First, thank you all for your interest in my first attempt -I received very thoughtful and useful (to me) responses.
I would next like to speak to you about diabetes. There are several reasons for this – first, there is tremendous media attention to this issue currently, with a flavor that this is a new occurrence, that a previously uncommon condition is now becoming epidemic, that this is very dangerous, and so on. Second, there is also an undercurrent of suggestion that if we lost some weight, did more exercise like funky dancing in doctor’s waiting rooms, changed school lunches, taxed soda pop, etc., we would stop this trend (and conversely that if we don’t we will die, lose our sight, limbs, yada yada). Third, of the people for whom I am their physician and adviser, I would guess about 30% (maybe more) actually have diabetes, and so I spend a lot of time thinking about it.
This is actually a very complex issue, and therefore I would like to approach it in three parts: first, definitions and history; second, current diagnosis and treatment; third, complications. To do otherwise would take me too long to do all at once, and you too long to read.
I am first going to do what is most like an annotated glossary. I am going to organize is by topic, as opposed to alphabet.
Diabetes was first described, and named, in the west, by Hippocrates about 5000 years ago. He noted a disease in which people became very thirsty, urinated prolifically, lost weight rapidly, and then died. He thought this was a condition in which flesh was converted to water (he was not far off), and named it diabetes, which referred to a siphon. Using the only lab available to him, he noted that the urine was sweet to the taste, and elaborated it as “mellitus”, a referral to honey.
In 1889, Dr. Oskar Minkowski noted that extirpating the pancreas in dogs caused an immediate and lethal form of diabetes. In 1900, Dr. Eugene Opie, a pathologist, noted that in autopsies of people who died of diabetes (we would call them type 1), the structures in the pancreas called Islets of Langerhans had been destroyed. Dr. Opie suggested that this might have caused the problem. In 1922, Dr. Frederick Banting, with the assistance of the second year medical student (later doctor) Charles Best, managed to extract a substance from the pancreas (insulin), demonstrated that administering this extract completely reversed the issue in dogs, and won the Nobel prize (Mr. Best got nothing).
DIABETES MELLITUS (from now on I will only refer to it as diabetes)
There are several different types of diabetes, all with different implications.
What they all have in common is a measured blood glucose greater than some reference number (this number is arbitrarily defined).
Type I diabetes (Juvenile onset diabetes; ketosis prone diabetes)
This is a relatively uncommon form of diabetes, but the worst. It most commonly manifests itself in children, 7 years old, on up. It can present in young adulthood. It is caused by the total absence of insulin (I will define insulin later) – think Dr. Minkowski’s dogs. This can happen for several reasons: surgery with resection of the pancreas, trauma with destruction of the pancreas, toxin (streptozoticin, a cancer treatment; there was also a rodenticide, not available for 50 years, that did this; could also be possibly caused by infection with a virus) - but most commonly this is an autoimmune disease, with immune destruction of the islet cells. This is sporadic, not familial, and is marked by the condition known as ketoacidosis.
In this situation, without insulin, the cells of the body are not able to use glucose as a fuel. They need to turn to something else, and the liver decided on fat. Rather than moving the fat through the usual slow metabolic pathways we use to lose weight when we diet, the victim begins to process fat very rapidly, producing a number of organic acids as a byproduct. These are produced in huge amount, more than the body can metabolize, and the blood becomes increasingly, rapidly acidic.
This, in turn, causes many different serious metabolic derangements, and the person presents to the emergency room with shock, acid blood, hyperventilation, and low potassium. In lethal cases they are comatose. All of this is actually fairly easy to correct by giving them fluids and insulin and paying attention to their electrolytes (defined later), but it can be pretty scary.
I have managed MANY people with this problem, and the most common cause is that they stopped taking their insulin. Insulin is the only treatment for this condition.
Type II diabetes
In type II diabetes, the person is actually producing insulin. In a large percentage of cases they are actually producing more insulin that the normal person is, but they have become resistant to its effect. Insulin acts by binding to a receptor of the surface of a cell. This changes the receptor, which then catalyzes a second response in the cell, which makes the cell permeable to glucose (this is simplified, but I myself don’t understand the biochemical complexities after the receptor binding). People with type II diabetes are older, usually middle age or older, frequently have no symptoms, and are discovered with random screening or by accident. They do not feel ill because of their elevated blood sugars, neither do they feel better if the sugars are lowered.
There are several subsets of type II diabetes:
Symptomatic – “Hey, Doc – look how good I’m doing! After all these years, I am finally losing some weight.”
OK, what are you doing differently? Nothing much, but now it is working? Well, usually this means that the person has developed what Hippocrates described. In the absence of adequate functional amounts of insulin, the body is raising the blood sugar to drive some across the cell membranes anyway. This has happened slowly, so no acidosis results. However, between the calorie loss as sugar in the urine, and the need to have very high blood sugars, what the person is eating is not enough, and they are losing body mass. This person is not really very far away from having acidosis, it would happen if they were stressed in any way, and they will need insulin. Frequently, this person will complain of increased thirst, increased urination, hunger, blurred vision (due to very high sugars). They will usually need insulin.
Symptomatic B – no weight loss, but complaints of fatigue (like the rest of us), urination, thirst. In the trade, these are called “polys” – polyuria, polydipsia, polyphagia (urinating, drinking, eating). These people may be able to get by with oral agents.
Asymptomatic – these people feel fine, they were found to have an abnormal blood glucose by screening, incidental finding etc. I once saw a man having his blood sugar checked at the state fair, while eating cotton candy (what could that result mean?). These people need to have the sugar checked again in a somewhat controlled environment. Whether or not they have diabetes is then a matter of fairly arbitrary definition.
Diabetes of the elderly – this is a situation in which a non-disease is labeled a disease. The demographers tell me that of all people over the age of 80 that have ever lived on earth, greater than 90% are alive now. The medical profession knows very little about these people, particularly the relatively healthy ones. What SHOULD the fasting blood sugar be in a healthy 85 year old? If it is higher than an 19 year old, does that mean the older person has a disease? Do they need to be treated in the same way? Does the use of several pharmaceuticals in them, as you might do with the young person, decrease or increase their overall risks?
The current guideline for diagnosis and treatment of diabetes ignores the question of what is normal in older people, and makes no distinction in treatment recommendations. Physicians can use their judgment about these things - but the guidelines and “performance pay” systems ignore these issues, reward treatment, not judgment, and do not systematically look at outcomes.
Stress diabetes – since diabetes is defined by ever having a blood sugar outside of the diagnostic range, there are a large number of people labeled diabetic because of high blood sugars related to serious stress condition. I don’t mean your dog died, the truck broke down, your girlfriend ran off, etc. – I mean septic shock (35% mortality), major heart attack, terrible traffic accident with several emergency surgeries – that sort of thing.
EVERYBODY in this situation has elevated blood sugars 200-400. The treatment for that is in flux (I’ll get to that later), but it certainly does not mean the person has diabetes. Yet, since the definition only requires you to have an elevated blood sugar once, if some doctor puts this on your discharge summary or a bill to an insurance company, you are marked as diabetic forever. It is almost impossible to get this diagnosis off your record. Being cynical, I suspect the insurance companies like it this way – they can charge you more, and also consider anything in the future that might remotely be related to diabetes a “pre-existing condition” for which they can deny coverage.
Gestational diabetes – there are some women who have normal blood sugars usually, but will develop higher blood sugars during pregnancy. This is actually an important thing to know, as this leads to higher birth weight babies (too much of a good thing), a higher incidence of birth defects, and a higher incidence of still births. These women are treated for their blood sugars during pregnancy, and they usually revert to normal after giving birth. They may be at a higher risk of developing diabetes in the future, but this does not inevitably happen.
Metabolic syndrome – these people are usually men. They are fat, with most of the fat being central (big bellies). They will have non-ketotic diabetes, sometimes quite resistant to treatment, high blood fats, hypertension – they tend to have macrovascular disease (again, more on that later). This is very common. The best diagnostic tool for it is actually a tape measure – increased abdominal girth is universal with this condition.
Mixed type – there are a number of people who seem to have type II diabetes, who will suddenly develop ketoacidosis. They are usually not obese, 50′ish in age, no particular inciting event. Many type II diabetics will develop mild ketosis with stresses such as pneumonia (stress makes you more insulin resistant), but this subset seem to develop ketoacidosis with no provocation. They are frequently C-protein absent or low (more later about C protein).
Hyper-osmolar state – this is actually a complication, but there are people who present with this. They have a combination of VERY high blood sugars (think syrup), and dehydration, they present usually comatose. They have enough insulin effect to prevent acidosis, but not to prevent these extraordinary sugars. They are usually elderly, and, if you are careful, usually do well, although they have a couple of days of ICU time.
In general, type II diabetes is more frequently familial than type I, particularly the obesity-related subsets of type II.
I have probably left out one or two types -I once saw a young man, age about 24, who developed type 1 diabetes the year before – he was a boiler crewman on a naval destroyer – he told me that three other young men in the same crew developed the same thing over a period of about 3 months – How do you classify him?
I will continue this – next time, I will describe the diagnostic criteria, tests and med type used for this disease.