[The glycemic excursions in normal glucose tolerance individuals revealed by continuous glucose monitoring system].
Level 4 - case-series / case-control
Case series / single-arm prospective observational study without a control group
What was done
Continuous glucose monitoring system (CGMS) sensors were placed on 43 individuals with normal glucose tolerance (NGT) to measure glycemic fluctuations continuously for 72 ± 7 hours. Sensor accuracy was evaluated against plasma (n = 204) and capillary (n = 804) glucose measurements.
What was found
CGMS recorded 858 ± 77 glucose values per participant with a mean absolute difference of 8.9% ± 3.0%. CGMS readings correlated strongly with plasma (r = 0.93, P < 0.001) and capillary glucose (r = 0.95, P < 0.001). The mean daily glucose level was 5.3 mmol/L. Daily peak glucose was 7.8 ± 1.4 mmol/L (occurring 1–2 hours post-meal, highest after dinner) and nadir was 3.9 ± 0.7 mmol/L, with a difference between maximum and minimum of 3.9 ± 1.6 mmol/L. Excursions >7.8 mmol/L occurred in 63% (27/43) of participants, and brief excursions <2.8 mmol/L occurred in 21% (9/43). Daytime glucose stayed within 3.3–7.0 mmol/L for 95% of the time (range 74%–100%) and within 2.8–7.8 mmol/L for 99% of the time (range 87%–100%).
Why it matters
This study establishes reference CGM patterns in healthy adults, demonstrating that transient spikes >7.8 mmol/L and brief dips <2.8 mmol/L occur naturally in non-diabetic individuals.
Limits
The study is limited by a small sample size (n = 43), a short monitoring window (72 hours), and a single-arm observational design. Baseline participant characteristics, diet, and physical activity are not described in the abstract, and brief dips <2.8 mmol/L may reflect CGM sensor artifacts rather than true physiological hypoglycemia.
Cited by
- supports Eating a meal or substantial snack triggers an insulin response, causing blood glucose to rise and remain elevated for roughly 90 minutes to two hours before returning to baseline.