Improved Gastrointestinal Tolerance and Iron Status Via Probiotic Use in Iron Deficiency Anemia Patients Initiating Oral Iron Replacement

A total of 295 patients, with newly diagnosed iron deficiency anemia (IDA) who were planned to receive routine oral IRT were included in this prospective randomized non-placebo, controlled 3-month follow-up study. Patients were randomly assigned via simple randomization method to receive either iron replacement therapy (IRT) alone or IRT plus L. plantarum 299v probiotic support . Adult (aged older than18 years) treatment-naïve patients diagnosed with newly diagnosed IDA without previous IRT were included in the study, while those with irritable bowel syndrome, previous IRT therapy or intolerance to IRT and those with a known chronic disease (i.e., inflammatory bowel disease (IBD), celiac disease) or untreated active menometrorrhagia and hemorrhoid were excluded from the study.

All patients received IRT with ferrous sulfate (Fe2 + ) preparation (100 mg, once daily) for 3 months, while those in the IRT-Pro group also received daily (10B CFU) L. plantarum 299v probiotic supplementation for 30 days starting from the first day of IRT.

Data on gastrointestinal intolerance symptoms (loss of appetite, nausea, vomiting, abdominal pain, diarrhea, constipation and bloating) were recorded at three time points including baseline, within the first 30 days of IRT and at any time during 3-month IRT.

Serum hemoglobin levels (g/dL) and serum iron status markers including ferritin (ng/mL), iron (µg/dL), total iron binding capacity (TIBC, µg/dL) and transferrin saturation (%) were recorded at baseline and at 3 rd month of IRT. Data on treatment discontinuation were also recorded in study groups along with comparison of study variables in patients with vs. without treatment discontinuation within the first 30 days of IRT.

At least 189 patients were calculated to be included via sample size estimation (G*Power 3.1.9 program) based on a power of 80 % at a type I error of 0.05, and an effect size (w=0.261) calculated using data from a previous study by Cekin et al. .