Probiotics, calcium and acute diarrhea : a randomized trial in Indonesian children

Background Acute diarrhea and acute respiratory tract infections (ARTIs) continue to lead the infectious cause of morbidity and mortality among children <5 years of age in developing countries, including Indonesia. Efforts to prevent diarrheal disease by probiotics and milk calcium supplementation as alternative strategy are promising. We investigated the efficacy of calcium with or without two probiotic strains, tested independently, on incidence and duration of acute diarrhea and ARTIs among Indonesian children. In addition, cumulative duration and severity of diarrhea due to rotavirus or other causes, growth, and iron and zinc status were tested. The associations of food-hygiene practices with diarrhea prevalence in children were also determined. Methods We conducted a 6-month, double-blind, placebo-controlled trial. A total of 494 Indonesian healthy children aged 1 to 6 years randomly received low-lactose milk with low calcium content (LC; ∼50 mg/day; n = 124), regular calcium content (RC; ∼440 mg/day; n = 126), RC with 5.108 colony-forming units per day of Lactobacillus casei CRL 431 (casei; n = 120), or RC with 5.108 colony-forming units per day of Lactobacillus reuteri DSM 17938 (reuteri; n = 124). Incidence and duration of diarrhea were the primary outcomes. Secondary outcomes were incidence and duration of ARTIs, severity of diarrhea (modified Vesikari score and fecal osmolarity, calprotection and mucin), growth, and iron and zinc status. The cross-sectional association between food-hygiene practices and 7-day record period of diarrhea prevalence was assessed among 274 randomly selected children aged 12-59 months in a low socioeconomic urban area of Jatinegara sub-district of East Jakarta, Indonesia. Results Incidence of World Health Organization-defined diarrhea (≥3 loose/liquid stools in 24 hours) was not significantly different between RC and LC (relative risk 0.99; 95% confidence interval (CI): 0.62-1.58), between casei and RC (relative risk 1.21; 95% CI: 0.76-1.92), or between reuteri and RC (relative risk 0.76; 95% CI: 0.46-1.25) groups. Incidence of all reported diarrhea (≥2 loose/liquid stools in 24 hours) was significantly lower in the reuteri versus RC group (relative risk 0.68; 95% CI: 0.46-0.99). Irrespective of the definition used, reuteri significantly reduced diarrhea incidence in children with lower nutritional status (below-median height-and-weight-for-age z score). None of the interventions affected ARTIs. The mean total duration (131 children, 190 diarrheal episodes) was 1.35 days shorter in the reuteri group (relative risk 0.60; 95% CI: 0.36-0.99) in a 6-month period, likely by mainly affecting rotavirus-positive diarrhea. Rotavirus prevalence in diarrheal cases (30%) was not significantly different across the groups. None of the supplements affected diarrhea severity based on Vesikari score and fecal markers, except for a higher fecal mucin concentration in the casei group (P = .006). The increase in weight gain, weight-for-age z score (WAZ) changes and monthly weight and height velocities were significantly higher in the reuteri compared with RC group over 6 months period, whereas. L. casei, although giving less benefit, modestly improved weight velocity. Changes in underweight and stunting prevalence, anemia prevalence and iron and zinc status were similar among groups. No serious adverse events related to the interventions were reported. Children living in a house with clean sewage had a significantly lower diarrhea prevalence compared to those who did not have one or had dirty sewage (adjusted odds ratio 0.16; 95% CI: 0.03-0.73). The overall food-hygiene practice score was not significantly associated with diarrhea in the total group, but it was in children aged <2 years (adjusted odds ratio 4.55; 95% CI: 1.08-19.1). Conclusion L. reuteri may prevent diarrhea especially in children with lower nutritional status, reduce total duration of diarrheal episodes, and modestly improve growth over 6 months, but does not affect diarrhea severity. L. casei modestly improves monthly weight velocity, but does not reduce diarrhea incidence, duration or severity. However, it seems too early to recommend probiotics (e.g. L. reuteri) for routine use or for follow-up in public health programs to prevent diarrhea in children in developing countries. Milk calcium alone does not affect any of the outcomes. Moreover, none of the dietary treatments affect incidence and duration of ARTIs, and iron and zinc status in Indonesian children. In addition to other major determinants, poor mother’s food-hygiene practices contributes to the occurrence of diarrhea in Indonesian children <2 years.