A study presented at the European Association for the Study of Diabetes found that patients are not storing their insulin at recommended temperatures.
The study, which studied 388 U.S and European diabetes patients, for an average of 49 days, revealed that 79 percent were not storing their insulin at the correct temperatures.
The storage temperature in the refrigerator was out of range 11 percent of the time, or about two hours and 34 minutes each day.
However, the patient's insulin only deviated from the recommended temperatures for about eight minutes each day, according to the study.
Sensors were used by the patients and placed next to their insulin in the refrigerator or in their diabetes bag and measured the temperature every three minutes, according to the study's authors.
"Long-term storage conditions of insulin are known to have an impact on its blood-glucose-lowering effect," the study stated. "These observational data showed that in a significant number of cases of insulin was exposed to temperatures outside the recommended range, especially when refrigerated. Thus, domestic refrigerators may pose an underestimated risk for insulin quality."
"The extent of how temperature deviations in storage affect insulin efficacy and patient outcomes needs further systematic investigation," the study's authors stated in their abstract.
Researchers for the study included Katarina Braune, Laura Kramer, Amin Zayani, Jeremias Weinstein and Lutz Heinemann.