Assessment of postprandial hyperglycemia and circadian fluctuation of glucose concentrations in diabetic dogs using a flash glucose monitoring system

BACKGROUND: Postprandial hyperglycemia (PPH) and circadian glucose concentration fluctuations recorded in the home environment of dogs with naturally occurring diabetes mellitus (DM) have not been reported. OBJECTIVES: To determine if a flash glucose monitoring system (FGMS; FreeStyle Libre) can detect PPH and circadian fluctuations in glucose concentrations in dogs with variably controlled DM. ANIMALS: Fourteen client‐owned dogs with DM. METHODS: Prospective observational study. Interstitial glucose (IG) concentrations measured by the FGMS during a 13‐day study period were analyzed. RESULTS: A total of 17, 446 FGMS IG concentrations were analyzed. For all dogs analyzed together, median IG concentration measured within 30 (288 mg/dL), 60 (286 mg/dL), 90 (285 mg/dL), and 120 (285 mg/dL) minutes of meals was each significantly higher than the median IG concentration at all other times (260 mg/dL, 259 mg/dL, 258 mg/dL, and 257 mg/dL, respectively; range, 40‐500 mg/dL; P < .001 for each). Median night‐time IG concentration measured from all dogs on 3,547 samples recorded between 1:00 am and 6:00 am (268 mg/dL; range, 40‐500 mg/dL) was significantly higher than median IG measured on 13, 899 samples at all other time points (259 mg/dL; range, 40‐500 mg/dL; P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: The FGMS can be used for future studies of PPH and circadian fluctuations of glucose concentrations in dogs with DM in their home environment.