I recently read a rather interesting paper about the fairly recent technological advance in diabetes management being coined the ‘Artificial Pancreas’ or AP for short. The first thing to say about this is that I feel the name is somewhat misleading. To me, this suggests that the system simply replaces the human pancreas and behaves in the same way…no no no this is not quite the case. I am not being negative, it does replicate the organ in many ways however, no entirely.
Confused? Sorry – let me explain!
The AP works like the human pancreas in terms of basal insulin. Essentially, it is an insulin pump, connected to a CGM (nothing new I hear you say!) but the difference is that the pump and CGM talk to each other and the pump adjusts its actions according to the results being fed to it by the CGM. The only thing you have to do is bolus according to what you have eaten – as usual.
The study that I read was based on children but was very interesting and I’m sure the same findings could also be applied to adults.
The over-riding conclusion was that the AP was very effective in reducing the incidence of hypoglycaemia compared to the use of a sensor augmented pump particularly overnight. This outcome was coupled with a reduction in time spent with target level blood glucose readings, meaning that there must have been an increase in levels over target. The consequence of this was an increase in the HbA1C levels of participants using the AP. From a safety and day to day lifestyle point of view, this is a hugely positive result however, the worry is that the long term outlook may be less positive with an elevated HbA1c level due to more blood glucose reading levels being over the target range.
There is a definite, two fold benefit to the elimination of night time hypoglycaemia. The first of these benefits is that of safety. The worry of falling in to an un detected hypo during the night which could then lead to a diabetic coma is significantly reduced. The second is quality of life, if the individual is not having to test and treat hypos in the night, they are likely to be getting more undisturbed sleep which will have a direct impact on their energy levels and general wellbeing throughout the day. These benefits, however, are potentially outweighed by the increased HbA1c and the risk of complications which come along with this.
An increased HbA1c level in the case of decreased hypoglycaemia and more time spent in target would be a positive result however, in this case the reduction in hypoglycaemia has come at the cost of decreased time in target. The only conclusion that can be drawn from this is that the patients spent increased time with blood glucose levels higher than target which is a contributory factor to concern regarding long term health.
The basal insulin requirements on the AP were, on average, less than those on the SAP however, the total amount of insulin required (basal and bolus combines) was almost exactly the same on both systems. This shows the benefit of the closed loop system in that it’s calculations of basal rates are based upon a CGM reading and can be adjusted on a constant basis. Although all participants of the study, whether on AP or SAP, were connected to a CGM device throughout, the closed loop element of the AP meant that it could calculate the basal rates and adjust them at a much faster rate than with the open loop system where an element of human decision and action is required. The AP, closed loop system, therefore, was more effective at reducing the peaks and troughs experienced on the SAP, open loop system and, assuming that the individual was able to carb count and match their bolus insulin dose accordingly, this resulted in a more steady and stable period of blood sugar readings.
In conclusion, the AP system is very effective at managing the basal insulin provision and has the huge benefit of reducing levels of hypoglycaemia which can be scary and temporarily debilitating for the sufferer. The cost of this was an increase in levels higher than the target range and consequently a higher HbA1C result. I feel that as an initial product, there is huge promise and potential for the AP system and with some tweaks here and there, it could definitely become a more reliable method of gaining improved blood sugar control.
Wow – I feel like I am back at uni, reading and analysing research papers lol. Sorry – bit of a dull read and I didn’t mean to go on for so long…
Next time I’ll tell you about something REALLY FUN to make up for the seriousness!