Category Archives: Diabetes Complications

Is Alzheimer’s Disease Caused By Type 2 Diabetes?

dementia, memory loss, Mediterranean diet, low-carb diet, glycemic index, dementia memory loss

“More basic research is critical.”

Several scientific studies, but not all, link type 2 diabetes with Alzheimer’s disease. Some go so far as to say Alzheimer’s is type 3 diabetes.

My Twitter feed brought to my attention a scientific article I thought would clarify the relationships between diabetes, carbohydrate consumption, and Alzheimer’s dementia (full text).

It didn’t.

Click the full text link to read all about insulin, amylin, insulin degrading enzyme, amyloid–β, and other factors that might explain the relationship between type 2 diabetes and Alzheimer’s dementia. You’ll also find a comprehensive annotated list of the scientific studies investigating the link between diabetes and Alzheimer’s.

Bottom line: We still don’t know the fundamental cause of Alzheimer’s disease. A cure and highly effective preventive measures are far in the future.

Action Plan For You

You may be able to reduce your risk of Alzheimer’s disease by:

  • avoiding type 2 diabetes
  • preventing progression of prediabetes to diabetes
  • avoiding obesity
  • exercising regularly
  • eating a Mediterranean-style diet

Scientists have no idea whether a Stone Age diet prevents dementia.

Carbohydrate restriction helps some folks prevent or resolve obesity, prediabetes, and type 2 diabetes. A low-carb Mediterranean diet is an option in my Advanced Mediterranean Diet (2nd edition).

Steve Parker, M.D.

Reference: Schilling, Melissa. Unraveling Alzheimer’s: Making Sense of the Relationship Between Diabetes and Alzheimer’s Disease. Journal of Alzheimer’s Disease, 51 (2016): 961-977.

 

 

 

Natural Versus Drug Therapy for Metabolic Syndrome

"These are flying off the shelves!"

“But selling drugs is good for the economy!”

Have you heard that 60% of adults in the U.S. are taking prescription drugs? That’s up from 50% a decade ago. UPI has the pertinent details. A snippet:

Many of the most used drugs reflect the effects of metabolic syndrome, a group of conditions tied to obesity and diet.

“Eight of the 10 most commonly used drugs in 2011–2012 are used to treat components of the cardiometabolic syndrome, including hypertension, diabetes, and dyslipidemia,” researchers wrote in the study, published in the Journal of the American Medical Association. “Another is a proton-pump inhibitor used for gastroesophageal reflux, a condition more prevalent among individuals who are overweight or obese. Thus, the increase in use of some agents may reflect the growing need for treatment of complications associated with the increase in overweight and obesity.”

I’m not anti-drug, generally. Lord knows I prescribe my fair share. But in addition to the cost of drugs, we have side effects and drug interactions to worry about. If we in the U.S. would effectively attack overweight and obesity, we’d be much better off.

But it’s a lot easier to just pop a pill, isn’t it?

Especially if someone else is paying for the pill.

Steve Parker, M.D.

Is the Hemoglobin A1c Test Always Accurate?

From 97 to 90 mg/dl

Not the only way to assess glucose control

Can you believe I’ve had patients show me a week’s worth of home glucose tests showing great numbers, tell me they’ve been that good for the last three months, and then I find a sky high Hemoglobin A1c test? How can that be?

Hemglobin A1c (or HgbA1c) is a standard measure of glucose control, or lack thereof, over the three months preceding the blood test.

It’s also used for diagnosis of diabetes and prediabetes. Levels between 5.7 and 6.4% suggest prediabetes. Levels of 6.5% of higher indicate diabetes.

Hemoglobin is the oxygen-carrying protein in red blood cells. HgbA1c tells us if many sugar molecules are stuck to the hemoglobin, a process called glycosylation. HgbA1c is sometimes referred to as glycated hemoglobin. About half of the HgbA1c value is determined by blood sugar levels in the month before the blood draw.

But the HgbA1c test is not always an accurate reflection of blood sugar levels.

Many factors unrelated to serum glucose (sugar) levels can alter the HgbA1c value. Here they are:

Pregnancy

Pregnant women tend to have lower than average HgbA1c.

 

Certain Types of Anemia

Iron-deficiency anemia may yield falsely low or high HgbA1c, depending on whether it’s being treated or not.

Acute bleeding and hemolytic anemia give falsely low HbA1c values.

The unifying feature here is that young red blood cells, called reticulocytes, take some time to get glycosylated.

Lack of a Spleen 

HgbA1c will be falsely high. Your spleen removes old red blood cells. Not having a spleen increases the life span of red blood cells, so they can accumulate more glucose molecules.

Various Hemoglobin Types or Congenital Abnormalities

Hemoglobin S and hemoglobin C may lead to deceptively low HgbA1c. Hemoglobin F tends to overestimate.

Blood Transfusions

Recent red blood cell transfusions will lower the HgbA1c if it was elevated to begin with, especially if lots of blood is transfused.

Renal Failure

It’s complicated; talk to your kidney specialist.

Chronic Disease

HgbA1c values can be unreliable in chronic alcoholism, chronic narcotic users, severely high triglyceride or bilirubin levels, kidney failure, vitamin and mineral deficiencies (particularly the vitamins and minerals needed to make red blood cells).

Race

Hispanics, Asians, and Blacks tend to have higher HgbA1c’s than Whites who have the same blood sugar levels. The difference is about 0.3% (absolute, not relative.

Wild Glycemic Excursions

What’s this? You might call it labile diabetes: dramatic swings between sugars too low and way too high. For example, this patient may have daily glucose swings between 40 and 210 mg/dl (2.2  and 11.7 mmol/l). His HgbA1c may turn out near normal or acceptable, but many experts worry that the wild oscillations may contribute to diabetic microvascular complications like eye and kidney disease.

Are There Alternatives to HgbA1c?

Yes. If you think the HgbA1c test is inaccurate, consider other tests such as continuous glucose monitoring, fructosamine, glycated albumin, 1,5-anhydroglucitol, and more frequent home glucose monitoring.

Steve Parker, M.D.

Reference: Bazerbachi, F., et al. Is hemoglobin A1c an accurate measure of glycemic control in all diabetic patients? Cleveland Clinic Journal of Medicine, vol. 81, #3, March 2014: 146-149

Do You Have Hypoglycemia Unawareness?

Steve Parker MD

Watch out for hypoglycemia particularly if you exercise vigorously and take drugs with the potential to cause hypoglycemia, like insulin and sulfonylureas

If you take drugs that can cause hypoglycemia, you need to know about “hypoglycemia unawareness.” (Click for a quick review of diabetes drugs.)

Some people with diabetes, particularly after having the condition for many years, lose the ability to detect hypoglycemia just by the way they feel. This hypoglycemia unawareness is obviously more dangerous than being able to detect and treat hypoglycemia early on. Blood sugar levels may continue to fall and reach a life-threatening degree.

Hypoglycemia unawareness can be caused by impairment of the nervous system (autonomic neuropathy) or by beta blocker drugs prescribed for high blood pressure or heart disease. It’s more common in folks who have had diabetes for many years. People with hypoglycemia unawareness need to check blood sugars more frequently, particularly if driving a car or operating dangerous machinery.

Steve Parker, M.D.

Sulfonylurea Drugs Linked to Heart Disease in Women

…according to this article at Diabetes Care. The study population was the Nurses Health Study. The longer the sulfonylurea was used, the stronger the association with Coronary Heart Disease. CHD is by far the most common cause of heart attacks. On the bright side, the drugs were not linked to stroke risk. Remember, correlation is not causation, blah, blah, blah…

This report is another reason to do all you can to control blood sugars with diet and exercise, minimizing the risks—known and unknown—of long-term drugs.

I rarely start my patients on sulfonylureas these days.

Steve Parker, M.D.

Pioglitazone May Prevent Dementia

MP900178842[1]

Pioglitazone (aka Actos) is a type 2 diabetes drug in the TZD class. You could call it an “insulin sensitizer.” A recent report out of Germany suggests that pioglitazone prevents dementia, but it’s not a very strong linkage. If it works, I wonder if it’s simply related to better control of blood sugar, which could be accomplished with a variety of means. 

The best popular press report I’ve seen is at Bloomberg.

German researchers went fishing for associations in a huge database of patients and drug usage. Their formal report hasn’t even been published yet. A five-year study was recently initiated to further investigate the possibility that piogoitazone prevents dementia. I doubt this will pan out.

Steve Parker, M.D.

David Spero, RN, Makes the Case for Tight Blood SugarControl

at Diabetes Self-Managment.

Steve Parker MD, paleobetic diet,

Reduce retinopathy risk with good blood sugar control

David writes:

Two famous studies showed that tight control of glucose did not cause a statistically significant reduction in heart attacks or early death. But roughly 20 years after the studies ended, tight control subjects are living longer and healthier than those who were in the comparison groups.

Those two famous studies, however, did originally show evidence of better eye, nerve, and kidney function via good control.

Steve Parker, M.D.

PWDs (Diabetics) Having Fewer Heart Attacks, Amputations, and Strokes

MedPageToday has the details. This jibes with my experience over the last 30 years. A quote:

An analysis of national data found that rates of myocardial infarction (MI) in diabetic patients dropped about 68%, and amputation rates were halved between 1990 and 2010, Edward Gregg, PhD, of the CDC in Atlanta, and colleagues reported in the April 17 issue of the New England Journal of Medicine.

Strokes and deaths from hyperglycemic crisis also fell dramatically.

The number of adults reporting a diagnosis of diabetes more than tripled during the study period.

Steve Parker, M.D.

Eat Nuts to Reduce Cardiovascular Risk and Improve Type 2 Diabetic Blood Sugars

Paleobetic diet

Macadamia nuts on the tree

Most of the diets I recommend to my patients include nuts because they’re so often linked to improved cardiovascular health in scientific studies. Walnuts are associated with reduced risk of type 2 diabetes in women, and established type 2 diabetics see improved blood sugar control and lower cholesterols when adding nuts to their diets.

paleobetic diet, diabetic diet, low-carb diet

Apples, pecans, and blueberries: So simple even a redneck can make it (I are a redneck)

Nut consumption lowers total and LDL cholesterol levels, and if triglycerides are elevated, nuts lower them, too. Those changes would tend to reduce heart disease.

Conner Middelmann-Whitney has a good nutty article at Psychology Today.

Steve Parker, M.D.

Reference: Joan Sabaté, MD, DrPH; Keiji Oda, MA, MPH; Emilio Ros, MD, PhD. Nut Consumption and Blood Lipid Levels: A Pooled Analysis of 25 Intervention Trials. Archives of Internal Medicine, 2010, Vol. 170 No. 9, pp 821-827. Abstract:

Background  Epidemiological studies have consistently associated nut consumption with reduced risk for coronary heart disease. Subsequently, many dietary intervention trials investigated the effects of nut consumption on blood lipid levels. The objectives of this study were to estimate the effects of nut consumption on blood lipid levels and to examine whether different factors modify the effects.

Methods:  We pooled individual primary data from 25 nut consumption trials conducted in 7 countries among 583 men and women with normolipidemia and hypercholesterolemia who were not taking lipid-lowering medications. In a pooled analysis, we used mixed linear models to assess the effects of nut consumption and the potential interactions.

Results:  With a mean daily consumption of 67 g of nuts [about 2 ounces or 2 palms-ful], the following estimated mean reductions were achieved: total cholesterol concentration (10.9 mg/dL [5.1% change]), low-density lipoprotein cholesterol concentration (LDL-C) (10.2 mg/dL [7.4% change]), ratio of LDL-C to high-density lipoprotein cholesterol concentration (HDL-C) (0.22 [8.3% change]), and ratio of total cholesterol concentration to HDL-C (0.24 [5.6% change]) (P < .001 for all) (to convert all cholesterol concentrations to millimoles per liter, multiply by 0.0259). Triglyceride levels were reduced by 20.6 mg/dL (10.2%) in subjects with blood triglyceride levels of at least 150 mg/dL (P < .05) but not in those with lower levels (to convert triglyceride level to millimoles per liter, multiply by 0.0113). The effects of nut consumption were dose related, and different types of nuts had similar effects on blood lipid levels. The effects of nut consumption were significantly modified by LDL-C, body mass index, and diet type: the lipid-lowering effects of nut consumption were greatest among subjects with high baseline LDL-C and with low body mass index and among those consuming Western diets.

Conclusion:  Nut consumption improves blood lipid levels in a dose-related manner, particularly among subjects with higher LDL-C or with lower BMI.

Exercise and the PWD (Person With Diabetes)

hypoglycemia, woman, rock-climbing

Hypoglycemia now would be a tad inconvenient

People with diabetes may have specific issues that need to be taken into account when exercising.

DIABETIC RETINOPATHY

Retinopathy, an eye disease caused by diabetes, increases risk of retinal detachment and bleeding into the eyeball called vitreous hemorrhage. These can cause blindness. Vigorous aerobic or resistance training may increase the odds of these serious eye complications. Patients with retinopathy may not be able to safely participate. If you have any degree of retinopathy, avoid the straining and breath-holding that is so often done during weightlifting or other forms of resistance exercise. Vigorous aerobic exercise may also pose a risk. By all means, check with your ophthalmologist first. You don’t want to experiment with your eyes.

DIABETIC FEET AND PERIPHERAL NEUROPATHY

Diabetics are prone to foot ulcers, infections, and ingrown toenails, especially if peripheral neuropathy (numbness or loss of sensation) is present. Proper foot care, including frequent inspection, is more important than usual if a diabetic exercises with her feet. Daily inspection should include the soles and in-between the toes, looking for blisters, redness, calluses, cracks, scrapes, or breaks in the skin. See your physician or podiatrist for any abnormalities. Proper footwear is important (for example, don’t crowd your toes). Dry feet should be treated with a moisturizer regularly. In cases of severe peripheral neuropathy, non-weight-bearing exercise (e.g., swimming or cycling) may be preferable. Discuss with your physician or podiatrist.

HYPOGLYCEMIA

Low blood sugars are a risk during exercise if you take diabetic medications in the following classes: insulins, sulfonylureas, meglitinides, and possibly thiazolidinediones and bromocriptine.

Hypoglycemia is very uncommon with thiazolidinediones. Bromocriptine is so new (for diabetes) that we have little experience with it; hypoglycemia is probably rare or non-existent. Diabetics treated with diet alone or other medications rarely have trouble with hypoglycemia during exercise.

Always check your blood sugar before an exercise session if you are at risk for hypoglycemia. Always have glucose tablets, such as Dextrotabs, available if you are at risk for hypoglycemia. Hold off on your exercise if your blood sugar is over 200 mg/dl (11.1 mmol/l) and you don’t feel well, because exercise has the potential to raise blood sugar even further early in the course of an exercise session.

As an exercise session continues, active muscles may soak up bloodstream glucose as an energy source, leaving less circulating glucose available for other tissues such as your brain. Vigorous exercise can reduce blood sugar levels below 60 mg/dl (3.33 mmol/l), although it’s rarely a problem in non-diabetics.

The degree of glucose removal from the bloodstream by exercising muscles depends on how much muscle is working, and how hard. Vigorous exercise by several large muscles will remove more glucose. Compare a long rowing race to a slow stroll around in the neighborhood. The rower is strenuously using large muscles in the legs, arms, and back. The rower will pull much more glucose out of circulation. Of course, other metabolic processes are working to put more glucose into circulation as exercising muscles remove it. Carbohydrate consumption and diabetic medications are going to affect this balance one way or the other.

If you are at risk for hypoglycemia, check your blood sugar before your exercise session. If under 90 mg/dl (5.0 mmol/l), eat a meal or chew some glucose tablets to prevent exercise-induced hypoglycemia. Re-test your blood sugar 30–60 minutes later, before you exercise, to be sure it’s over 90 mg/dl (5.0 mmol/l). The peak effect of the glucose tablets will be 30–60 minutes later. If the exercise session is long or strenuous, you may need to chew glucose tablets every 15–30 minutes. If you don’t have glucose tablets, keep a carbohydrate source with you or nearby in case you develop hypoglycemia during exercise.

Re-check your blood sugar 30–60 minutes after exercise since it may tend to go too low.

If you are at risk of hypoglycemia and performing moderately vigorous or strenuous exercise, you may need to check your blood sugar every 15–30 minutes during exercise sessions until you have established a predictable pattern. Reduce the frequency once you’re convinced that hypoglycemia won’t occur. Return to frequent blood sugar checks when your diet or exercise routine changes.

These general guidelines don’t apply across the board to each and every diabetic. Our metabolisms are all different. The best way to see what effect diet and exercise will have on your glucose levels is to monitor them with your home glucose measuring device, especially if you are new to exercise or you work out vigorously. You can pause during your exercise routine and check a glucose level, particularly if you don’t feel well. Carbohydrate or calorie restriction combined with a moderately strenuous or vigorous exercise program may necessitate a 50 percent or more reduction in your insulin, sulfonylurea, or meglitinide. Or the dosage may need to be reduced only on days of heavy workouts. Again, enlist the help of your personal physician, dietitian, diabetes nurse educator, and home glucose monitor.

Finally, insulin users should be aware that insulin injected over muscles that are about to be exercised may get faster absorption into the bloodstream. Blood sugar may then fall rapidly and too low. For example, injecting into the thigh and then going for a run may cause a more pronounced insulin effect compared to injection into the abdomen or arm.

medical clearance, treadmill stress test

This treadmill stress test is looking for hidden heart disease

AUTONOMIC NEUROPATHY

This issue is pretty technical and pertains to function of automatic, unconscious body functions controlled by nerves. These reflexes can be abnormal, particularly in someone who’s had diabetes for many years, and are called autonomic neuropathy. Take your heart rate, for example. It’s there all the time, you don’t have to think about it. If you run to catch a bus or climb two flights of stairs, your heart rate increases automatically to supply more blood to exercising muscles. If that automatic reflex doesn’t work properly, exercise is more dangerous, possibly leading to passing out, dizziness, and poor exercise tolerance. Other automatic nerve systems control our body temperature regulation (exercise may overheat you), stomach emptying (your blood sugar may go too low), and blood pressure (it could drop too low). Only your doctor can tell for sure if you have autonomic neuropathy.

Steve Parker, M.D.