Real-World Effectiveness and Safety of Hydrogen Inhalation in Chinese Patients with Type 2 Diabetes: A Single-Arm, Retrospective Study

AIM: To evaluate the real-life effectiveness and safety of Chinese patients with type 2 diabetes mellitus (T2DM) receiving hydrogen inhalation (HI) treatment as a supplementary treatment. METHODS: This retrospective, multicenter, observational 6-months clinical study included T2DM patients maintaining HI, visited at 4 time points. The primary outcome is the mean change in glycated hemoglobin (HbA1c) at the end of the study compared to baseline. The secondary outcome is analyzing the mean change of fasting plasma glucose (FPG), weight, lipid profile, insulin dose and homeostasis model assessment. Linear regression and logistics regression are applied to evaluate the effect of HI after the treatment. RESULTS: Of the 431 patients comprised, it is observed a significant decrease in HbA1c level (9.04±0.82% at baseline to 8.30±0.99% and 8.00±0.80% at the end, p<0.001), FPG (165.6±40.2 mg/dL at baseline to 157.1±36.3mg/dL and 143.6±32.3mg/dL at the end, p<0.001), weight (74.7±7.1kg at baseline to 74.8±10.0kg and 73.6±8.1kg at the end, p<0.001), insulin dose (49.3±10.8U/d at baseline to 46.7±8.0U/d and 45.2±8.7U/d, p<0.001). The individuals in subgroup with higher baseline HbA1c and longer daily HI time duration gain greater HbA1c decrease after 6 months. Linear regression shows that higher baseline HbA1c level and shorter diabetes duration are significantly in relation to greater HbA1c reduction. Logistics regression reveals that lower weight is associated with a higher possibility of reaching HbA1c<7%. The most common adverse event is hypoglycemia. CONCLUSION: HI therapy significantly improves glycemic control, weight, insulin dose, lipid metabolism, β-cell function and insulin resistance of patients with type 2 diabetes after 6 months. Higher baseline HbA1c level and shorter diabetes duration is related to greater clinical response to HI.