Fig. 1Scheme of the evaluation protocol. In protocol A, 10 patients and five patients underwent repetitive measurement of minimally invasive interstitial fluid extraction technology three and four times, respectively. Five patients in protocol A and all patients in protocol B underwent application of hydrogel patches before the evaluation for the purpose of the cleaning of skin surface. These patches for cleaning were not included in the analysis. CGM, continuous glucose monitoring.
Fig. 2Typical data of minimally invasive interstitial fluid extraction technology (MIET; solid black line) compared with data of continuous glucose monitoring (CGM; dotted line as the glucose profile and solid gray line as area under the curve from the glucose profile). (A) For protocol A and (B) for protocol B. SMBG, self-monitoring of blood glucose.
Fig. 3Correlation between area under the curve estimated by minimally invasive interstitial fluid extraction technology (MIET-AUC) and that calculated from continuous glucose monitoring profiles (CGM-AUC). Solid line indicates y=x.
Fig. 4Comparison of performance for extraction conditions: (A) change in glucose permeability and (B) that of minimally invasive interstitial fluid extraction technology (MIET) performance compared with continuous glucose monitoring (CGM) in repetitive measurements. Results are shown as the mean±standard deviation. AUC, area under the curve.
Fig. 5The influence of (A) glucose fluctuation and (B) average glucose levels on minimally invasive interstitial fluid extraction technology (MIET) performance. ΔCGM indicates the difference between the peak and the nadir values of continuous glucose monitoring (CGM) in the measurement period. AUC, area under the curve.
Fig. 6The results of a questionnaire about (A) pain at stamping and (B) impression regarding the hydrogel patch. With regards to the impression regarding the hydrogel patch, one patient experienced localized itching and, the other, vague discomfort.
Table 1Subject characteristics at baseline
Characteristic |
Value |
Age, yr |
57.8±15.0 |
Sex, male/female |
12/8 |
Body weight, kg |
62.4±11.1 |
Body mass index, kg/m2
|
24.0±3.4 |
Diabetes duration, yr |
11.5±11.1 |
Glycosylated hemoglobin, % |
8.9±2.3 |
Fasting plasma glucose, mg/dL |
114.4±20.0 |
eGFR, mL/min/1.73 m2
|
72.4±21.6 |
Urinary CPR, µg/day |
38.7±37.7 |
Type |
|
1 |
5 (25) |
2 |
15 (75) |
Treatment |
|
Oral hypoglycemic agent |
4 (20) |
Insulin |
16 (80) |