Influence of ambient temperature on the correlation between self-monitoring of blood glucose and plasma glucose values in diabetes management.

INTRODUCTION Self-monitoring of blood glucose (SMBG) helps patients with diabetes mellitus maintain glycemic control. However, few reports exist on whether ambient temperature can influence SMBG values. AIM To investigate the effect of ambient temperature on the association between SMBG and plasma glucose (PG) values. METHODS The study was conducted between 2003 and 2010 in diabetic patients (n=2777, male/female = 1216/1561, mean age = 60.5 ±13.6 years) for whom the measurements of SMBG and PG were performed simultaneously (66,197 samples were measured). SMBG and PG were both measured by enzyme methods. Correlation coefficients were determined between SMBG and PG values, and the differences between their values were compared based on the temperature. RESULTS SMBG and PG were closely correlated at each temperature. The PG-SMBG difference was smallest at an ambient temperature of 20°C, around which SMBG differed from PG with temperature; namely, the SMBG value decreased as the ambient temperature increased, while the SMBG value increased as the ambient temperature decreased. DISCUSSION The present data indicate that the ambient temperature can minimally but significantly influence SMBG values. Further studies about the relevance of these findings on patient self-care are warranted.