Author, date and country | Patient group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
---|---|---|---|---|---|
Wenus et al 2008 Norway | All adult inpatients that were prescribed antibiotics of at least 7 days duration were randomised to recieve a probiotic milk drink or placebo. | Randomised, double-blind, placebo-controlled study. | Primary end point criterion was diarrhoea, defined as at least three fluid stools/day for at least 2 days during the test period | 87 patients were randomized to probiotic (n=46) or placebo (n=41) treatment. Eight (27.6%) patients in the placebo group, and two (5.9%) patients in the probiotic group experienced AAD (P=0.035). | Small sample size High drop out rate (12 in each group). Calculations based on per-protocol analysis and not intention-to-treat. |
Koning CJ et al, 2008 Netherlands | 41 healthy volunteers were given 500 mg amoxycillin twice daily for 7 days and were randomized to either 5 g of a multispecies probiotic, Ecologic, or placebo, twice daily for 14 days. | Randomised, double-blind, placebo-controlled study. | Main outcome measures were intestinal microbiota composition, bowel frequency and consistency according to the Bristol stool scale | Bowel movements with a frequency >or=3 per day for at least 2 days and/or a consistency >or=5 for at least 2 days were reported less frequently in the probiotic compared to the placebo group (48%vs 79%, P < 0.05) | The use of healthy volunteers may not make this study transferable to those acutely unwell. Small sample size. |
Beausoleil et al, 2007 Canada | All hospitalized patients, who were anticipated to take at least three days of any systemic antibiotic, were randomly assigned to receive either a lactobacilli-fermented milk or a placebo. | Randomised, double-blind, placebo-control study. | The primary outcome of the present study was the incidence of AAD during the study period | Among 89 randomized patients, antibiotic-associated diarrhea occurred in seven of 44 patients (15.9%) in the lactobacilli group and in 16 of 45 patients (35.6%) in the placebo group (OR 0.34, 95% CI 0.125 to 0.944; P=0.05). | Hugely underpowered. Large proportion excluded (1306 of 1422 screened). Lack of generalisability of subjects as all hospitalised. |
Hickson et al, 2007 UK | 135 hospitalised patients taking antibiotics randomised to receive either probiotic drink or placebo. | Randomised, double-blind, placebo-controlled study. | Primary outcome: occurrence of AAD. Secondary outcome: presence of CDAD | 7/57 (12%) of the probiotic group developed diarrhoea associated with antibiotic use compared with 19/56 (34%) in the placebo group (p=0.007). No one in the probiotic group and 9/53 (17%) in the placebo group had diarrhoea caused by CDAD (p=0.001) | Analysis did not follow the intention to treat model. High exclusion rate (1625/1760) questioning generalisability. High numbers (16%) lost to follow up. |
Can M et al, 2006 Turkey | 151 inpatients randomised to recieve antibiotics plus either S. boulardii or placebo | Randomised, double-blind, placebo-controlled study. | Rate of AAD in both groups | The rate of AAD was 9% in the placebo group and 1.4% in the S. boulardii group (p<0.05) | Outcome measures not defined. No power calculation performed. No consort diagram. No intention to treat model. |
Cremonini et al, 2002 Italy | 7 randomised, control studies that included 881 patients. | Meta-analysis | Whether probiotics reduce AAD | Three studies showed significantly less AAD with a combined relative risk of 0.397 (95% CI 0.275 to 0.571) | Studies included children Poor homogeneity |
Thomas MR et al, 2001 USA | 302 hospitalised patients recieving antibiotics were randomly allocated to receive Lactobacillus GG or placebo for 14 days. | Prospective, randomised, double-blind, placebo-controlled trial. | Proportion of patients who developed diarrhoea | ADD occurrence rate was 39/133 (29.3%) in those receiving Lactobacillus and 40/134 (29.9%) in those receiving placebo (p=0.93) | Only abstract available from publishers. |