BERLIN: Carried out by Dr. Katarina Braune from Charité – Universitaetsmedizin Berlin in Germany in collaboration with Professor Lutz Heinemann and the digital health company MedAngel BV, the new study set out to investigate how often insulin is stored by patients at temperatures that fall outside the manufacturer’s recommended range.
The researchers recruited 388 diabetes patients living in the USA and the EU and asked them to place MedAngel ONE temperature sensors either next to their insulin in the fridge and/or in their diabetes bag for insulin carried as a spare.
The sensors automatically measure the temperature every three minutes, which is up to 480 times a day, before sending the data to an app where it can be securely recorded. Temperatures were recorded for an average of 49 days.
After analyzing 400 temperature logs, including 230 for refrigerated insulin and 170 for carried insulin, the researchers found that 315 (79%) were stored at temperatures outside of the recommended temperature range.
On average, insulin stored in the fridge was out of the recommended temperature range 11% of the time, equivalent to 2 hours and 34 minutes per day, although insulin carried in diabetes bags was only outside temperature recommendations for around 8 minutes a day.
Even more importantly, 66 sensors (17%) measured freezing temperatures below 0ºC, equivalent to 3 hours a month on average.
The findings, presented at this year’s European Association for the Study of Diabetes (EASD) Annual Meeting in Berlin, Germany between 1 to 5 October, suggest that storing insulin in domestic fridges may be impacting quality. Many injectable drugs and vaccines are highly sensitive to heat and cold and can perish if their temperature changes even just a few degrees.
Insulin must stay between 2-8°C/36-46°F in the refrigerator or 2-30°C/30-86°F when carried.
“Many people with diabetes are unwittingly storing their insulin wrong because of fluctuating temperatures in domestic refrigerators,” says Dr. Braune.
“When storing your insulin in the fridge at home, always use a thermometer to check the temperature. Long-term storage conditions of insulin are known to have an impact on its blood-glucose lowering effect. For people living with insulin-dependent diabetes who take insulin several times a day via injections or continuously administer insulin with a pump, precise dosing is essential to achieve optimal therapeutic outcomes. Even gradual loss of potency introduces unnecessary variability in dosing. More research is needed to examine the extent to which temperature deviations during domestic storage affect insulin efficacy and patient outcomes.”