Friday, April 29, 2011

It's been a heckuva day. I woke up this morning to a Dexcom reading of 46. So I ate about 12g of taffies in bed, tried to convince myself to get up. Half an hour later, I'm still in bed, Dexcom says LOW. I test on my meter, it says 42. Okay, that's not exactly "Under 40" but it's within 10%. I eat some more taffy, head to the fridge and finish up the almond milk (low carb but high glycemic index- usually shoots my blood sugar right up).

I head over to my parents' for breakfast, eat about a quarter of a large pineapple, a roll, and some mints. I take three units of Novolog. My blood sugar is trending upwards when I leave the house for work. My breakfast spike, such as it was, is over by the time I get to work, at 88 with a down arrow. I eat taffies all morning. At lunchtime, Dexcom says 48 and the meter says 66. I eat all 40 grams of carbohydrate lunch (a muffin and a cucumber) and don't take any insulin. Dexcom shows my blood sugar hitting 90 as I leave work. My meter says 110. I go hypo on the way home. Two more taffies (each 6 grams of carbohydrate) fail to get my blood sugar over 100. Once home, I eat more taffies. No dice.

So I was particularly gratified to find a message on my machine from a nurse practitioner working in the nuclear medicine department of Northwestern. She wanted to go over protocol and specifics for my gastric emptying study, which is scheduled for Monday morning. I called and left her a message and even though it was after hours, she got back to me within a few minutes.
She said that actually, I could eat until 4 AM the morning of the test, not just to midnight. She said that their new protocol, which they are transitioning to now, says that they want blood sugar under 200 at the time of the test (this is a very good thing IMHO- the test is not really meaningful at high blood sugar because many people have delayed gastric emptying with hyperglycemia but not with euglycemia), and that if the blood sugar is slightly higher they might go ahead anyway. She went over the food issues, said to bring my meter and insulins (as if I would come without them!) and was responsive to my comments.

The gastric emptying test in diabetes is actually a pretty perfect example of why logic matters in medicine. But I have to get off the computer now, so I'll type up the question tomorrow.

Thursday, April 28, 2011

Consider Data Collection Biases

I am thinking about writing a series of posts in which each post illustrates how I look critically at scientific/medical data.

For instance, for each of the years 1999-2007 inclusive, the CDC has published a long document that says how many death certificates issued in that year were for people of each year of age, as well as what race and sex were put down for those people. Here is the link:

Now, there is lots of data to be found in those tables. One thing that struck me was that 68 people are listed as having died at ages 115 or older in that 9 year period. OK, so far so good. Out of those 68, only 18 had their race listed as white. Only 11 out of the 68 had a recorded sex of male, with three recorded as white male.

Since roughly 85% of all deaths were in white people, and roughly 50% of all deaths were in male people, this means that if recorded age at death didn't have to do with sex or race, you'd expect that 57 or 58, rather than 18, of the people who died at age 115 or higher would be white. You'd also expect that about 34, rather than 11, would be male. So in fact, being white or male cut down the odds of making it to age 115 on the death certificate by two thirds.
Looking only at rates of people who've made it to 100, the picture warps further. In people whose death is recorded at age 100 or greater, men make up about 1 in 6, so that there being 11/68 of them 115 or older is not at all surprising. White people, however, make up about 10/11 of people with death recorded at 100 or greater, making their absence in the group of people 115 or greater even stranger.

Okay, good, now let's step back from the data for a moment. If you were a newspaper journalist and you wanted to report on the statistics above, you could choose a lot of different slants.
You could claim, "African Americans Weather Last Years Better, says CDC."
You could claim, "Whites Unlikely to Be Longest Lived."
You could claim, "Minorities Reach Majority at age 112."

Or you could be a little less certain. The death rates as I see them do prove something. They prove that in the United States during the period 1999-2007, White persons were less likely to have an age greater than 112 written on their death certificates. We could be reasonably certain that this also translates to a similar expectation for 2008, 2009, and 2010, since the trend was not really changing, and the margin was very muchly significant.

What we couldn't know, however, is whether those records represent the actual ages at which people died. Maybe, for some reason, a gene that makes death less likely in the eleventh and twelfth decade of life is more common in non-white populations, or non-whites do a better job with elder care, or something. Maybe the CDC statistics do represent that. I like to think that's so, just because it's kind of a cool possibility.
But the other possibility is that age is reported differently based on race (or based on something that is statistically different in different racial groups). Maybe, a hundred years ago, white people were more likely to have accurate birth certificates. Maybe for cultural or other reasons, non-white persons are more likely to have their ages misrepresented on their death certificates. Maybe, particularly since these people were born in the era before social security numbers, Black people were more likely to claim to be older than they were when applying for such things. Maybe doctors are sloppier when writing up death certificates for non-white persons.

Which leads to another tenet of mine: if data can support more than one conclusion... look for more data!
In this case, I don't have access to the other data that would help, but the kind of data I'd like to see are survival rates to age 115 or older in a variety of other countries. Do countries with better or worse record keeping have similar or different results? Will this trend in death tables continue past the years where all people dying were likely to have gotten social security numbers at birth? If we look at the people with no age written on American death certificates, will we find a racial bias? Will it be enough bias to explain our data away?
What will CDC data show in twenty or thirty years, when we can expect that the data collection at the births of our oldest citizens will have been much improved?

Not at all D-related: I have a kindergarten chess class on Wednesdays and yesterday in class, one of the students came up and tattled, "Nico said the B-word."
So I look, kind of dubiously, at Nico, who is looking teary eyed. And the kid insists, "He did! He said, 'Sit on your...'" and the kid leaned in and whispered, "butt".
It was all I could do not to laugh.

Tuesday, April 26, 2011

Evaluating Medical Claims

Today I was talking to an almost-doctor (graduates med school in two weeks) I know in a social/religious context. We were talking about various things and he said he'd like to see more of me and I said if he wanted to set up a schedule to do some studying, I'd be open to that- what would he like to study? I was intending for him to name a religious topic.
But he said he'd like it if we could be medical chevrusas*, maybe, if he has time for regular get togethers, which he isn't sure he does. If we could pick a medical topic and then both of us read up on it, and get together to discuss it.

And then I started thinking about ground rules for discussion of medical topics (I also started thinking about medical topics that might be interesting to discuss- the major ones that come to mind are issues of debate such as chronic pain management). That struck me as being relevant to a comment I got many posts back when I wrote about the credibility of the big pharma and the medical establishment. I was asked what I thought of alternative medicine. So here are my thoughts.

1. Speculation is interesting but takes a back seat to evidence.

2. The only evidence that counts is data, not theories, not what a doctor says, and not a textbook recommendation. If somebody doesn't tell you how he knows something, he doesn't know it. Evidence that I consider relevant is practically everything: animal and human studies, case studies, molecular studies, studies on the disease in question and on related diseases, and epidemiological data. Especially epidemiological data.

3. Evidence never proves anything other than that it exists. It suggests many things. When considering evidence, look for the data source, not the researchers' interpretation of it, and always keep the limitations in mind. For instance, the time and place, type of research subjects if any, lab norms if any, data not given, placebo effect, and other variables.

4. The placebo affect should always always always be considered in human studies, particularly case studies. This is why you will get testimonials that something works when it doesn't. People think they got better because of the pills when actually it was their belief in the pills.

5. The related phenomenon is false attribution, for instance, if a doctor (or patient) claims the patient got better because of the medication, whereas the patient got better just because he happened to get better.

6. Understand the values or motivations of researchers when evaluating their advice.

Medical studies or advice is often based on a value system, sometimes more obvious than other times. A recommendation to take a medication may stem from the belief on the part of the doctor or researcher that the disease is worse than the side effects of the medication. Identifying these values is important because many researchers and some doctors are not even aware that there are other value options.
For instance, your doctor may believe that it is better to take fewer shots even if this raises your A1c a bit, because he thinks that taking shots lowers your quality of life. You may or may not agree.
In a less obvious scenario, a study came out a few months ago claiming that obesity lowered life expectancy even more than previous studies said. Upon closer inspection, this was because the doctors were looking at quality of life years- and they had decided that quality of life with certain obesity related diseases was even
worse than other researchers thought. The issue was not life expectancy- it was researchers' opinions about how much fat people could enjoy life.

7. Understand the definitions of the people or diagnoses being studied.
I'm sure all of my readers can understand what happens when rule 7 is not followed- you get people talking to you about a diabetes that isn't the one you or your kid has.
When you know who was included in a study, you have a better idea of who it is relevant to, and what it means.

8. Understand sample bias. When looking at any study, it helps to understand how certain people came to be participating in the study. People included in a study on "natural medicine" are likely to be people who like the idea of natural medicine.

9. Sometimes people lie.
Mostly in looking at medical research, this is (hopefully) an accident where the conclusion doesn't really match the data. Sometimes however, doctors and scientists have been known to falsify data. In case studies, there is often a possibility that things didn't go exactly the way the patient or parent says they did. And when doctors or other people administer surveys with multiple choice questions or even open ended questions, there is a HUGE potential for misunderstanding.

10. Nobody is average about everything.
If a study shows that a medications lasts for 26 days in the average subject, that doesn't mean that it can't last 96 days in you. Or 2 days, for that matter.

11. Nothing affects just one thing.

12. If A and B happen in a given relationship every time, your researcher will often assume A causes B. The logical possibilities however are:
A causes B
B causes A
C causes A and B
the researcher didn't really test enough to be sure about every time and it was chance

*Chevrusa is a Hebrew word that refers to a study partner- typically a study partner with whom one studies a religious topic.

Sunday, April 24, 2011

On Thursday morning, sensor 19 having been in for a full three weeks and starting to act up (???s and false lows), I pulled it, took a bath, and put in sensor 20. One thing I hate about changing sensors- I change sensors in no small part because the old sensor is not working really well and I want fewer ??? episodes and better accuracy. So I put on a new sensor, and for the next two days I might get better numbers, but more often than not, I get less accurate numbers and sometimes ???s. At first I tend to wonder if the sensor is a bust or if I misremembered how accurate the previous sensor was.
This sensor took a few days to shape up in terms of accuracy and is now doing pretty well, although overacting a bit to lows and highs (it claimed I was LOW when I woke up this morning, whereas my meter said 46).

As you know, my insurance policy changed to cover CGMS usage in people in my demographic (under 25s with type 1 diabetes, intense blood sugar control efforts, and labile blood sugars) on Jan 1, 2011. I called Dexcom to ask them to get me coverage in light of this new policy and they confirmed that I ought to be covered on Jan 18th. Dexcom then sat on its ass. On March 23, my doctor and I filled out all of the forms that Dexcom could want and the doctor faxed them over while I waited in his office. No word from Dexcom.
Last week I called to bug the rep who said she would get me coverage. I left her an irate message, and an hour or so later got a call from the person who apparently replace her. The new person didn't know anything other than that she'd just been forwarded some of the paperwork from my doctor, on which a diagnosis code was missing, so she called to talk about what we could do if I had a miscellaneous form of diabetes (I don't). I filled her in, she said she thought she could get me coverage within a week but would update me within a week in any case.
It's been a week, and I did get an update. Apparently my insurance might cover without pre-authorization, she wanted to know if I wanted to place an order now or get pre-authorization first. Of course I want pre-authorization, I already HAVE sensors!!! So hopefully next week I'll have authorization aka coverage.

I'm thinking about placing the next sensor on my butt. I was trying to figure out where on my butt a sensor would go. I'm thinking maybe to the side? Where do people place sensors and infusion sets when they wear them on their butts?

Oh! And I drank about three cups of low alcohol (about 3%) Rashi wine on the first night of passover. I then took a little less insulin for the meal as well as for the overnight. I went high after the meal, came down really smoothly and had a great blood sugar night.
The second night I didn't drink any wine (different household, different wines available) and had a similar meal time blood sugar experience. That night I forgot the Lantus (!!!) so I really can't compare it to the previous night. On the plus side, I didn't get ketotic.

I've been thinking a lot lately about life expectancies in various contexts and what people expect from life when childhood mortality is low. About how most Americans assume that their kids will grow up, that it is an outrage that one kid might die... but in many countries, kids die as a matter of course. Malnutrition is among the leading causes of childhood death in South Africa, a country in which life expectancy is in the 50s, and a quarter of deaths in 2000 were related to HIV. More than a dozen countries have a mortality rate for children under of five years of 1 in 6 or higher.

Sunday, April 17, 2011

On Being a Medical Geek

I have Asperger Syndrome. One of the hallmark features of Asperger Syndrome is interests that are unusual in intensity or focus. Personally, I'm something of a polymath- I like to learn about everything. I have never been interested in one thing to the exclusion of all other things. But it is clear to anybody who has ever engaged me on certain topics that there are some topics that just get me going. And going and going and going.

I have always been fascinated by disability. Before I was diagnosed with diabetes, I focused more on the ways that disabled people function in society, self-perception, etc. I had already just so happened to have read two nonfiction autobiographies by type 1 diabetes (unfortunately this left me with the misconception that diabetics couldn't have any sugar). After I was diagnosed with diabetes, my fascination with disability very slowly morphed into a more medical fascination.

Being fascinated with disability is all and fine, but it has a major problem. Namely, disability exists only in the context of people. And while disabled people have many different takes on disability- whether they want to be referred to as disabled, a person with a disability, or forget the labels entirely, whether it matters to them or not, whether they are interested in others with their conditions or not, to what extent they see disability as desirable or otherwise, their political views on disability, and their level of education and interest about their conditions- they almost universally do not want to be seen as their disability.
I understand that.

I have taken to heart one of the pieces of advice I read for how to be a good ally / how to react to transgender people. It recommended that allies not ask the person to explain everything- that they not ask voyeuristic questions- but instead do their own research.

For the most part, I am not tempted to ask people rude questions about their medical conditions and/or disabilities. I don't usually make incorrect assumptions, and for most medical conditions, I know enough that I'm not that curious. For instance, when talking to a friend with cerebral palsy, I'll definitely be paying attention if the person talks about something medical- but I feel like I already know enough about cerebral palsy that I have no inclination to steer the topic in that direction. If the person does mention something I find interesting- for instance, one of my friends with cerebral palsy has an implanted pump made my medtronic- I'll comment (Hey, medtronic is a big maker of insulin pumps- do you know if they're connected?), file the information away for later, and then research it myself.

Occasionally, however, I run into a situation where I'm not sure where the boundaries lie. As a general rule, I don't initiate conversations with strangers about their medical issues (although, since I very frequently initiate conversations with strangers, I often do end up learning about their medical issues). The exception to that is if I guess that a person has diabetes- then I'll mention that I'm diabetic and whatever I noticed that makes me think they are too.
Anyways, I also know that even when somebody else initiates the conversation, various things are off limits. In particular- I don't make any comments on sexual function or development, I tend to assume that asking people about if they had behavioral risk factors will offend, and I do my best to avoid judgments.

But sometimes, particularly online but sometimes in person, a person will ask for my medical advice. And if that person has a disease or disability combination that strikes me as very exciting, and especially if I've no prior knowledge of the person, I have a hard time keeping the disease in the perspective of the person. I know that this disease is not a happy occurrence... but I get excited anyways. And the more I think about, the more excited I get. I know I've helped people to understand their situation medically and some people have even told me that my advice has helped them get diagnoses or improved blood sugar control. That helps- but I still have the problem of the glee. I still have the basic problem of not relating to people. Online, I don't think that usually matters too much since people can easily find somebody else's shoulder to cry on- that can't so easily find somebody to translate medicalese and look up the issues they've got. IRL, I'm not so sure. Should I just say, "This is my Asperger's, I'm not good at supporting people," and move on?

The other problem I have with being a medical geek are feelings of guilt and a sense of not belonging. Why? Because among my reactions to being diagnosed with diabetes was that this was really really cool! I was overwhelmed, scared... but excited! Unlike Asperger Syndrome, which is the sort of thing without a really solid definition, and which people sometimes disbelieve me about having (although other times they guess it even when I don't want them to), diabetes is a well defined enough condition that I can prove that I am diabetic. Although I expected people to disbelieve that I had diabetes in the same way that people react to me saying that I have Asperger Syndrome, this has never happened. The most dramatic reaction people have is to comment on my skinniness in relation to the diabetes- they never really object when I say I have diabetes.
Instead, I found, for a long while, myself objecting. I kept having the feeling that I was an imposter. Any one or two day string of low or normal blood sugars would make me anxious and I'd be somewhat relieved when I had a high reading again.
It took years before I stopped expecting somebody to challenge my diabetes (I think mostly it was time that helped but also the extra things I've had in the past few years). I'm wondering as I type if anybody will challenge me on the basis of this post- I'd guess not.

Recently a woman whose child has a combination of medical diagnoses and unexplained symptoms that fascinate me told me that she wished she was me- she wishes she could read and understand the medical literature like I do. I'm not sure how to respond. I'm not sure it's a good thing to wish for. Not that I'm really, at the end of the day, sorry that this is who I am and what I do- out of the various perseverations I might have had, this one at least can be useful. But it's not a little thing. It's not some small facet of who I am. It's something that makes me very very careful about what I say to her. I know too much and too little, at the same time.

Wednesday, April 13, 2011

Other Health Issues with Diabetes

On Thursday night I had one of those evenings that had better have been teaching me something 'cause it was awful.
As I got home anticipating supper, Dexcom showed 98 with a downwards drift- perfect for supper, right? My folks had already eaten a lot of supper but there were some wonderful leftovers left. I injected and began eating the apple crisp my mother had made. Once I finished the last piece, I started licking the dish.

Then I choked. Now, I have been choking almost on a daily basis for as long as I remember. And usually, like that night, I choke on liquids. But usually it's choke, cough and swallow and then I'm fine. This time? Well, I coughed and coughed and coughed. When my mother asked if I was okay, I couldn't get any words out to say that I was. I drooled all over myself because I couldn't close my mouth while coughing. I threw up a little bit from the force of the coughing. And then... it was over. I could breathe again. My chest was sore, there was vomit in my mouth, but I was breathing.
I felt pretty done with supper, KWIM?

Unfortunately, Dexcom went of right then UNDER 90 showing an 88 angled down. Just lovely. So I sit down and start eating. Half an hour later, my stomach hurts. A lot. My sensor is showing something in the 50s and I'm feeling hypo. Oh boy, I hate this.

Another hour and probably a hundred carbs later, I'm sitting in the 40s with a massive stomach ache. I don't want to ever eat again, thank you very much. My blood sugar begins to rise. It rises by about 1-2 mg/dl per five minutes. That is very slow when your blood sugar is 48 and you've been trying to treat as hypo everything under 90.

My blood sugar continued to rise very slowly until many hours later it was high. I took a couple of units of Novolog and went to bed. I slept through the high alarms. I woke up in the morning feeling stuffed and dehydrated with a blood sugar that was in the mid 300s- apparently it had peaked around 390 at 5 AM. No sharp rises. Just a very slowly digested meal.

In retrospect, I think I should have used a miniglucagon injection.

Speaking of slowly digested meals, I have been on the lansoprazole(prevacid) long enough that if it's not working, it's not going to. So my doctor sent the nuclear medicine department (I remember them- that's where I had my iodine uptake scan and everybody else in the waiting room had cancer) an order for me to have a gastric emptying study. The diagnosis is GERD, which surprised me. I called and asked if they could accommodate a vegan diet- they said yes. I scheduled the study for 8 AM Monday, May 2nd.

Tuesday, April 05, 2011

Tracking Changes (how I think day to day)

I've had some really rough numbers the last couple of weeks. I spent a few hours under 40 during the daytime despite treating the numbers and even signed out of work early for one nasty hypo, and my Dexcom read HIGH for the first time in months (it may have been exaggerating though). My nights were being really erratic.

So I decided to do three things. One, take a laid back approach- don't over react to numbers. Two, switch Lantus injection location. Three, log.

Taking a laid back approach isn't a real change.

Switching Lantus injection location is. When I went on Lantus, the ped endo said it had to be injected in my butt, which idea for some reason made me pretty uncomfortable. But at this point, I've been putting a Lantus injection into my right buttcheek on odd days of the month and into the left buttcheek on even days of the month for 98% of days for about 54 months. Which is a long time. In that time, my butt has kinda disappeared.
I decided to inject the Lantus into my stomach, which is the only other location with a chance of working; my arms get a sort of white lump if I inject more than about two units of Lantus into them at a time (I know this from when I tried splitting the dose), I don't have any place on my legs that I can keep hold of a pinch on while flexing a muscle, and despite my fondness for injecting Novolog into my boobs, I don't make the mistake of thinking that I'm actually injecting into fat there (testosterone took care of that).
I'm giving my butt a break as an injection site for a month. If at that point I want to stick with putting the Lantus into my stomach, I guess I'll start injecting Novolog there, or maybe I'll try wearing a sensor there.

Logging is something I've sort of fallen out of the habit of doing, particularly logging meals, and my current planner doesn't lend itself to it. I'm going to log exhaustively for a week and then give it up again. Hopefully this will lend itself to better ratios. Here's the log:

Saturday evening I injected 10 units glargine.

Overnight I had a hypo that I treated with cookie crumbs (probably about 15 grams of carbohydrate).
At 9 AM my bg was 4.1 mmol (I'm using an mmol meter and a mg/dl Dexcom right now), and I drank an once of apple juice with my lansoprazole.
At 10 AM, sg was 81, I took 6 units aspart and ate 52 grams of flatbread (I estimated that was 25 grams of carbohydrate) with 2 tbsp of hummus (3 grams carbohydrate) and 76 grams of sweet roll which I guessed was 40-50 grams of carbohydrate.
At noon, I was low took three swallows honey.
At 1 PM, I was 71, drank a coconut water box (14 grams of carbohydrate)
At 3 PM, sg was 246, I took one unit aspart
At 5:30 PM, sg was 192 and droppping, took 5 units aspart and ate 23 carbohydrate grams of cake and 92 grams of pizza which I guessed was about 45 grams of carbohydrate.
At 8 PM, sg was 210, ate 202 grams of pizza (estimated this was 100 grams carbohydrate).
At 10 PM, I took 10 units glargine.
At 11 PM, sg was 200, I took one unit Aspart.

At 1 AM, still sg 200, took 1 unit aspart and went to bed.
Overnight, the Dexcom showed a drop to 120 at 5 AM followed by an upwards drift.
Got up at 9 AM to an sg reading 147 and a bg of 7.3 ( = 131.4) had some broccoli with cooking water which I estimated to be about 5 grams carbohydrate. This resulted in a sharp rise.
At 9:40 AM, sg 171 with a 45 degree up arrow, I took 1 unit aspart. Blood sugar peaked around 185 and then dropped.
At 1:40 PM, sg 126 ->, I took 2 units aspart and ate a piece of pizza which I estimated to be 20 grams of carbohydrate. My sensor showed no spike at all but a very gentle rise, and I went high (above 160) at 4 PM.
At 4:35 PM, sg 171 rising, I took 5 units aspart.
At 5:25 PM, sg 161 with an arrow straight down, I ate about 40 grams carbohydrate of cinnamon bread and sweet roll. My blood sugar dropped to about 100, banked, rose to 140, fell gently.
At 8:25 PM, bg 6.8 (122) I took 6 units aspart and ate 3 cups of beans (about 24 grams carbohydrate), 3/4 cups of couscous (about 30 grams carbohydrate), and five frozen strawberries.
At 10:15 PM, I took 11 units of glargine because the trend seemed to have been upwards.

Right now it's half past midnight on Tuesday and my sensor is saying 157-> but showing a slight rise. I'm contemplating taking a unit aspart (Novolog).