Serum Concentrations and Dietary Intake of Vitamin B12 in Children and Adolescents on Metformin: A Case-Control Study

The International Society of Pediatric and Adolescent Diabetes (ISPAD) recommends metformin (MET) use for metabolic disturbances and hyperglycemia, either in combination with insulin therapy or alone. A caveat of MET therapy has been suggested to be biochemical vitamin B₁₂ deficiency, as seen mainly in studies conducted in adults. In the present case-control study, children and adolescents of different weight status tiers on MET therapy for a median of 17 months formed the cases group (n = 23) and were compared with their peers not taking MET (n = 46). Anthropometry, dietary intake, and blood assays were recorded for both groups. MET group members were older, heavier, and taller compared with the controls, although BMI z-scores did not differ. In parallel, blood phosphorus and alkaline phosphatase (ALP) concentrations were lower in the MET group, whereas MCV, Δ₄-androstenedione, and DHEA-S were higher. No differences were observed in the HOMA-IR, SHBG, hemoglobin, HbA1c, vitamin B₁₂, or serum 25(OH)D₃ concentrations between groups. Among those on MET, 17.4% exhibited vitamin B₁₂ deficiency, whereas none of the controls had low vitamin B₁₂ concentrations. Participants on MET therapy consumed less energy concerning their requirements, less vitamin B₁₂, more carbohydrates (as a percentage of the energy intake), and fewer fats (including saturated and trans fats) compared with their peers not on MET. None of the children received oral nutrient supplements with vitamin B₁₂. The results suggest that, in children and adolescents on MET therapy, the dietary intake of vitamin B₁₂ is suboptimal, with the median coverage reaching 54% of the age- and sex-specific recommended daily allowance. This low dietary intake, paired with MET, may act synergistically in reducing the circulating vitamin B₁₂ concentrations. Thus, caution is required when prescribing MET in children and adolescents, and replacement is warranted.

Comparison of Clinical Efficacy and Safety of Metformin Sustained-Release Tablet (II) (Dulening) and Metformin Tablet (Glucophage) in Treatment of Type 2 Diabetes Mellitus

OBJECTIVES

This study investigated the clinical efficacy and safety of metformin hydrochloride sustained-release (SR) tablet (II) produced by Dulening and the original metformin hydrochloride tablet produced by Glucophage in the treatment of type 2 diabetes mellitus (T2DM).

METHODS

This randomized, open and parallel controlled clinical trial consecutively recruited a total of 886 patients with T2DM in 40 clinical centers between May 2016 and December 2018. These patients were randomly assigned to the Dulening group (n=446), in which patients were treated with Dulening metformin SR tablets, and the Glucophage group (n=440), in which patients were treated with Glucophage metformin tablets, for 16 weeks. The changes in the levels of glycated hemoglobin (HbAc1) and fasting blood glucose (FBG) as well as weight loss were compared between these two groups. Also, the overall incidence of adverse drug reactions (ADRs) and the incidence of ADR of the gastrointestinal system observed in patients of these two groups were also compared.

RESULTS

There were no significant differences in demographic and basal clinical characteristics between these two groups. The Dulening and Glucophage groups showed comparable levels of decrease in HbA1c levels, FBG and weight loss after 12-week treatment (all p>0.05). The Dulening group had a significantly lower overall incidence of ADRs as well as gastrointestinal ADR than the Glucophage group.

CONCLUSIONS

Metformin SR tablets (II) and the original metformin tablets exhibit similar therapeutic efficacy in the treatment of T2DM, but metformin SR tablets (II) has the significantly lower incidence of ADRs than the original metformin tablets.

Effects of body mass index or dosage on gastrointestinal disorders associated with extended-release metformin in type 2 diabetes: Sub-analysis of a Phase IV open-label trial in Chinese patients

AIM

To determine whether gastrointestinal (GI) tolerability of metformin monotherapy varies according to baseline BMI or at doses >1500mg/day in patients newly diagnosed with type 2 diabetes.

METHODS

We performed a sub-analysis of the safety population from a prospective, multicenter, Phase IV open-label study in which 371 Chinese patients with type 2 diabetes received extended-release metformin monotherapy for 16 weeks. The incidence, severity and duration of GI adverse events (AEs) were compared between normal-weight (BMI<25kg/m(2), n=155) and overweight/obese (BMI≥25kg/m(2), n=216) patients. The primary objective was to determine whether baseline BMI affect the incidence, severity and duration of GI AEs, using Fisher's exact test and Student's t-test. Secondary objectives were to compare these factors according to final metformin dose (≤1500mg/day versus 2000mg/day).

RESULTS

The proportion of patients who reported ≥1 GI AE did not differ significantly between BMI groups (25.2% of the normal-weight group versus 21.3% of the overweight/obese group; p=0.3840). Patients who reported GI AEs in the two BMI groups experienced similar GI AE severity (p=0.5410), mean duration (p=0.3572) and duration distribution (p=0.1347). There was no significant difference in GI AE severity and duration between metformin dosage groups (≤1500mg/day versus 2000mg/day).

CONCLUSIONS

Newly-diagnosed Chinese type 2 diabetes patients of normal weight are no more likely than overweight/obese patients to suffer from increased incidence rates, severity or duration of GI AEs when treated with first-line extended-release metformin monotherapy. Doses of 2000mg/day did not increase the severity or duration of GI AEs.