The therapeutic efficacy of Bifidobacterium animalis subsp. lactis BB-12® in infant colic: A randomised, double blind, placebo-controlled trial

Abstract

Background: The pathogenesis of infant colic is poorly defined. Gut microbiota seems to be involved, supporting the potential therapeutic role of probiotics.

Aims: To assess the rate of infants with a reduction of ≥50% of mean daily crying duration after 28 days of intervention with the probiotic Bifidobacterium animalis subsp. lactis BB-12^® (BB-12). Secondary outcomes were daily number of crying episodes, sleeping time, number of bowel movements and stool consistency.

Methods: Randomized controlled trial (RCT) on otherwise healthy exclusively breastfed infants with infant colic randomly allocated to receive BB-12 (1 × 10⁹ CFU/day) or placebo for 28 days. Gut microbiota structure and butyrate, beta-defensin-2 (HBD-2), cathelicidin (LL-37), secretory IgA (sIgA) and faecal calprotectin levels were assessed.

Results: Eighty infants were randomised, 40/group. The rate of infants with reduction of ≥50% of mean daily crying duration was higher in infants treated with BB-12, starting from the end of 2nd week. No infant relapsed when treatment was stopped. The mean number of crying episodes decreased in both groups, but with a higher effect in BB-12 group (-4.7 ± 3.4 vs -2.3 ± 2.2, P < 0.05). Mean daily stool frequency decreased in both groups but the effect was significantly higher in the BB-12 group; stool consistency was similar between the two groups. An increase in Bifidobacterium abundance (with significant correlation with crying time reduction), butyrate and HBD-2, LL-37, sIgA levels associated with a decrease in faecal calprotectin level were observed in the BB-12 group.

Conclusions: Supplementation with BB-12 is effective in managing infant colic. The effect could derive from immune and non-immune mechanisms associated with a modulation of gut microbiota structure and function.

Figure 1

Panel (A). The design of the study. Panel (B). The flow of subjects during the phases of the study

Figure 2

Panel 1. The results of the main study outcome (ITT analysis): the rate of infants with reduction of ≥50% of duration of crying after 28 days of treatment. Eighty percent of the BB‐12 group and 32.5% of the placebo group showed a ≥50% reduction in crying duration after 28 days of treatment. The between‐group difference was significantly in favour of BB‐12 and the asterisk indicates a significant difference (* = BB‐12 vs placebo, P < 0.0001). Panel 2. The mean number of crying episodes during the week before treatment (V0‐V1, blue bars) and during the last week of treatment (V4‐V5, light blue bars) in infants enrolled in the two study groups. Values are expressed as mean and SD and symbols indicate a significant difference (* = BB‐12 V0‐V1 vs BB‐12 V4‐V5, P < 0.05; ** = BB‐12 V4‐V5 vs Placebo V4‐V5, P < 0.05; ° = Placebo V0‐V1 vs Placebo V4‐V5, P < 0.05)

Figure 3

Panel 1. The values of innate and acquired immunity biomarkers, calprotectin and butyrate faecal levels at baseline during the week before treatment (V0‐V1, blue bars) and during the last week of treatment (V4‐V5, light blue bars) in the two study groups. Panel A: human β‐defensin 2; panel B: cathelecidin (LL‐37); panel C: secretory IgA; panel D: butyrate; panel E: calprotectin. Values are expressed as mean and SD and asterisks indicate a significant difference (* = P < 0.05). Panel 2. The k‐means clustering (k = 2) of subjects based on the variation (V5‐V1) of the crying time, beta‐defensin 2, LL‐37, sIgA, butyrate, faecal calprotectin levels after 28 days of treatment. Cluster 1 (yellow dot) included 10% of infants enrolled in the BB‐12 group and 67% of infants enrolled in the placebo group. Whereas, Cluster 2 (blue dot) included 90% and 33% of BB‐12 and placebo subjects respectively. Panel 3. The boxplots showing the variation (V5‐V1) of crying time (in minutes), beta‐defensin 2, LL‐37, sIgA, butyrate and faecal calprotectin levels in subjects classified in Cluster 1 or 2. Boxes represent the interquartile range (IQR) between the first and third quartiles, and the line inside represents the median (2nd quartile). Whiskers denote the lowest and the highest values within 1.5 × IQR from the first and third quartiles respectively. Asterisks indicate a significant difference as obtained by pairwise Wilcoxon test (P < 0.05)

Figure 4

Linear regression of the duration of crying in minutes (V5‐V1) as a function of the abundance of Bifidobacterium (V5‐V1) (P < 0.05)