The Nutrition Debate #98: The “Dreaded Complications” (of Type 2 Diabetes)

With the meteoric rise in the incidence of Type 2 Diabetes and obesity (“diabesity”, in the contemporary parlance), and their associated public health implications, the “dreaded complications” of the pandemic should now be front-and-center in the news. They do deserve our attention, and I’m not sure whether I am just blocking them out of my consciousness or that in fact they are not being widely aired.  Of course, they are pretty scary, and fear is a good motivator, but that is not the purpose of this post. I just want to put the facts “out there” so it cannot be said that I have swept the chronic complication of Type 2 diabetes “under the rug.”

Let’s begin with this truthful but hopeful note from the American Diabetes Association: “Diabetes increases your risk for many serious health problems. The good news? With the correct treatment and recommended lifestyle changes, many people with diabetes are able to prevent or delay the onset of complications.” I think this last sentence is actually a gross understatement. Given the current treatment protocols recommended by the ADA, however, I am not surprised that their hopefulness is so qualified. I would go much further, as regular readers here know. I say that a Type 2 who follows a Very Low Carbohydrate diet can avoid the complications altogether. However, if you do not control your blood sugar by diet or other means, the NIH’s Medline Plus site tells us this: “If you have diabetes, your blood sugar levels are too high. Over time, this can cause problems with other body functions, such as your kidneys, nerves, feet, and eyes. Having diabetes can also put you at a higher risk for heart disease and bone and joint disorders. Other long-term complications of diabetes include skin problems, digestive problems, sexual dysfunction, and problems with your teeth and gums.”

To give the reader a sense of scale, the order of magnitude of the leading risks of complications of chronic Type 2 diabetes are described in this Wikipedia entry:  “In the developed world, diabetes is the most significant cause of adult blindness in the non-elderly and the leading cause of non-traumatic amputation in adults, and diabetic nephropathy is the main illness requiring renal dialysis in the United States” (emphases all mine). The medical terms for these chronic complications are diabetic retinopathy, diabetic neuropathy, and diabetic nephropathy. All of these complications are directly associated with Type 2 diabetes, and they are all the result of damage to the small blood vessels. This damage leads to a microangiopathy which can also damage the heart. The result is diabetic cardiomyopathy, a diastolic dysfunction that eventually leads to heart failure, according to Wikipedia.

Another complication of chronically elevated blood glucose is macrovascular disease, which leads to cardiovascular disease (CVD). Wiki lists the following examples: Coronary artery disease (CAD), leading to angina or myocardial infarction (“heart attack”); diabetic myonecrosis (”muscle wasting”); peripheral vascular disease, which contributes to intermittent claudication (exertion –related leg and foot pain) as well as diabetic foot; and stroke (mainly the ischemic type).

In addition, Diabetic encephalopathy, the increased cognitive decline and risk of dementia – including Alzheimer’s disease – is observed in and associated with chronically elevated blood sugar, i. e. inadequately controlled Type 2 diabetes. And these are just some of the risks! But I said I wasn’t going to scare the living bejesus out of you, so let’s end on an up note.

 An abstract presented at a poster session of the ADA meeting in Philadelphia in June 2012 is apt. It reported a Swedish observational study of 12,359 patients with poorly controlled Type 2 diabetes. None of the patients had any cardiovascular or coronary heart disease at baseline. The patients averaged 62 years of age with mean disease duration of 9 years. The average baseline HbA_1c was 7.8% and their mean body mass index was 30. Their mean blood pressure was 140/78. 62% were taking antihypertensive (blood pressure) meds and 46% were on lipid-lowering (cholesterol) drugs.

After 5 years, the study’s investigators separated the patients into 2 groups: those whose HbA_1c decreased by at least 1% over the 5 years (6,841) and those whose HbA_1c remained stable or increased  (5,518). At the study’s conclusion the mean HbA_1c was 7% in the improved-control group (-0.8%) and 8.4% in the poorly controlled group (+0.7%), they reported.

By then, 12% of the well-controlled group and 20% of the poorly controlled group had developed coronary heart disease (CHD). Cardiovascular disease (CVD) was present in 17% of those in the well-controlled group and 30% of the poorly controlled group. And all-cause mortality was 15% among the group with no improvement in HbA_1c and 10% in the group with improved HbA_1c. Thus, after adjusting for baseline risk factors and treatment changes during the study period, they concluded that “patients who had suboptimal glycemic control and reduced their HbA_1c value by slightly less that 1% were 50% less likely to die within 5 years than were patients whose HbA_1c did not improve…” A study team presented similar results at the annual meeting of the European Association for the Study of Diabetes (EASD) in Sept 2012, as reported here.

So, with improvement in HbA_1c of less than 1% (7.8 to 7.0%) and an average blood glucose level of 154, there is still a 50% benefit. I wonder what the benefit would be for a 2% or even a 2.5% improvement in A1c? Would the increased risk of cardiovascular disease, coronary heart disease, and all-cause mortality be eliminated completely? It’s something you might want to think about.