Effect of Lactobacillus rhamnosus GG, LGG® and Bifidobacterium animalis subspecies lactis, BB-12®, on health-related quality of life in college students with upper respiratory infections

College students are susceptible to upper respiratory infections (URIs) due to inadequate sleep, psychological stress and close living quarters. Duration and severity of URI symptoms, and functional impairment, impact health-related quality of life (HRQL). Certain probiotic strains modulate immune function; and, may positively impact HRQL during URIs. This study assessed the effect of probiotics on HRQL outcomes (i.e., self-reported duration, symptom severity and functional impairment) during URIs in college students. Secondary outcomes included incidence of URIs, and missed school and work days due to URIs. The study was conducted January--May 2011. Subjects (N = 231) were college students living on-campus in residence halls at Framingham State University (Framingham, MA), and were randomized to receive placebo (n = 117) or probiotic-containing candy (1 billion CFU per gram Lactobacillus rhamnosus GG, LGGRTM, and Bifidobacterium animalis ssp lactis, BB-12RTM; n = 114) for 12 weeks. All subjects completed The Wisconsin Upper Respiratory Symptom Survey-21 to assess duration and severity (symptoms and functional status) of URIs and documented missed work/school days due to URIs. Between-group differences were analyzed using chi-square or Mann Whitney U test, and significance was set at p≤0.05. Final analysis included 198 subjects (Placebo, n = 97; Probiotics, n = 101). Median duration of URIs was significantly shorter by 2 days, and median severity score was significantly lower by 34% in the probiotics, compared to placebo, group. Incidence of URIs and missed work days were not different between groups; however, the probiotics group missed significantly fewer school days (mean difference = 0.2 days) compared to the placebo group. LGGRTM and BB-12RTM may be beneficial for mitigating decrements in HRQL, and minimizing missed school days, during URIs in college students. More research is warranted regarding mechanisms of action associated with these findings and the cost-benefit of prophylactic supplementation.