complications

1. Eye Damage ("Retinopathy")

2. High Blood Pressure ("Hypertension")

3. Heart Disease ("Coronary Artery Disease")

4. Kidney Failure ("Renal Failure")

5. Erectile Dysfunction

6. Nerve Damage ("Neuropathy")

7. Foot Ulcers/Gangrene

(For additional discussion about complications, check out my "Case of the Month" archive.)

Now before I discuss these complications of diabetes I would like to stress one point. In fact, I think this is the most important point I could ever make about diabetes in general. Complications from diabetes are NOT inevitable. Long gone are the days when if you had diabetes it meant it was just a matter of time until you went blind, went on dialysis or had a foot amputated. Thankfully. Yet I still not infrequently see people whose most vivid impressions of diabetes were gleaned from memories of their mother (or father or aunt or uncle or...) who "had her foot taken off;" with the newly diagnosed person with diabetes sitting beside me terrified it will undoubtedly happen to them, too. Well, I can't guarantee it won't but I can surely make the odds immensely better that it won't. In fact, there is convincing evidence that if someone with diabetes is managed in the best possible way (good lifestyle habits, great blood pressure, great cholesterol, low dose aspirin, etc.), the risk of complications can be reduced by up to 75 percent! (See my Ten Golden Rules of Prevention for the low down on that). Now I wouldn't want to pretend for one second that to achieve these things is easy; in fact it surely is not. But it can be done!

1. Eye Damage ("Retinopathy"): For all intents and purposes when we talk about diabetic eye damage we are talking about injury to the back surface of the eye called the retina and in particular, the small blood vessels that are present there. When retinopathy first starts, these tiny blood vessels become swollen, and they leak a little fluid into the center of the retina. The person's sight usually isn't much affected by this (The absence of symptoms does not mean that "everything must be okay"-hence the need to have regular eye doctor appointments). This condition is called background retinopathy. Often things never progress beyond this stage. But, if they do, the next stage is when tiny blood vessels grow out and across the eye. This is called neovascularization. The vessels may break and bleed into the clear gel that fills the center of the eye, blocking vision. Scar tissue may also form near the retina, pulling it away from the back of the eye. This stage is called proliferative retinopathy, and it can lead to impaired vision and even blindness. The images below (click to enlarge) detail the stages of eye damage as seen by a doctor looking into your eyes with an ophthalmoscope. Please remember what I said...eye damage is not inevitable:

Question: How do I avoid this complication?

Answer: It is very, very well established that the better the glucose control, the lesser the risk of eye damage. What is more recently established is that high blood pressure, high (LDL) cholesterol and smoking are also major risk factors for retinopathy. So we aim for blood sugars and blood pressure and cholesterol readings as good as possible (and we do our best to quit smoking!). Sound like a tired refrain? Perhaps, but these measures are crucial. See my Top Ten Page to find out what optimal target blood sugar and optimal blood pressure readings are. More information on diabetic retinopathy.

Oh, and let me add one other important point. If someone has had very poor blood sugars and their sugars are then brought rapidly down to normal, it changes the way the light bends through the lens of the eye. And that causes blurred vision. This corrects over a few weeks. So if you have newly diagnosed diabetes and, after being started on treatment you find your vision to have suddenly become blurry, this is often, believe it or not, a good sign...it means your sugars are on they way down. Incidentally, don't waste your money on expensive prescription glasses the day you get diagnosed as having diabetes. Buy some cheapo pair off the shelf for a few bucks. Once your sugars have been stable for a few weeks, your vision will likely return to its usual state and then you can determine if you truly need some expensive prescription glasses. But remember, it is crucial if you have newly diagnosed diabetes that you see a good eye doctor to make sure there is nothing more seriously amiss (as shown in the photos above).

2. High Blood Pressure ("Hypertension"): I wish I could tell you the reason you might have high blood pressure. Of course, the idea of being a Nobel laureate surely is appealing. The truth of the matter is, in ninety-five per cent of cases we ("we" meaning us doctors) don't find a cause. Not that there isn't a cause; it's just that we don't find one. The five per cent of cases that we do "solve" are usually in very young or very old people who have conditions such as a blocked artery to a kidney or others who have unusual hormone disorders and other rare diseases. Now whereas we don't often know what the cause of hypertension is, we do know what the risk factors are. And we do indeed know how to treat it. For more info on this click here to go to my page on anti-hypertensive therapy.

Question: How do I avoid this complication?

Answer: Often it is not avoidable. Nonetheless, you can improve the odds of avoiding it (or, if it present, lessen its severity) by making sure you try your best to achieve and maintain a good weight, that you do not consume excess salt (sodium) or alcohol, that you exercise ("cardio" stuff such as walking, jogging, swimming, biking, etc.) regularly (aim for twenty to thirty minutes at least two to three times per week; even better if it's five or more times per week), that you don't smoke and basically, follow common-sense lifestyle measures. Though these things all help, most people with high blood pressure do end up requiring medication in order to achieve optimal (that's what we're after...optimal, not just "okay") blood pressure. See my Top Ten Page to find out what optimal blood pressure readings are. More information on high blood pressure.

3. Heart Disease ("Coronary Artery Disease"): There are several different forms of heart disease that people with diabetes are prone to, but far and away the most prevalent is blockage due to a build-up of cholesterol inside the (coronary) arteries (these are the arteries that feed oxygen to the heart muscle). The following images can be enlarged by clicking on them:

Question: How do I avoid this complication?

Answer: Unlike eye damage or kidney damage, heart troubles are less closely linked to good sugar control. More important are co-existing risk factors such as (excuse me for sounding like a broken record [gee; I wonder how many people born since 1990 know what that expression means?]) smoking, high blood pressure, high cholesterol, a sedentary lifestyle, and so on. Genetic factors also play a role. If, for example, your father had a heart attack at the age of forty, it puts you at higher risk. But remember, this complication is not inevitable. Modify your reversible risk factors and you've improved your odds immeasurably! In many cases aspirin (ASA) will help to prevent a heart attack from developing (even though it doesn't prevent cholesterol build-up inside an artery, it does help to prevent blood clots from forming inside the narrowed blood vessel and clogging it off altogether [which is what leads to a "heart attack"]). There is also mounting evidence that taking medicines called ACE inhibitors may help prevent heart attacks in people with diabetes. It is not yet routine that any and all people with diabetes are automatically placed on ACE inhibitor medication, but it may well evolve that way in the near future. More information on heart disease.

4. Kidney Failure ("Renal Failure"): As most people know, the kidneys "purify" the blood. They remove certain substances from the body and control salt and fluid balance. If left untreated, kidney failure leads to swelling ("edema"), inflammation of certain body tissues and, ultimately, coma and death. Please note that I said "untreated." My goal for my patients with diabetes is to try my utmost to keep this purely a hypothetical concern. Much better to prevent kidney failure in the first place, rather than simply dealing with its fallout. The earliest evidence of kidney malfunction is the presence of excessive albumin (a form of protein) in the urine. This is determined by doing a urine microalbumin test and it is crucial that this test be done regularly. Incidentally, despite popular wisdom to the contrary, diabetic renal disease does NOT cause back pain.

Question: How do I avoid this complication?

Answer: Medical studies show definitively that kidney malfunction can often be avoided. They key to success? Optimal blood sugar control and optimal blood pressure control. We don't want to settle for "adequate" or "okay" or "good" control. We should strive for optimal. That may take greater effort and may take more medication, but if it avoids kidney failure and dialysis, most people would feel that the trade-off is well worth it. See my Top Ten Page to find out what optimal target blood sugar and optimal blood pressure readings are. Additionally there is proof that even if you already have kidney malfunction, so long as it is reasonably early on, progressive damage can often be halted (or even reversed) by taking medications known as ACE inhibitors ("Angiotensin Converting Enzyme inhibitor") or ARB's ("Angiotensin Receptor Blockers; also known as Angiotensin 2 blockers or AT blockers). More information on ACE inhibitors. More information on ARB's. It is not yet known if taking these medicines before there is any evidence of kidney problems will prevent their development, but there is increasing evidence pointing that way and it may well be that in the near future once you are diagnosed as having diabetes it becomes automatic that one of these agents is prescribed. Incidentally, If you have significant kidney damage it is important to note that a high protein diet can be harmful (and indeed, a low protein diet is sometimes prescribed). More information on diabetic kidney disease.

5. Erectile Dysfunction: Many men with diabetes develop sexual difficulty. Sometimes this manifests as less rigid erections, sometimes as a complete inability to achieve any sort of erection and sometimes erections are normal, but ejaculation is not accompanied by the normal release of semen ("retrograde ejaculation"). Therapy for erectile dysfunction is available, as most people know from watching the plentiful television commercials that grace the air waves (I guess I'm showing my age again...that should have been the television commercials that grace the cable connections). Indeed, there are many different therapies out there, Viagra (and similar drugs such as Cialis and Levitra) being but one option. Other forms of treatment include use of a vacuum pump (probably quite an underused therapy considering how simple and safe it is), injections of medicine directly into the urethra or alternatively injected directly into the tissue of the penis (sounds unpleasant, but actually tolerated very well and quite an effective therapy). There is an excellent (no, I'm not being self-congratulatory-I didn't create the presentation) multimedia presentation on erectile dysfunction and treatment (when the page loads, click on "go to module" button).

Question: How do I avoid this complication?

Answer: I'm sorry for sounding redundant but...this too is caused by poor sugar control. So, the goal is to optimize blood glucose levels. Smoking is also a contributory factor-just like the new cigarette package labelling says (in Canada anyhow).

6. Nerve Damage ("Neuropathy"): There are quite a number of different forms of nerve damage that can occur in diabetes, but for all intents and purposes the one type that people with diabetes are most likely to develop is called "peripheral neuropathy" and manifests as a feeling of numbness or discomfort that begins in the toes and, as it progresses, slowly starts to involve the feet. At times, it can be a very, very uncomfortable or even painful feeling. Checking the feet with what is called a "monofilament" is very helpful in assessing for possible neuropathy. See the section below ("foot ulcers/gangrene") for more info on monofilaments. Treatment is, I'm sorry to say, often not all that effective. Fortunately there is lots of research being done (particularly by Dr. Vera Bril in Toronto) on this troublesome problem and hopefully better therapies will emerge in the not too distant future. Meanwhile we do have quite a number of different medicines available. If the affected area is small in size then local therapy with capsaicin may be of value. If the affected area is larger, then oral medication is generally necessary. The drugs most commonly used include amitriptyline (Elavil), Neurontin and Lyrica.

Question: How do I avoid this complication?

Answer: I'm sorry. I hate to sound redundant again and again and again, but...once again we are talking about good (actually not just good, but the best possible) sugar control.

7. Foot Ulcers/Gangrene: This is perhaps the most dreaded of complications from diabetes; yet in some ways one of the most avoidable. The two main factors leading to foot ulcers are poor circulation and poor nerve functioning. Poor circulation is a result of a combination of (usually correctable) factors including high cholesterol, smoking, poor blood sugar control...basically the same things that lead to coronary artery disease. Poor nerve functioning ("neuropathy") is discussed above. One of the best ways to determine if someone's foot is at risk for ulceration is to test whether someone can feel a light touch applied to the foot with what is called a ten gram monofilament (after you click this link wait a few seconds and an animation will start). This is a pain-free test! You can obtain your own monofilament through the LEAP program web site. So then, a...

Question: How do I avoid this complication?

And an answer: Control your sugars, control your cholesterol and so on and so on. BUT and this is a big but, that is not enough. Foot ulcers can still develop. So what you also have to do is carefully inspect your feet on a daily basis. If you see areas of skin breakdown or inflammation and most definitely if you see even a hint of ulceration, see your health care provider promptly. If you have a hard time getting a good look at the bottom of your feet, ask a loved one to look for you. Alternatively, use a flexible mirror. Most such mirrors are not very good, but at the Canadian Diabetes Association meetings in October, 2004 I finally came across one that I liked (pictured right). It's got a big mirrored surface, a bright light and seems very well made. It's available on-line at Diabeaters. (Incidentally, I have no financial - or other - relationship with this company and mention this only as a 'for your information;' not as an endorsement.)

This photo shows an example of an ulcer of a big toe.

Good, properly-fitting foot wear is essential in helping prevent foot ulcers. Also, have your physician and diabetes educator check your feet regularly. And see a podiatrist or chiropodist if necessary (for example if you have troublesome calluses or problems with your toenails and so on).

One skin condition which people with type 1 diabetes sometimes get (usually on the shins, but sometimes on the top surface of the feet) is called necrobiosis lipoidica diabeticorum (Wow; what a mouthful, eh?) or, for short, just "necrobiosis" but that isn't short enough or pronounceable enough so we usually just call it NLD. NLD consists of reasonably small, shiny, somewhat yellowish patches on the skin;, sometimes resembling a polished surface. It's not dangerous and its importance is almost always just cosmetic. Treatment is seldom required and it often fades with time. More info including a photo.