### mg/dl and mmol/l

Americans use mg/dl as the unit for measuring glucose levels. Most other countries use mmol/l. The relationship between the two is that 1mmol/l = 18mg/dl. I was interested to understand this relationship (as a former chemist) and also find out what it meant in practical terms. It is a bit sad, but here is my calculation (previously posted on diabetesdaily.com in response to a question):

The unit mmol/l stands for milli-moles per litre. (or liter in the US, I believe). milli means a thousandth, so what is a mole (other than a small rodent-like animal). A mole is that quantity of a substance whose mass in grams is the same as its formula weight (atomic weight). Each molecule of glucose has 6 Carbon atoms, 12 Hydrogen atoms and 6 Oxygen atoms. A carbon atom weighs 12 units, a hydrogen atom weighs 1 unit and an oxygen atom weighs 16 units. These units are called relative atomic mass units (don't need to go into why). So the atomic weight of glucose is (6x12) + (12x1) + (6x16) = 180. Therefore one mole of glucose weighs 180g. So now we are in a position to look at mmol/l. 1 mmol of glucose is 0.18g. So 1 mmol/l is 0.18g in 1 litre of water.So now you can see the relationship to mg/dl. A decilitre is a tenth of a litre or 100ml. A miligram is a 1000th of a gram. Therefore 0.18g is the same as 180mg. We are only dealing with a 10th of the amount of water (100ml or 1dl) so therefore can divide this number by 10 giving 18mg/dl. Thus 1 mol/l = 18 mg/dl.

Finally, for those who are interested in how sensitive our glucose meters are, think about this. Mine does graduations in 0.1 mmol/l increments. As shown about 0.1mmol is 0.018g. I think it is remarkable that I have a handheld, portable device that can tell me differences of 0.018g of a substance in a litre of liquid! Probably bored you silly, but I didn't know why this relationship existed until I sat down and calculated it, so at least I have learnt something!

One more thing has struck me. How many grains of sugar is 0.018g? After some research, I think I may have found the answer. According to a site I have found, the density of granulated sugar is 849kg/meter cubed. Another site says that granulated sugar granules are cubes of side 0.5mm. Knowing the density and the volume of them you can work out the mass. Mass = Volume x Density. Not to bore you with the maths...1 grain of sugar weighs 0.106mg (as long as I have got my conversions right). Therefore 0.018g of sugar equates to about 170 grains.

Phew! Going for a lie down now!

### Big Announcement - Libre Funding

NEWS RELEASE Embargoed 00:01 November 14 NHS TO PROVIDE LIFE CHANGING GLUCOSE MONITORS FOR TYPE 1 DIABETES PATIENTS Tens of thousands of people with Type 1 diabetes across the country will benefit from life changing glucose monitors on the NHS. To coincide with World Diabetes Day, Simon Stevens, Chief Executive of NHS England, is announcing action to end the current variation patients in some parts of the country are facing to access Freestyle Libre. The wearable sensor does away with the need for inconvenient and sometimes painful finger prick blood tests by relaying glucose levels to a smart phone or e-reader. NHS England will ensure the device, which is the size of a £2 coin and sits on the arm, is available on prescription for all patients who qualify for it in line with NHS clinical guidelines. From April 2019, these patients will be able to receive it on prescription from their local GP or diabetes team helping them to better manage their blood sugar levels. It comes as the NHS seeks t…

### Libre - March 2018 Update

Since November 2017 and the official listing of Libre on prescription, so much has changed, but has it changed for the better?

I think broadly the answer to that question is No, but not for want of trying.  The situation has become increasingly confusing and disjointed.

Getting it on Prescription Firstly, the prescribing of Libre.  Wales have said yes, most other areas have said perhaps.  This map shows the current status by CCG: Diabetes UK Joint Policy Tracker.  There are improvements, but this demonstrates the postcode lottery.

The data on prescribing rates are published but this data is woefully slow to become in the public domain.  The final UK country to publish data was Scotland, which finally released December data on 13th March!

Here's the data so far:

This shows an increase, but hardly an avalanche!  Wish I could see the January data...Northern Ireland should publish very soon though.

There are CCGs like Manchester that have now approved prescribing, but it's slow an…

### August Libre Update - Data, data and more data!

This month's update will be dealt with in two parts, both focusing on data; the first part summarising some data about the prescribing policies across England, the second my usual update on prescriptions fulfilled across the UK.
Libre Prescribing Policies and Implementation in England There didn't seem to be an easy way to compile this.  I used the Diabetes UK Map to link to the policies and then I cross-checked this with a Google search to see whether there was any more information.  I had to do this line by line for each of the 195 CCGs in England - quite a lengthy and tedious process.  However, I am pleased with the information arising from the data.

Firstly, the headline figures - how many CCGs were funding Libre, how many had denied funding and who were still undecided?  There are differences of opinion about these figures as some CCGs have not been clear (Staffordshire CCGs), and some have agreed to fund, but are yet to actually fund due to implementation difficulties (L…