If you are wondering what these abbreviations are, allow me. I am here comparing three blood glucose-monitoring systems; this is my take on the ones currently available in India and by no means is influenced or biased since I paid for all of them myself from my own hard earned money. 😉 Besides, I also went a bit haywire with my food and schedule intentionally to see how the readings moved with various systems.
The three that I am comparing here are Medtronic’s Enlite, Abbott’s Freestyle Libre Pro and Accu-Chek Active. My idea of writing this blog is not to get too technical since sufficient reference material is now easily available online, so please search for the terms or write a comment below and I will be more than happy to explain. However, for the basics of understanding the three vary as follows.
Medtronic’s Enlite is a real-time Continuous Glucose Monitoring (CGM) system, it takes an interstitial reading every 5 minutes and transfers it through a transmitter attached to the sensor to the insulin pump and shows a real-time value plus graph of how blood sugars are moving. The insulin pump could even action a low glucose suspend or warn when the blood sugars are moving too rapidly in either direction. CGM systems also need to be calibrated at least once every 12 hours, so the fingerstick reading isn’t eliminated completely yet.
Abbott Libre Pro is a Flash Glucose Monitoring (FGM) system, it takes an interstitial reading every 15 minutes and you need a flash reader to read the blood glucose. Requires no calibration so no need to prick the fingers anymore, just flash the reader and voila! unfortunately Abbott has only made available the Pro version in India, for which you need to go to the Doctor every time to download the entire trend, all readings at a go. So, the finger pricking needs to still continue here or at least until Abbott launches the consumer version (FreeStyle Libre, no Pro) in the market. Also, this is an independent system that does not crosstalk with insulin pumps, at least not yet.
Accu-Chek Active (Fingerstick) is the conventional system where we take a small blood sample mostly by pricking our finger tips on to a strip inserted in the Glucometer for a spot reading. Now most of us are acquainted with this as we have been using this at rhymes home since decades already so I will spare you from more details.
I usually check my blood glucose using the Fingerstick method at least 6 times a day- fasting, before lunch, postprandial, before exercise, before dinner and at bedtime. For ease of comparison, I am going to take it at an average of 7 pricks a day! (I know, its probably more often than I drink water.)
Diving straight into my experiences as a user of all 3 systems simultaneously, here we go… but if this bores you at anytime please feel free to jump straight to the conclusion at the bottom.
As Indians, one of the most important criteria is value for money since we as ‘people with diabetes’ despite paying higher premiums do not get any insurance reimbursements, appropriate tax write-offs or government funding/incentive to manage our health better using the latest and best technologies available
to us from across the world. Of the three systems and depending on the Fingersticks done each day, it still is the Fingerstick method that might seem more economical to use but this isn’t an apple-to-apple comparison.
We are comparing say 7 readings with Fingerstick method to 96 readings with FGM to 288 readings with CGM a day. (Though I have many a times been able to extend the CGM to work beyond its prescribed 6 days, sometimes even able to stretch it beyond 14 days.)
A far cry I would say, in the number of readings, although 288 readings a day might seem a bit too many unless it has a specific purpose to it, I would be quite happy with the 96 readings since it then keeps the current FGM device active and accurate for 14 days instead of the official 6 days with CGM. Again the number of readings viz. 1728 on CGM is still much higher than 1344 on FGM through the life of both sensors.
Talking about number of days, Libre was affixed on my triceps (arm, as it has only been passed/recommended to be fixed on the arm currently) stayed on quite relentlessly for all 14 days and beyond despite of me testing it thoroughly in the Gym and with multiple showers on Gym days too.
For me, the skin around it had turned itchy from 7th day onwards. I have sensitive skin so don’t take this to heart, I checked with a few friends who too had tried the Libre and they did not have any similar issues. Enlite, however, had to be reinforced with multiple overtapes to keep it in place on my Abs, which still failed on the 9th day.
A fun experience in the Gym was that since the Libre was visible on my arm, other people in the Gym enquired what it was and a few even wanted it as they thought it looked quite cool. Although the Enlite remains hidden under the vest (it can be fixed on triceps/arms or anywhere you may think it works best for you) and my experience with it the previous times too, training the body part where the sensor was fixed threw the readings out of order or the sensor failed.
Now for the accuracy, which is the most critical part. There is still no contest between a reading taken from blood glucose and interstitial fluid as I noticed some lags in both CGM and FGM readings. The readings taken through interstitial fluid which surrounds the cells of the tissue below the skin, and usually glucose moves from blood vessels and capillaries first and then into the interstitial fluid so the reading from Fingerstick will always be ahead. Although I was quite impressed with the results I was getting from the Libre Pro, being more accurate and with a shorter lag as compared to Enlite.
Irony is that the readings from interstitial fuilds across different parts of the body vary and that is where I feel that some benefit of doubt goes in favour of Libre. It is known that the insulin absorption is most rapid into the abdomen followed by arms, then the legs and finally the buttocks. And the sequence and speed of blood flowing to these regions vary as well.
Ease of applicability and pain, Libre takes the cake here, as there was virtually no pain. I did not even feel or remember a sensor was sticking to my arm unless it drew some attention. 😉 And fixing it was a breeze too. In comparison the Enlite that takes around 10 minutes of careful application to two hours of warm up before it starts picking the trend, the Libre starts giving the readings after one hour of quick fixing.
Although, the most unfair part here is that the CGM was real-time and I could see the readings all the time on my insulin pump but since the Libre Pro’s reader was only with the doctor and unless I ran to the doctor every 15 minutes for a reading (I’m not joking), I was perceivably blind for the entire period this was on my body.
Insulin pump could also take notes of the meals, activities, fingersticks, insulin doses, etc. and shows full analytics using the Medtronic software. Whereas for the Libre Pro, it had to be manually noted (either on paper or third-party Apps) and painstakingly correlated with the sensor glucose trend instead.
I am lucky to have a doctor and friend who sits across to discuss the graphs and suggests corrections to my basal sets but I have heard of many horror stories where people with diabetes did fix the Libre Pro and then downloaded the results after 15 days to barely even get a proper 10 minutes discussion of any value from the results, which is deterring to say that many first time users might also be last time users.
Though each has its own advantages and disadvantages at this stage, I think there will be better devices and better solutions coming soon. I am also a big believer of economies of scale making newer and better technologies cheaper and more accessible over time and hence the device of preference here ought to be the FGM since it eradicates the need of pricks completely and the number of readings being more than enough for daily consumption in comparison to the CGM or painful pricks otherwise making the fingers sore.
In a few years from now, and unless a cure for diabetes is available, I don’t think that people will really need to prick their fingers as a reader in the smartphone or wristwatch communicating with an almost invisible sensor affixed somewhere on the body will constantly tell us our blood glucose readings, carbs consumed, activities done, etc. altogether with insightful analytics… let’s hope its fewer than a few years!
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