Meta-analysis on preventive and therapeutic effects of probiotic supplementation in infant atopic dermatitis

Despite a large body of research, the effect of probiotic administration on the incidence and severity of atopic dermatitis (AD) shows conflicting results. We aimed to investigate whether probiotic supplementation reduces the incidence and severity of AD. Three databases were systematically searched. A 22% lower incidence of AD was found in the probiotic group. The reduction in incidence was 49% when probiotics were given to pregnant and lactating mothers, and 27% when they were given to pregnant mothers and infants. A 39% reduction of AD incidence was achieved when administered to pregnant-breastfeeding mothers and infants. Significant differences in SCORAD (SCORing Atopic Dermatitis) favoring probiotics were observed, but the IDLQI remained unchanged. Lactobacillus (L.) rhamnosus was the most documented strain, but it turned out to be ineffective in reducing SCORAD. Conversely, L. paracasei and L. sakei showed a significant decrease in SCORAD. Probiotics are effective in the prevention of AD, but the effect is less conclusive for the treatment of AD, especially in infants <1 year. The intake of probiotics by breastfeeding mothers is an important measure and may become a novel preventive strategy. The preventive effect of probiotics against AD is not associated with family background or AD risk. L. paracasei and L. sakei show the greatest reduction in SCORAD.