In This Chapter

Understanding why monitoring is a must

Checking glucose with meters and A1c

Testing for kidney damage

Examining your eyes and feet

Finding your level of cholesterol and other fats

Gauging your blood pressure, weight, and other details

You may wonder what you have to do to prevent the complications of diabetes that I describe in Chapters 4 through 6, and the answer is a fair amount, which I discuss in this chapter. But when you weigh the benefits that add up to a longer, better-quality life against the loss of time and money from preventive care, the benefits of preventive care win by a landslide.

With preventive care, you can take advantage of an explosion of new tests and treatments that have only been available for the last 35 years, beginning with self-testing of blood glucose in 1980 right up to new tests for overall diabetic control and multiple new hardware and software tools made possible by the latest advances in computer and Internet technology.

As Woody Allen points out, “I don’t want to achieve immortality through my work; I want to achieve it through not dying.” On the other hand, he says, “On the plus side, death is one of the few things that can be done just as easily lying down.” Well, I don’t want you to take your diabetes lying down. I want to give you the benefit of every important advance. You may not achieve immortality, but you can enjoy every day that you live.

This chapter gives you all the tools you need to detect complications in their earliest stages. And if, by chance, you are reading this section for the first time and complications have already developed, this chapter also shows you how to measure the progression or, hopefully, regression of your complications.

Testing, Testing: Tests You Need to Stay Healthy

A number of tests and measurements should be done on a regular basis. To best make sure that you get your tests done regularly, you can use the chart in Figure 7-1. This form lists the tests and you can list the results underneath. Simply copy the one in this figure and keep it up-to-date. Don’t expect your doctor to keep this chart updated for you. He has too much on his mind and too many patients to get it exactly right for each one.

Certain procedures, explained in this chapter, should be done by your doctor (and you, if feasible) according to the following schedule:

• Blood glucose: At each visit, evaluate the blood glucose measurements you’ve been taking. (See the section “Monitoring Blood Glucose: It’s a Must,” later in this chapter.)
• Hemoglobin A1c: Obtain hemoglobin A1c four times a year if you take insulin and twice a year if you don’t. (See the section “Tracking Your Glucose over Time: Hemoglobin A1c,” later in this chapter.)
• Eye exam: Have a dilated eye examination by an ophthalmologist or optometrist once a year or every two years if no disease is present. (See the section “Checking for Eye Problems,” later in this chapter.)

• Filament: Examine your bare feet at each visit and have your doctor perform a filament test. (See the section “Examining Your Feet,” later in this chapter.)

  In addition to looking at the feet, you should also have an ankle-brachial index performed at least every five years.

• TSH: Your doctor should check your thyroid-stimulating hormone level when your diabetes is diagnosed and every five years thereafter if it is normal.
• Ualb: Check for microalbuminuria once a year. (See the section “Testing for Kidney Damage: Moderately Increased Albumin (MIA),” later in this chapter.)
• Chol/LDL/HDL/TG: Obtain a lipid panel once a year to monitor your total cholesterol, LDL (bad cholesterol), HDL (good cholesterol), and triglycerides. (See the section “Tracking Cholesterol and Other Fats,” later in this chapter.)

In addition to the preceding tests, you should also have your doctor take your blood pressure and measure your weight at each visit. (See the sections “Measuring Blood Pressure” and “Checking Your Weight and BMI,” later in this chapter.)

These tests are the minimum standards for proper care of diabetes. If an abnormality is found, the frequency of testing increases to check on the response to treatment.

Are doctors and patients with diabetes doing the best job of managing diabetes? Government statistics on Preventive Care Practices from the Centers for Disease Control and Prevention (CDC) suggest that they aren’t. Doctors and patients are getting a little better as diabetes becomes a major health problem in the United States. The latest statistics compare the annual rates of testing for various abnormalities associated with diabetes between 1994 and 2010. They indicate some improvement, but as a whole they should be doing a lot better. Only about 60 percent of diabetic patients are doing frequent testing of blood glucose, A1C tests at least twice a year, annual eye exams, and annual foot exams.

As diabetes knowledge has grown, the guidelines for how high various tests should be in people with diabetes have changed. Unfortunately, they seem to have no effect on the results of clinical practice:

• The Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure lowered its guidelines for blood pressure in people with diabetes in 1997 and again in 2003, but as of 2008 there was no better control, according to the CDC.
• The American Diabetes Association lowered its goal for LDL cholesterol (see later in this chapter) to less than 100 mg/dl in 1998. As late as 2010, there was no indication that patients were meeting the new goal more often than they had in 1994.

Much can be done. And that’s what this chapter is all about.

Monitoring Blood Glucose: It’s a Must

Insulin was extracted and used for the first time more than 90 years ago. Since that time, nothing has improved the life of the person with diabetes as much as the ability to measure his or her own blood glucose with a drop of blood.

Prior to blood glucose self-monitoring, testing the urine for glucose was the only way to determine whether your blood glucose was high, but urine testing could not tell at all whether the glucose was low. The urine test for glucose is worthless for controlling blood glucose — it actually provides misinformation. All the thousands of research papers in the medical literature before 1980, which used urine testing for glucose, are of no value and should be burned. (However, testing urine for other things, such as ketones and protein, can be of value.)

Basically, two kinds of test strips are used today. Both require that glucose in a drop of your blood reacts with an enzyme. In one strip, the reaction produces a color. A meter then reads the amount of color to give a glucose reading. In the other strip, the reaction produces electrons, and a meter converts the amount of electrons into a glucose reading.

One of the first things that was learned when frequent testing of blood glucose became feasible is that a person with diabetes, even a person who works hard to control his glucose, can experience tremendous variation in glucose levels in a relatively short time, as little as 30 minutes. This variation is especially true in association with food, but it can occur even in the fasting state before breakfast. For this reason, multiple tests are needed.

Choosing a Blood Glucose Meter

The meter business must be a profitable one because many new meters are on the market each time I update this book. But the cost of the meter should play little part in your decision about which one to get. Most manufacturers are happy to practically give you the meter so that you’re forced to buy their test strips. Each manufacturer makes a different test strip, and they’re not interchangeable in other machines. Some companies even make a different strip for each different machine that they make.

Because the meters are so cheap and the science is changing so rapidly, you should get a new meter every year or two to make sure that you have state-of-the-art equipment. The cost of test strips is generally about the same from meter to meter, so the cost of strips does not have to play a big role in your meter decision, either.

The accuracy of the various machines also isn’t a consideration. All are accurate to a degree acceptable for managing your diabetes. Keep in mind, though, that they do not have the accuracy of a laboratory. Meters are probably about plus or minus 10 percent compared to the lab.

Tracking Your Glucose over Time: Hemoglobin A1c

In order to follow your improvement with treatment, you need a test that gives you the big picture, the average blood glucose over time. As I explain in Chapter 2, the hemoglobin A1c is that test. Figure 7-2 shows you the correlation between the hemoglobin A1c and the estimated average blood glucose. By correlating the A1c with the estimated average blood glucose, you can think of the A1c in the same units as the blood glucose that you measure several times a day.

As you can see in the figure, a normal hemoglobin A1c of less than 6 percent corresponds to an estimated average blood glucose of less than 126, while a fair hemoglobin A1c of 7 percent reflects an average blood glucose of 155.

Large-scale studies have shown that the average hemoglobin A1c in the United States for type 2 diabetes is around 9.4 percent, which means the average blood glucose is 223. The American Diabetes Association recommends taking action to control the blood glucose if the hemoglobin A1c is 8 percent or greater, with the goal being less than 7 percent.

The American Association of Clinical Endocrinologists suggests a goal of 6.5 percent or less. Although I wish all of my patients would achieve a level of 6.5 percent, I try to get them as low as possible but still consistent with a decent quality of life, which means few to no severe hypoglycemic episodes.

Your physician should test for hemoglobin A1c as follows:

• Four times a year if you have type 1 or type 2 diabetes and are on insulin
• Two times a year if you have type 2 diabetes and are not on insulin

In my own practice, I test all patients every three months. A good hemoglobin A1c is highly motivating to keep up good self-care, whereas a poor result gives immediate feedback as to the need for tighter control.

The National Glycohemoglobin Standardization Program, created by the American Association for Clinical Chemistry, has standardized the hemoglobin A1c test so that a 6 percent result means the same thing for every patient.

A study published in Diabetes Care in January 2011 showed that the hemoglobin A1c changes much more frequently in gestational diabetes. The authors recommend weekly testing of the A1c to guide treatment. If you have gestational diabetes, discuss this issue with your doctor.

Bayer sells a clever home version of the hemoglobin A1c called A1c Now. You do a finger stick to produce a large drop of blood. The blood is mixed with a solution that is provided, and a sample of that mixture is placed in the testing device. Five minutes later, the hemoglobin A1c result appears in the device window. The device is then discarded. The device appears to be highly accurate and may save the trouble of going to a lab for this test. Because it’s so quick, your doctor can have the test results while you’re at his office and can act on them immediately, instead of waiting for a lab to return the test results at a later time. The test kit is available at pharmacies without a prescription, for about $30 a test. It is annually certified by the National Glycohemoglobin Standardization Program.

Another option is to collect your own blood specimen and send it to a company that runs the test and gives you and your doctor a result. Following are some companies currently doing this test:

• AccuBase A1c Glycohemoglobin: Each test costs $29.59 and includes lab analysis and reporting. It can be ordered on the Internet at Amazon.com or American Diabetes Wholesale.
  • Phone: 888-872-2443
  • Website: http://dtilaboratories.com/diagprod.htm
• Walgreen’s A1c at Home: This testing service costs $39.99 each including lab analysis and reporting.
  • Phone: 800-925-4733
  • Website: www.walgreens.com/store/c/walgreens-at-home-a1c-test-kit/ID=prod6248361-product

The Diabetes Control and Complications Trials have shown that maintaining a hemoglobin A1c of 7 percent or less for several years early in type 1 diabetes results in diabetes complications 50 percent or lower 20 years later, even when the A1c is higher after those years.

Low thyroid function falsely raises the hemoglobin A1c. An A1c between 5.7 and 6.4 percent is an indicator of prediabetes.

Testing for Kidney Damage: Moderately Increased Albumin (MIA)

The finding of very small but abnormal amounts of protein in the urine, called moderately increased albumin (MIA) (formerly microalbuminuria), is the earliest sign that high glucose may be damaging your kidneys (see Chapter 5). When MIA is found, you still have time to reverse any damage.

As soon as you are diagnosed with type 2 diabetes, and within five years of being diagnosed with type 1, your doctor must order a urine test for MIA. If the test is negative, it must be repeated annually. If the test is positive, it should be done a second time to verify the result. If the second test is positive, your doctor should do the following:

• Put you on a drug called an ACE inhibitor: After you have been on this drug for some months, the test for MIA can be repeated to see whether it has turned negative. The ACE inhibitor can be stopped and restarted later if MIA appears again. If ACE inhibitors aren’t tolerated, then ARBs, another class of antihypertensives, may be used. Both classes have been shown to reverse MIA and the ongoing kidney damage it reflects.
• Bring your blood glucose under the tightest control possible. Bringing it under control helps to reverse the damaging process as well.
• Normalize your body fats so that your cholesterol and triglycerides are made normal. Elevated cholesterol and triglycerides have been found to damage the kidneys. (See the section “Tracking Cholesterol and Other Fats,” later in this chapter.)
• Bring your blood pressure under control. Lowering your blood pressure will help to minimize the damage to your kidneys that occurs when they are exposed to elevated blood pressure.

Doing this simple little test can protect your kidneys from damage. Ask your doctor about it if you think you’ve never had it done. Show him or her this page if the doctor is unclear as to why it is performed.

Up to 25 percent of patients with diabetes can have ongoing kidney damage without showing an elevated microalbumin. For this reason, the idea that all patients with diabetes should receive an ACE inhibitor may not be far-fetched.

Women who have gestational diabetes and show MIA have been found to have heart disease and kidney disease later, even if they don’t develop diabetes. Persistent MIA predicts later heart disease even in the absence of gestational diabetes.

Checking for Eye Problems

All people with diabetes need to have a dilated eye exam done annually (or every two years if no eye disease is present) by an ophthalmologist or optometrist. No other physician, including the endocrinologist (yours truly excepted, of course), can do the exam properly.

For this exam, the doctor instills drops into your eyes and uses various instruments to examine the pressure, the appearance of your lens, and, most importantly, the retina of your eye.

All kinds of treatments can be done if abnormalities are found, but they must be discovered first. (See Chapter 5 for more information on eye problems.)

This test is something you must demand. Your doctor must refer you to an ophthalmologist or optometrist every year. Better yet, set up the appointment yourself with the eye doctor’s nurse at the end of your first visit so that you are reminded about it each year. People who have mild type 2 diabetes and no retinopathy may be tested at two-year intervals rather than annually.

Examining Your Feet

Failing to take care of your feet leads to problems that often end in amputation. An amputation is really evidence of inadequate care. (For more on foot problems, see Chapter 5.) The doctor is not necessarily at fault here. The doctor sees you once in a while; you’re with yourself much more often.

If you have any problem sensing touch with your feet, you need to take the following precautions:

• You must use your eyes to examine your feet every day.
• You must use your hand to test hot water before you step into it so that you do not get burned.
• You must shake out your shoes before you step into them to make sure no stone or other object is inside them.
• You must not go barefoot.
• You must keep the skin of your feet moist by soaking them in water, drying them with a towel, and applying a moisturizing lotion. (Soaking should always be accompanied by drying and moisturizing.)

Your doctor can test your ability to feel an injury by using a 10-gram filament, but, again, that is done only when you have an appointment. You can obtain one of these filaments for yourself. A couple of the places where you can get them include

• Lower Extremity Amputation Prevention (LEAP) Program: www.hrsa.gov/hansensdisease/leap
• Medical Monofilament Manufacturing, LLC: www.medicalmonofilament.com, or call 508-746-7877

If you have any suggestion of a loss of sensation, at each visit to the doctor who takes care of your diabetes, you should take off your shoes and socks and have your feet inspected.

The other part of a foot examination involves checking the circulation of blood to your feet. To check the circulation, your doctor does a measurement called an ankle-brachial index at least once every five years. The systolic blood pressure is measured in the ankle and the arm. (See the sidebar “The meaning of your blood pressure,” later in this chapter, for an explanation of systolic blood pressure.) The value for the ankle is divided by the value for the arm. An index of greater than 0.9 is considered normal. A value between 0.4 and 0.9 indicates peripheral vascular disease (see Chapter 5), and a value less than 0.4 indicates severe disease.

The ankle-brachial index should be done for any person with diabetes over age 50. Patients under 50 require the study if risk factors such as smoking, high cholesterol, and high blood pressure are present.

Tracking Cholesterol and Other Fats

Most people these days know the level of their total cholesterol, but other tests that show levels of various types of fats in the blood are needed as well.

Cholesterol is a type of fat that circulates in the blood in small packages called lipoproteins. These tiny round particles contain fat (lipo, as in liposuction) and protein. Because cholesterol does not dissolve in water, it would separate from the blood if it were not surrounded by the protein, just like oil separates from water in salad dressing. (That’s why you have to shake the salad dressing each time you use it.)

A second kind of fat found in the lipoproteins is triglyceride. Triglyceride actually represents the form of most of the fat you eat each day. Although you may eat only a gram or less of cholesterol (an egg yolk has one-third of a gram of cholesterol), you eat up to 100 grams of triglyceride a day. (For more on the place of fats in your diet, see Chapter 8.) The fat in animal meats is mostly triglycerides.

Four types of lipoproteins exist:

• Chylomicrons: The largest of the fat particles, these lipoproteins contain the fat that is absorbed from the intestine after a meal. They are usually cleared from the blood rapidly. Ordinarily, chylomicrons are not a concern with respect to causing arteriosclerosis (hardening of the arteries).
• Very-low-density lipoprotein (VLDL): These particles contain mostly triglyceride as the fat. They’re smaller than chylomicrons.
• High-density lipoprotein (HDL): Known as “good” cholesterol, this lipoprotein is the next smallest in size. This particle functions to clean the arteries, helping to prevent coronary artery disease, peripheral vascular disease, and strokes.
• Low-density lipoprotein (LDL): Known as “bad” cholesterol, this smallest particle is the particle that seems to carry cholesterol to the arteries, where it’s deposited and causes hardening.

As you may imagine, doctors need to know which particle your cholesterol comes from in order to understand whether you have too much bad cholesterol (LDL) or a satisfactory level of good cholesterol (HDL).

You don’t have to fast to test for total cholesterol and HDL cholesterol. However, you do need to fast for eight hours to find out your LDL cholesterol and triglycerides, because the blood has to be cleared of chylomicrons, which rise greatly when you eat.

You should have a fasting lipid panel at least each year or two. A fasting lipid panel gives you your total cholesterol, your LDL cholesterol, your HDL cholesterol, and your triglyceride levels. If your values indicate you are at low risk (LDL less than 100, HDL greater than 50), the fasting lipid panel may be done every two years.

Table 7-1 lists the current recommendations for the levels of these fats in terms of the risk for coronary artery disease.

You can see in Table 7-1 that the risk goes up as the LDL cholesterol goes up and the HDL cholesterol goes down. A huge study of thousands of citizens of Framingham, Massachusetts, shows that you can get a good picture of the risk by dividing the total cholesterol by the HDL cholesterol. If this result is less than 4.5, the risk is lower. If it’s greater than 4.5, you’re at higher risk for coronary artery disease. The higher it is, the worse the risk.

In March 2004, the story got a little more complicated. The New England Journal of Medicine published results of a study of more than 4,000 men who had just had heart attacks. In the study, some patients’ LDL cholesterol was reduced maximally (to a mean of 62) with a large dose of a powerful drug called atorvastatin. The result was a major reduction, starting in just 30 days after treatment with the drug, in subsequent heart attacks, chest pain, and strokes compared to a group whose LDL was lowered only to 95. This result calls for a major reappraisal of what LDL is considered normal. Experts agree that the lowest possible LDL level is best and that this policy applies to everyone, not only people who have just had a heart attack.

Diabetes adds its own complication because of metabolic syndrome (see Chapter 5). In metabolic syndrome, the total cholesterol may not be very high, but the HDL cholesterol is low and the triglycerides are elevated. These patients also have a lot of a dangerous form of LDL cholesterol, so they are at higher risk for coronary artery disease. This increased risk must be taken into account in considering treatment for the fats.

In deciding whether and how to treat the fats, you have to consider other risk factors for coronary artery disease. You’re at high risk if you have diabetes and fit any of the following conditions:

• You already have coronary artery disease, stroke, or peripheral vascular disease.
• You are a male over 45.
• You are a female over 55.
• You smoke cigarettes.
• You have high blood pressure.
• You have HDL cholesterol less than 35.
• You have a father or brother who had a heart attack before age 55.
• You have a mother or sister who had a heart attack before age 65.
• You have a body-mass index greater than 30.

You’re at low risk if you have none of the preceding risk factors.

The treatment for abnormal fats with statins (see Chapter 11) then depends on your age and the presence of these cardiovascular disease (CVD) risk factors (see Table 7-2).

All these decisions depend on obtaining a lipid (fat) panel as needed to monitor adherence.

These treatment guidelines will change as the experts have a chance to evaluate the LDL study of heart-attack victims that I discuss in this section.

After LDL cholesterol is lowered, even below 70, a higher level of HDL cholesterol has been found to be associated with fewer heart attacks than a lower level.

Measuring Blood Pressure

The United States is experiencing an epidemic of high blood pressure (hypertension) similar to the epidemic of diabetes. The reasons are the same:

• Americans are getting fatter.
• Americans are storing fat in the center of our bodies, the so-called abdominal visceral fat.
• Americans are getting older as a population. The fastest-growing segment of the population is over 75 years of age. Of people age 50 to 55 with diabetes, 50 percent have high blood pressure. Of people older than 75 with diabetes, 75 percent have high blood pressure.
• Americans are more sedentary than before.

People with diabetes have high blood pressure more often than the nondiabetic population for a lot of other reasons besides the preceding ones:

• People with diabetes get kidney disease.
• People with diabetes have increased sensitivity to salt, which raises blood pressure.
• People with diabetes lack the nighttime fall in blood pressure that normally occurs in people without diabetes.

Doctors generally agree that a normal blood pressure is less than 140/90. For years, the diastolic blood pressure (the lower reading) was considered more damaging, and an elevation in that pressure was treated with greater importance than an elevation in the systolic blood pressure (the higher reading). More recent studies have shown that the systolic blood pressure, not the diastolic blood pressure, may be more important. (See the sidebar “The meaning of your blood pressure” for more detailed explanations of each type of blood pressure.)

All the complications of diabetes are made worse by an elevation in blood pressure, especially diabetic kidney disease but also eye disease, heart disease, nerve disease, peripheral vascular disease, and cerebral arterial disease (see Chapter 5).

Evidence of the importance of controlling blood pressure in diabetes comes from the United Kingdom Prospective Diabetes Study, published in late 1998. This study found that a lowering of blood pressure by 10 mm systolic and 5 mm diastolic resulted in a 24 percent reduction in any diabetic complication and a 32 percent reduction in death related to diabetes.

Lowering the blood pressure to less than 120/80 is absolutely essential in diabetes. How well are doctors doing at controlling blood pressure in people with diabetes? A study in 2012 showed that only 29 percent of people with diabetes with hypertension have a blood pressure as low as 120/80.

Your doctor should measure blood pressure at every visit. Better yet, get a blood pressure device and measure it yourself. If you detect an elevation, bring it to the attention of your doctor.

Pregnant women with diabetes who have high blood pressure should not take ACE inhibitors or ARBs (two classes of drugs). They’re known to be harmful to the growing fetus. If you have high blood pressure and plan to become pregnant, discuss your blood pressure medication with your doctor before conceiving.

For much more information on every aspect of high blood pressure, see my book High Blood Pressure For Dummies (John Wiley & Sons, Inc.).

Checking Your Weight and BMI

To give you a general idea of how much you ought to weigh, you can use the following formula:

• If you’re a woman, give yourself 100 pounds for being 5 feet tall and add 5 pounds for each inch over 5 feet. For example, if you’re 5 feet 3 inches, your appropriate weight should be approximately 115 pounds.
• If you’re a man, give yourself 106 pounds for being 5 feet tall and add 6 pounds for each inch over 5 feet. A 5-foot 6-inch male should weigh around 142 pounds.

Body-mass index (BMI) is a measurement that relates weight to height. A tall person has a lower BMI than a short person of the same weight. (See Chapter 3 for more on BMI, including instructions for calculating your own BMI.) A person with a BMI under 18.5 is considered underweight. A person with a BMI from 18.5 to 24.9 is normal. A person with a BMI from 25 to 29.9 is overweight, and a person with a BMI of 30 or over is obese. By this definition, more than 69 percent of the people in the United States are overweight or obese as of 2012.

Non-white populations like South Asians, Chinese, and blacks develop diabetes at a lower BMI. Ethnicity must be considered in developing prevention techniques and targets for ideal body weight.

You can’t get a reading of your BMI by stepping on a scale, but you can get your weight. This measurement is one of the easiest in medicine. Your doctor should measure your weight at every visit.

The National Heart, Lung, and Blood Institute makes knowing your BMI easy. Using the calculator at www.cdc.gov/healthyweight/assessing/bmi/adult_BMI/english_bmi_calculator/bmi_calculator.html, just fill in your weight in pounds and your height in feet and inches, click “Compute BMI,” and get your result.

Maintaining a BMI in the normal range makes controlling your diabetes and blood pressure easier. Also, you must eliminate obesity as a risk factor for coronary artery disease.

Testing for Ketones

When your blood glucose rises above 250 mg/dl (13.9 mmol/L), or if you are pregnant with diabetes and your blood glucose is below 60 mg/dl (3.3 mmol/L), your doctor should probably check for ketones — products of the breakdown of fats. Finding ketones means that your body has turned to fat for energy. If you have high glucose and find ketones, you may need more insulin. If you have low glucose and find ketones during pregnancy, you may need more carbohydrates in your diet.

Testing for ketones is done by inserting a test strip into your urine and observing a purple color. The deeper the color, the greater the ketone level. If you find a large amount of ketones, you should contact your physician. Two sources for ketone test strips are Bayer Ketostix and Nipro Trueplus Ketone Test Strips.

Testing the C-Reactive Protein

C-reactive protein (CRP) is a substance in the blood that is produced by the liver when infection or inflammation is present. It can be measured with a simple blood test. Diabetes is associated with several features that suggest that inflammation plays an important role in the disease. People who develop diabetes have higher C-reactive protein than those who don’t. (Other substances associated with inflammation are also elevated in diabetes.)

Half the people with diabetes who have heart attacks have low or low-normal levels of LDL (bad) cholesterol. It is believed that inflammation plays a major role in many of these patients. Elevated CRP in the blood has been shown to directly contribute to blood-vessel damage and the formation of blood clots that cause heart attacks.

Drugs that improve diabetes lower the amount of C-reactive protein, which is also considered a marker for coronary artery disease.

Have your C-reactive protein measured with other blood tests about once a year. If the level is elevated, it may serve as a predictor of future diabetes or coronary artery disease. You need to work even harder to lower your blood glucose, improve your LDL and HDL cholesterol, and lower your blood pressure. About 90 percent of healthy individuals have CRP levels less than 3, and 99 percent have levels less than 10. This test isn’t essential in diabetes.

Checking the TSH

A screening test called the thyroid-stimulating hormone (TSH) level is done at the time that diabetes is diagnosed and every five years thereafter if it is normal. This test is done because people with diabetes (type 1) have a higher incidence of thyroid disease than the general population, because thyroid disease is often confused with other conditions, and because hypothyroidism can lead to weight gain, which obviously isn’t good for diabetes.

TSH is produced by the pituitary gland in the brain. When the thyroid gland makes the right amount of thyroid hormone, the pituitary produces the right amount of TSH to keep it working properly. The normal level in the blood is 0.5–2.5 microunits per milliliter (μU/ml).

When the thyroid makes inadequate amounts of thyroid hormone, the pituitary increases its production of TSH to stimulate the thyroid, and values of 10 or more μU/ml are not uncommon. When the thyroid makes too much thyroid hormone, it causes the pituitary to turn down its production of TSH, and values less than 0.5 μU/ml are found.

Too much thyroid hormone leads to insulin resistance, making diabetes worse than before. Too little thyroid hormone increases insulin sensitivity, so people with low thyroid function have reduced levels of blood glucose.

Low levels of thyroid hormone cause an elevation in the hemoglobin A1c in patients who don’t have diabetes as well as those who do. Replacing the thyroid hormone lowers the A1c to normal if diabetes is not present.

Much more about thyroid disease and its treatment can be found in my book Thyroid For Dummies (Wiley).

Evaluating Testosterone in Men with Type 2 Diabetes

About one third of men in the United States over the age of 65 have low levels of testosterone, and a similar percentage of those men have diabetes. Low testosterone is associated with changes in body composition that promote diabetes like increased fat and decreased muscle. According to tests done so far, giving testosterone to these men has not resulted in persistent improvement in glucose metabolism.

Older men who have significant reduction in muscle mass and increase in fat should have their testosterone measured. If very low, treatment with testosterone may be considered by you and your doctor. Such patients should at least make a major effort to increase exercise and decrease caloric intake, which often results in a rise in testosterone.

Checking Vitamin D

Recent studies suggest a relationship between low levels of vitamin D and the development of both type 1 and type 2 diabetes. Communities that live furthest from the equator, getting less sun to make vitamin D, have the highest incidence of type 1 diabetes. Vitamin D protects the body from autoimmunity (where the body attacks itself), and type 1 diabetes is an autoimmune disease. High levels of vitamin D are associated with a lower risk of developing type 2 diabetes. In a study, people who were prediabetic were given vitamin D over three months and showed a significant improvement in glucose metabolism and reduction in hemoglobin A1c. Severe vitamin D deficiency has been shown to predict death and heart attacks in both type 1 and type 2 diabetes.

A study in the Journal of Clinical Endocrinology and Metabolism in September 2010 showed that blood vitamin D levels were low in obese women. The greater the degree of obesity, the lower the vitamin D. When weight was lost, the vitamin D level rose and the insulin resistance declined.

Have your vitamin D level measured with a blood test if you have prediabetes or diabetes. Take supplemental vitamin D if the level is low.