Long-term effect of the Internet-based glucose monitoring system on HbA1c reduction and glucose stability: a 30-month follow-up study for diabetes management with a ubiquitous medical care system.

OBJECTIVE To investigate the long-term effectiveness of the Internet-based glucose monitoring system (IBGMS) on glucose control in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS We conducted a prospective, randomized, controlled trial in 80 patients with type 2 diabetes for 30 months. The intervention group was treated with the IBGMS, while the control group made conventional office visits only. HbA1c (A1C) was performed at 3-month intervals. For measuring of the stability of glucose control, the SD value of A1C levels for each subject was used as the A1C fluctuation index (HFI). RESULTS The mean A1C and HFI were significantly lower in the intervention group (n = 40) than in the control group (n = 40). (A1C [mean +/- SD] 6.9 +/- 0.9 vs. 7.5 +/- 1.0%, P = 0.009; HFI 0.47 +/- 0.23 vs. 0.78 +/- 0.51, P = 0.001; intervention versus control groups, respectively). Patients in the intervention group with a basal A1C >or=7% (n = 27) had markedly lower A1C levels than corresponding patients in the control group during the first 3 months and maintained more stable levels throughout the study (P = 0.022). Control patients with a basal A1C <7% (n = 15) showed the characteristic bimodal distribution of A1C levels, whereas the A1C levels in the intervention group remained stable throughout the study with low HFI. CONCLUSIONS Long-term use of the IBGMS has proven to be superior to conventional diabetes care systems based on office visits for controlling blood glucose and achieving glucose stability.