Matters arising

April 2017

After the parking episode described recently, I think I have not written about my other parking issue, because parking is one of the least interesting and most discussed issues of modern times. Outside my garage there is a white line to indicate that parking is not permitted across the entrance. As we have seen when it was removed by the re-surfacing works this line served a useful purpose, but it was only just long enough, and cars parked legally would slightly obstruct the garage entrance, but not enough to stop me getting in and out. I wrote about this briefly in a previous post, and eventually did contact the council's white line department to ask if it could be lengthened, to which they said 'No'. However, after the re-surfacing work the line was re-painted at the longer length that I had been asking for. So that's interesting. Or, more accurately, it isn't. Enough with the parking already.

I went to a local meeting. Some money has been allocated to be spent on improvements to the park at the end of my road, and the council thought they'd ask the locals what they would like. There was already a prototype group to ask, because the Friends of the Park had been convened when the park was threatened with being taken over by cars, caravans and motor homes during the National Bowling championships in the summer. It was a good meeting, and surprisingly good humoured and constructive. The main problem seemed to be the newly installed skate park, which is very popular and attracting swarms of local 'yoof', but is also attracting their litter despite the many litter bins in the vicinity.

The yoof in attendance were polite and well-spoken and made good points. There were also representatives from the bowling club, the tennis club, local dog-walkers, parents and runners who are the main constituency of park users, as well as all the candidates for the local election taking place a couple of days later. It looks as though the most likely purchases may be outdoor gym equipment (but there is a separate pot of money that may fund this anyway) or a refurbishment of the under-used tennis/cricket pavilion to make it more usable for e.g. a cafe. My previous local councillor who I can no longer vote for was there, and I took the opportunity to thank him and express my regret that he would no longer be representing me.

Work news: I delivered the 'short carb counting course' pilot. Prizes are available for anyone who can come up with a better name - my best shot at the moment is Candi, which stands for Carbs and Insulin. This comprised four hours about carb counting extracted from our usual four days about Type 1 Diabetes, to deliver to people who can't spare four days and maybe don't have Type 1 Diabetes. We had five attendees and I think it went well. I have yet to look at the feedback sheets.

We also had a small meeting attended by our business manager, two doctors, three nurses and me. It was supposed to discuss the future of the insulin pump service, which is set to expand by about 10% every year. As usual the meeting was utterly pointless and did not result in any useful discussion or conclusions, but it was quite a nice social event within the department. We are having a follow-up meeting with just three of us, which may be more constructive. All I actually want from the meetings is to understand how our service is funded and managed. It doesn't seem much to ask, but so far I have failed to achieve even this small advance.

Two CPD courses for me last week as well - the first about Clinical Audit presented by one enthusiastic and knowledgeable man and one girl whose presentation style was simply to read out loud the text written on each Powerpoint slide. I tried to be constructive in my feedback, but she was terrible. I discovered quite a lot about Clinical Audit, including the fact that what I planned for evaluation of the short carb counting course isn't Clinical Audit at all, it's Service Evaluation. The other course was a compulsory three-year update on DESMOND, the Type 2 patient education product. Also very interesting, and delivered in the same rooms of the same hotel as the first big Techshare conference that I helped to launch and run in the 1990's.

Much leisure activity to report - the music group continues, with the prospect of me being the sole baritone saxophonist at the July concert because my fellow saxophonist has a previous engagement. There are significant exposed baritone solos in the pieces we are playing, and I am not at all confident of successful delivery, seeing as how I'm really not very good at playing the beast even though it is enormous fun.

I also spent a whole day with the Buddhists at our usual venue - a nearby village hall - and the weather was lovely and we did some meditation, some chanting, some discussion and another 'puja' ritual. I still don't think I'll be joining in with the rituals any time soon, but for the first time I really felt that I had made progress with the meditation. It's been so gradual that it's hard to detect, but it feels easier to do and in my everyday life I am employing some of the positive behaviours that it's supposed to promote, and and feeling better for it.

The LTRP took a step forward with the rebuild of the airing cupboard, which looks lovely and needs only to be painted. While they were here the carpenter and his mate were kind enough to carry my filing cabinet upstairs to the new office, about which I am disproportionately excited. I also went back for a second meeting with the woman from the alternative kitchen supplier who has very strong views on her products and doesn't mind sharing them, and who speaks very loudly. I am trying not to be too influenced by these factors and to focus on the content rather than the style of delivery.

Shopping, touring and parking

Borough Market, May 2016

Sometimes I don't have much to say, but at the moment I'm almost driven to the keyboard to let off a bit of steam. Actually, the pressure has dissipated a bit because I've told most of the hairiest stuff to Lola II and Mr M on the phone already, but writing it down can help too.

While you've been enjoying the niceties of diabetes technologies, activities at Lola Towers continue unabated. I think I am actually unable to lessen the quantity of stuff going on because I'd rather have too much than too little to do. Accepting that this is true may help me to stop moaning about how busy I am.

I have had a bit of a shopping spree - online, of course. With some actual camping coming up, and also with the prospect of being without a kitchen for a while over the summer, I decided to get a move on and decide on what sort of camping stove to get, followed by actually buying it. So that's one thing crossed off the enormous 'To Do' list.

The building where I work is fairly relaxed but the hospital as a whole is trying very hard to make sure that quality standards of all sorts are maintained, and the latest standard to be addressed has been the one about uniform: bare below the elbow and hair above the collar. The Dietetic Manager sent an email round to highlight this, and I have had to accept that if I am caught transgressing now it will be rather more of an issue than before we were specifically told to abide by the rules.

Keeping hair tied back is fairly easy and I can manage fine without a wristwatch, but I do find that the wristband Fitbit pedometer has helped me to carry out a bit more activity and a few more steps every day, and I was reluctant to give that up. So I also rode the wave of rare shopping motivation to try and use up all the remaining TV-watching points on a Fitbit device that clips to clothing so I wouldn't have to wear it on my wrist. Unfortunately after I'd ordered the TV-watching vouchers it turned out I couldn't use them to buy this gadget, but I bought it anyway with real money. Within a week I had gone and put it in the washing machine. [It has a surprisingly effective rubbery jacket, so it survived unscathed!]

Local elections came and went - constituency boundary changes meant I had to choose a new candidate to vote for, and I am glad that the incumbent Green Party candidate was elected - small patches of Green and Lib Dem yellow appear among the sea of blue in this county. I am dreading the General Election. Each time there are more hateful personalities and policies among the distorted propaganda, political bickering and biased media, and less integrity, honesty, generosity and truthfulness. It has become a choice between wasting a protest vote, or tactical voting for the least detestable party that stands a chance of ousting the most detestable. Sometimes democracy is a burden.

Lola II and I went to Shrewsbury for her 'birthday' weekend this year. It is rather a nice city, with river, hills, interesting independent shops and many many coffee shops and churches. I bought a rug! It was a bit of a surprise but maybe this shopping thing I seem to have acquired is seasonal. There was a rug shop in the market, and we had a bit of a think about how to manage a rug purchase when we were spending the day wandering about and staying in a B&B, but the vendor agreed to deliver it to the B&B. The rug is red and black and very striking. I like it.

Other things we did in Shrewsbury - a rather interesting guided walk looking at buildings all round town from medieval to modern times. Particularly interesting was the half-timbered building faced with brick to fit in with the style of the newer Regency buildings around it. We were also shown a modern frieze on a building, including a small plaque containing two faces, and asked who they were. Lola II guessed one as the Queen, and rather flippantly I said the other looked like Michael Heseltine. My guess turned out to be right, and the other face was Margaret Thatcher - the frieze was a reference to the introduction of the Poll Tax. We ended Saturday with a local theatre company performing 'Anything Goes' which was a delight.

On Sunday Lola II and I did a lot of walking and talking and had a Japanese lunch, which made me happy. And during the weekend my ebay sales record was broken by a postcode promotion leaflet much like all the others, except that it featured Sherlock Holmes on the front. It was clearly Sherlock fans rather than the more sober philatelic collectors who bumped the successful bid up to a frankly ridiculous £16. I was even more delighted because I happened to have two of the same leaflet, but the person whose offer of £15 was outbid must have come to his or her senses, because they failed to take up my Second Chance offer at that price.

The only other recent event of note was on a Friday when, most unusually, all my clinic slots were full and I was expecting seven people in the morning. Out of the front door as usual in the morning I was confronted with a car parked right in front of the garage, completely preventing me from getting the car out.

The road was resurfaced a few days ago so all the road markings were missing, and this might have contributed to the situation. No matter why, the question was, what do I do? A few neighbours were out and about but none knew whose car it was, so I phoned the police non-emergency number for advice. A friendly woman took the details and asked if I had knocked on any neighbours' doors. I caught the hint and asked if it would be worth my while - could she perhaps give me the address that the car was registered to? No, she couldn't tell me the address, but yes, it would be worth my while to try a few doors. Meanwhile, she would pass my case to 'Despatching' who would send someone over when they had the chance.

I really didn't fancy knocking on doors at 8 o'clock in the morning, so I waited. At work, my colleagues had started to contact the patients who were booked in - unfortunately a couple turned up anyway because they hadn't checked their phones. An hour later I phoned the police again to see if I should just cancel the whole morning's clinic, and got the distinct impression that nothing was going to happen very quickly. Another hour later I did get a phone call, and this time the policeman told me which house the car owner lived in, but there was nobody at home, so I put a note through the door. At this point I tried contacting the council parking enforcement department, who also said they would send someone round although we agreed that there was very little that could be done.

After a further hour (now it was after 11 o'clock) the police controller called me back to see if anything had changed. I didn't see how any policeman could help me unless they could track down a mobile number for one of the occupants of the house, and it didn't seem like that was something they were going to do. She said she'd send someone round anyway because they might be able to move the car, which would have been really interesting to watch.

At 12.15 p.m. there was a ring at the door - the neighbour had returned from a very unimportant trip into town and was distraught at the trouble she'd caused. She hadn't noticed the garage, she was busy telling the kids off when she'd parked - it was hard to be angry at a genuine mistake and she acknowledged how it had really messed up my day. We did agree that it was unlikely that she'd do it again.

Bolus advisor masterclass part 2: Post-prandial correction

Cotswold Falconry Centre, April 2017

The first instalment of feedback from the recent course I attended was mostly about adjusting insulin dosage to account for fat and protein content of meals. The second half of the course left several delegates behind...

Post-prandial correction doses

This was by far the nerdiest section of the course, and took quite a bit of concentration and asking the presenters to 'just say that again more slowly.' It was all about how the bolus advisor technology built into blood glucose meters and insulin pump handsets works out correction doses of insulin when blood glucose is high following a meal.

Unless you have a fully functional pancreas, you cannot avoid your blood glucose rising after a meal, even if you have injected the 'right' amount of rapid-acting insulin. Trials have shown that for the rapid insulins currently on the market, the ideal time to inject is 15-20 minutes before a meal. This is usually impractical, because you don't know how much insulin you will need until the food is in front of you, and then you don't want to wait 15-20 minutes before eating it. So the period when the injected insulin is reaching the peak of its action ('offset time') lags behind peak glucose entering the bloodstream, and this is one reason why post-prandial blood glucose tends to rise more than for a person without diabetes ('meal rise'). But if you've worked out the right amount of insulin, your blood glucose should return to 'normal' levels within four hours, which is the 'acting time' for rapid insulin.

So if you monitor your blood glucose less than four hours after your last bolus or injection, the blood glucose level that you see may actually decrease further without any action from you, due to 'insulin on board' - active insulin still in your system. So how do you know whether to correct it or not? At any time within four hours of your last injection, how high is 'too high'?

Imagine a scenario where your blood glucose level is within the ideal range before a meal, you have counted 60g carb in your meal and your insulin to carb ratio is 1 unit for every 10g - this means you will need 6 units of insulin. Roche told us that other manufacturers' algorithms assume that all insulin injected is 'active' insulin. So if your correction ratio is 1 unit of insulin to reduce your blood glucose by 3 mmol/L, then immediately after the meal your blood glucose could be up to 18 mmol/L higher than its pre-meal level and you would not be advised to take a correction dose because of the 6 units of active insulin. Roche also told us that other manufacturers assume a linear reduction in blood glucose, so after 2 hours your blood glucose could still be up to 9 mmol/L higher than the pre-meal level and no correction would be advised.

Fig 1. Correction is not advised if blood glucose falls below the line

This is not good. Even in the worst case scenario, blood glucose should not rise this high after a meal. There's no perfect number to aim for, but (assuming the meal wasn't Frosties) I would be happier with a meal rise of no more than 4 mmol/L, and 3 mmol/L would be even better.

Roche's algorithm makes quite a different set of assumptions, the main one being that only pre-prandial correction doses (insulin injected because pre-prandial blood glucose is too high) count as active insulin after the meal. Insulin injected for carbs is accounted for, and is not available to act on a high post-prandial blood glucose level. They say they have evidence to support this assertion.

So for Roche, a correction is required if the blood glucose rises higher than the 'meal rise' setting during the 'offset time'. After that a linear decrease to the pre-prandial level by the end of the 'acting time' is assumed. If meal rise is set to 4 mmol/L, offset time is 1 hour and acting time is 4 hours, then a blood glucose rise of 9 mmol/L at 2 hours would definitely suggest a correction. The shorter the offset time and the smaller the meal rise settings in the handset, the more aggressive the correction regime. For someone frail and elderly or prone to hypos it makes sense to have a higher meal rise and a longer offset time, to minimise risk of over-correction and hypoglycaemia.

Fig 2. Correction is indicated for the same post-prandial blood glucose level as Fig 1

Blood glucose correction after snacks

This was the hardest part of the course to understand, and therefore to explain. It would be so much simpler if people with Type 1 diabetes didn't eat between meals! But given that they do, they need advice on whether to correct blood glucose after a snack. The aim of the 'snack size' setting is to determine whether to apply a 'meal rise' and 'offset time' or not.

The 'meal rise' setting doesn't change depending on the size of the meal; it is the same whether the meal is small or large. So the 'snack size' setting is the carb threshold between applying a meal rise or not. If 'snack size' is set to 20g of carb, then for snacks up to this amount correction will be indicated afterwards if blood glucose is above the line in the previous graph. If a 'snack' 2 hours after a meal contains 30g of carb then the meal rise is applied at that point and a new graph is drawn, with corrections only advised for blood glucose levels above the new line.

Fig 3. Presence of the meal rise allows post-prandial blood glucose to be higher without advising correction

This is pretty sophisticated stuff, and I'm pretty sure that none of our patients understand how these settings are used. I'm only just working it out as I write this. What it boils down to is that most people using a basic type of meter have to take a stab in the dark when correcting post-prandial blood glucose levels, but people who are using this technology should get a good indication of whether to correct and how much insulin to give, as long as the settings have been adjusted to meet their particular requirements.

I always try hard to make sure that the main insulin to carb ratio and correction factors are right, but I have been less attentive in the past about the meal rise and snack size, because up to now I didn't understand what they were for.

The last point to mention is what we can do for people using pumps and meters that use the linear algorithm in Figure 1, which don't give useful advice about post-prandial correction. The team delivering the training suggested shortening the acting time setting to 3 hours instead of 4, because then at least a few more high blood glucose levels will fall above the line. This is not ideal, but the best they could come up with.

Bolus advisor masterclass part 1: Counting fat and protein

Seville, November 2016

It's been a few weeks since I attended this course, and it's time to assemble my thoughts and learning points. It was a terrific day and I certainly learned quite a lot, most of it very relevant to my work with people with Type 1 diabetes. In fact, two days after the course I was passing on some of the information to the group I was teaching at the time.

It is important to note that the day was hosted by one particular pump manufacturer, Roche, so there is a likelihood of bias. Having said that, I think the majority of information supplied was correct - it would be fairly straightforward to check, although I haven't done so. The first topic covered in the day was a comparison between the specifications and capabilities of the different insulin pumps on the market. Then we focussed on the algorithm that each manufacturer uses to guide the user in the amount of insulin to give in various circumstances: for exercise, for high fat and protein meals, and to correct high blood glucose levels after a meal or snack.

Exercise

The guidance around exercise wasn't very different from what we already advise - if you're exercising within 90-120 minutes after a meal you could give less insulin for the meal; if not then you'll probably have to eat or drink some carbohydrate to prevent blood glucose dropping, and if you're using an insulin pump you've also got the option of reducing background (basal) insulin. I've written extensively and comprehensively on the knotty topic of exercise and Type 1 diabetes. It's a challenging area, and management.is very individual. All the pumps work in a similar way, although the Roche handset has some features that help with the mathematics of percentage reductions.

High fat and protein meals

OK, this is going to start getting technical (although nowhere near as nerdy as the section on post-prandial correction doses in part 2).

For people with Type 1 diabetes, the evidence suggests that best management of blood glucose levels, and therefore long-term health and freedom from diabetes-related complications, comes from matching insulin injected and carbohydrates consumed. (Just for contrast, the approach for people with Type 2 diabetes in the first instance is weight loss).

The first point that hit home during the course was that although we focus on counting the carbohydrate in a meal, there is a contribution to blood glucose that comes from the protein and the fat in a meal. When we focus on carb counting, there is an unspoken (and for me until now, unrecognised) assumption that the meal is constituted of a 'normal' proportion of carbs, fat and protein. I actually know this to be true, because we have found when someone with Type 1 goes on a very low carb diet they need more rapid insulin with meals than the carbohydrate content would suggest.

Fat and protein have another effect alongside their contribution to blood glucose levels - they also slow down the digestion of carbohydrates. The action profile of insulin can't be adjusted to suit the meal composition - rapid insulin has a fixed onset, peak and acting time that doesn't change, so giving insulin in the standard way before a meal when it's a high fat/protein meal doesn't work very well, and post-prandial blood glucose often ends up way higher than one would like.

Up to now, conventional wisdom suggested that for a high fat meal carbs should be counted as usual, but the matching insulin dose should be delayed and/or split (if on injections) or spread over a longer time period (if on a pump), to account for the delay in digestion and later peak in post-prandial blood glucose. This course not only suggested that more insulin is needed because of the greater contribution of fat and protein to blood glucose, but gave some useful guidelines on how much more is needed, and how it should be delivered.

Six different high fat/protein meals were listed: fish and chips, Indian and Chinese takeaway, pizza, pasta with creamy sauce and fast food (McDonalds, KFC etc).  The following procedure was recommended separately for each.

As a first attempt, you should give 25% more insulin than you need for the carbs and deliver 50% at the start of the meal, and 50% an hour later (if on injections) or over 2.5 hours (if on a pump). Then, to see if these percentages are right, you should monitor blood glucose at 2.5 hours and 6 hours without having any more food or insulin. This will work best if your blood glucose level is within the normal range before the meal.

The 2.5 hour test is to find out whether the 50/50 percentage split is right. If blood glucose at this stage is more than 4 mmol/L higher than it was before the meal, then more insulin is needed up front - they suggest increasing by 20% at a time (i.e. switching to a 70/30 split next time). Conversely, if blood glucose is lower at this point than before the meal, the split should be changed to 30/70.

The 6 hour test is to find out whether the 25% extra insulin is right. If blood glucose at this stage is between 2 and 6 mmol/L higher than before the meal, next time add on another 10% - instead of 25% extra, add 35%. If at 6 hours blood glucose is more than 6 mmol/L higher than before the meal, next time add on 20% (to 45% extra). Conversely, if blood glucose is lower at this point, then next time knock the percentage down by 10% to 15% extra.

Multiple experiments may be needed to get the best results! Apparently parents are often taken aback when their Type 1 children come home from a carb counting course and assert that they've been given homework that requires them to eat fish and chips, takeaways and fast food.

Coming soon: Part 2 will contain even more technical stuff about how to manage post-prandial correction of high blood glucose levels.