Can Type 2 Diabetes Sufferers Actually Estimate Serum Glucose Level From Interstitial Fluid Glucose Level: A Diabetes Patient’s Experience

INTRODUCTION: The general assumption is that blood glucose (BG) and interstitial fluid glucose (IntFG) are practically the same. We aimed to determine whether the typical patient with type 2 diabetes can use IntFG to estimate BG. DESCRIPTION: The study was conducted on an 83-year-old white male with type 2 diabetes. One hundred pairs of IntFG and BG observations mg/dL (n = 50 simultaneous; n = 50 with 15-minute lag) were made over a 10-day period. We used paired t tests, correlation coefficients, and linear regression to predict relationships between IntFG and BG. RESULTS: There were significant (P < .0001) mean differences between IntFG and BG (simultaneous: 53.8 mg/dL; 15-minute time lag: 46.4 mg/dL). There were significant (P < .0001) positive correlations between IntFG and BG (simultaneous: r = 0.641; 15-minute time lag: r = 0.712). Linear regression revealed that increased IntFG was significantly (P < .0001) associated with declines in mean predicted BG. CONCLUSION: The typical type 2 diabetes patient cannot use IntFG level to estimate BG.