-114 001 could reduce the risk of common infections in stressed individuals such as shift workers.

Helicobacter pylori (Hp) eradication therapy alters gut microbiota, provoking gastrointestinal (GI) symptoms that could be improved by probiotics. The study aim was to assess the effect in Hp patients of a Test fermented milk containing yogurt and Lacticaseibacillus (L. paracasei CNCM I-1518 and I-3689, L. rhamnosus CNCM I-3690) strains on antibiotic associated diarrhea (AAD) (primary aim), GI-symptoms, gut microbiota, and metabolites. A randomised, double-blind, controlled trial was performed on 136 adults under 14-day Hp treatment, receiving the Test or Control product for 28 days. AAD and GI-symptoms were reported and feces analysed for relative and quantitative gut microbiome composition, short chain fatty acids (SCFA), and calprotectin concentrations, and viability of ingested strains. No effect of Test product was observed on AAD or GI-symptoms. Hp treatment induced a significant alteration in bacterial and fungal composition, a decrease of bacterial count and alpha-diversity, an increase of Candida and calprotectin, and a decrease of SCFA concentrations. Following Hp treatment, in the Test as compared to Control group, intra-subject beta-diversity distance from baseline was lower (p_adj = 0.02), some Enterobacteriaceae, including Escherichia-Shigella (p_adj = 0.0082) and Klebsiella (p_adj = 0.013), were less abundant, and concentrations of major SCFA (p = 0.035) and valerate (p = 0.045) were higher. Viable Lacticaseibacillus strains were detected during product consumption in feces. Results suggest that, in patients under Hp treatment, the consumption of a multi-strain fermented milk can induce a modest but significant faster recovery of the microbiota composition (beta-diversity) and of SCFA production and limit the increase of potentially pathogenic bacteria.

BACKGROUND: Helicobacter pylori ( Hp ) eradication therapy can alter gut microbiota, provoking gastro-intestinal (GI) symptoms that can be improved by probiotics. The effect on Hp patients of a Test fermented milk containing yogurt and three Lacticaseibacillus ( L. paracasei CNCM I-1518, CNCM I-3689, L. rhamnosus CNCM I-3690) strains was assessed on antibiotic associated diarrhea (AAD) (primary aim), GI-symptoms, gut microbiota composition and metabolites. In this aim, a randomized, double-blind, controlled trial was performed in 136 adults under Hp -treatment (14-day amoxicillin, clarithromycin, pantoprazole), who consumed the Test or a Control product for 28 days. Feces were analysed for gut microbiota composition, short chain fatty acids (SCFA), calprotectin, and viability of ingested strains. RESULTS: No effect of Test product was observed on AAD occurrence or duration, rating scores or number of days of GI symptoms. Hp -treatment induced a significant alteration in bacterial and fungal composition, a decrease of bacterial count and alpha-diversity, an increase of Candida and of calprotectin, and a decrease of SCFA concentration. Following Hp treatment, in the Test as compared to Control group, intra-subject beta-diversity distance from baseline was lower (p _adj =0.02), Escherichia-Shigella (p _adj =0.0082) and Klebsiella (p _adj = 0.013) were significantly less abundant, and concentrations of major SCFA (p=0.035) and valerate (p = 0.045) were higher. Viable Lp and Lr strains from the Test product were mainly detected during product consumption in feces. CONCLUSIONS: The study showed that 14-day Hp triple therapy alters gut bacterial and fungal community, their metabolites and gut inflammatory markers. Consumption of a multi-strain fermented milk can induce faster recovery of the microbiota composition and SCFA production and limit the bloom of pathobionts. (ClinicalTrials.gov, NCT02900196 ; First Posted : September 14, 2016; https://www.clinicaltrials.gov/ct2/show/NCT02900196 ).