Theoretical framework:
Intestinal microbiota can have physiologic and pathologic effect on immune system. This population have many known and waiting to be known functions, Including: nutrition, protection and trophic effects on GI epithelium and immune system. Nutritional effects are helping in food digestion and producing short chain fatty acids, amino acids and vitamins. They promote carbohydrate break down and stabilize normal PH in gut lumen. Furthermore, probiotics can have barrier effects against alien microbes(13, 14). They colonize in gut lumen during first weeks of life and then produce anti-microbial substances like bacteroicins, and adhere to gastrointestinal epithelium, compete with pathogenic microbiota and impose high genomic burden on host. Gut microbiota overall have more than 100 times gene than our genome(15).
Diabetes mellitus type one, is an immune mediated disease and according to available evidence, patients in preclinical and clinical stage of disease have altered intestinal microbiota. For example, in preclinical stages, predominance of phylum bacteroidetes and on the other hand lack of butyrate- producing intestinal bacteria have been shown (16). Phylum firmicutes mainly produce butyrate in gut lumen. These two types of phyla are most abundant among intestinal microbiota. While butyrate is a short chain fatty acid and have many important immunomodulatory functions, lack of microbial population which mainly produce it may be a clue for such immune dysregulation in type one diabetes mellitus(17, 18). Some of butyrate functions are promoting regulatory T cells in gut and also enhancing intestinal epithelial cells ability in invading against pathogens(19, 20).
So while Intestinal microbiota and immune system can interact closely, probiotics and prebiotics must have important effects in human health. They promote mucin production, decrease intestinal permeability, and activate macrophages and enhancing phagocytic capacity. Also they increase antibody production in gut lumen especially IgA. production of cytokines and regulatory substances can maintain both immune system arms(14). Current evidence suggest prebiotics/ probiotics as promising novel preventive and treatment strategies(21). There is only one pilot study which administered three months multi-strain probiotic and found significant improvement in glycemic score and HbA1c(22). We aim to give symbiotic for 6 months and follow newly diagnosed diabetes type one children for at least one year.
Study design and setting:
This triple blind randomized placebo controlled clinical trial is carried out in endocrinology department of Akbar children’s medical center. This hospital is a tertiary medical center located in north-east of Iran, Mashhad. And is the biggest referral center of pediatric endocrinology and metabolism in East of Iran. It is affiliated with Mashhad University of Medical sciences.
Participants and recruitment:
At least one hundred thirty Children aged 6–18 years old with newly diagnosed diabetes type one participate in the trial. Diagnosis of type one DM is made as defined by International Society for Pediatric and Adolescent Diabetes (ISPAD) criteria(1). Study recruitment will be from inpatients and outpatient clinic of Akbar Hospital during March 2022 to March 2023. Patients who meet the inclusion criteria will enter the study.
Inclusion criteria:
Newly diagnosed children with type1diabetes mellitus aged between 6–18 years old.
Exclusion criteria:
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Presence of comorbid conditions like significant cardiac, hepatic or renal disease
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Presence of immunodeficiency
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Allergy to probiotics
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Patients not willing to participate in the study
Randomization and blinding:
The patients are randomly assigned to the intervention or control group. They are allocated in a 1:1 ratio to each group using a computerized research randomizer. The researchers are blinded to group assignments. All follow up data are collected by two researchers who are blinded to group assignments. The researchers who generate the randomization sequence are not involved in the treatment or future evaluation of the participants.
Intervention:
The intervention consists of administration of probiotics or placebo to newly diagnosed children with type 1 diabetes for a six month period. The placebo is quite similar in taste and appearance to the active product. Products are manufactured in the form of capsules and are supplied free of charge by ZIST TAKHMIR company, Iran. This company has no role in study concept and conduct and the analysis and interpretation of data. Participants are followed at 3 month intervals for one year. At each visit anthropometrical data, glycemic control and total dose of insulin required to keep the optimal glycemic control is evaluated and registered.
Control group:
Patients assigned to the control group will receive 3 month interval follow-up with standard medical care. The visits are quite similar to the intervention group.
Concomitant care:
Patients will continue to receive their usual care and follow up.
Patient and public involvement:
The study results will be presented as a research article and patients will also be informed of the results at the diabetes care unit and through an educational group in WhatsApp, while the study is finished.
Measures:
The main variable of the study are fasting c-peptide levels and HbA1c levels.
Secondary measures:
Insulin requirements (Unit/kg/day)
Anthropometric parameters (weight, height,BMI)
Occurrence of concomitant autoimmune diseases (celiac disease, hashimoto thyroiditis)
Complications like hypoglycemia or diabetic ketoacidosis during the study period.
Sample Size
The sample size was calculated according to sample size calculation formulas for studies that evaluate the effect of intervention. Due to lack of similar trials in type one diabetes mellitus, and considering researcher assumption which believe in 70% improvement in glycemic score with usual care and the minimum clinical effect size of 20% with this intervention, study population calculated to be 59 people. With estimation of 5% drop during intervention, 62 patients will be included in each group.
Statistical Analysis:
Statistical analysis will be performed using Spss statistical package version 22. Data will be presented using descriptive statistics including means, standard deviation and proportions. We will use students T test for quantitative data and chi-square test for qualitative data. Kolmogorov-Smirnov test will be used to test the normality of the independent variables. For all parameters level of significance in terms of P value would be 0.05.