Diabetes: Tests You Need and Why

Diabetes is a condition that can affect your whole body. When your blood glucose (sugar) stays too high for too long, it can lead to problems with your heart, blood vessels, eyes, nerves, and kidneys. By getting regular tests and checkups, you can help control your glucose level and prevent or delay damage caused by high blood glucose. Watching your health closely lets you react to problems early before they get more serious.

Here’s a list of several diabetes-related tests and checkups, as well as guidelines for how often each is needed. Keep in mind that you may need more frequent testing or checkups if you have signs of problems. Your doctor can suggest the best schedule for you.

A1C test

This blood test shows the average amount of glucose in your blood during the past 3 months. The results show how well your blood glucose is controlled and if your treatment plan needs any changes. The A1C target level for many people is less than 7%. But this target level may vary depending on your age, how long you have had diabetes, and other risk factors.

How often: Have this test at least 2 times a year if you are at your goal with stable blood glucose. Have this test more often if your therapy has changed or you're not meeting stable blood glucose goals. Your doctor may suggest a few weeks of continuous glucose monitoring to possibly find dangerous trends that even multiple blood sticks per day may not find. Examples are periods of dangerously low blood sugars from too high doses of some medicines.

Blood lipids test

This blood test checks for several types of fat in your blood. LDL (bad) cholesterol can narrow or block blood vessels. This can possibly lead to a heart attack or stroke. Those with diabetes are at a higher risk for these types of problems. Most people with diabetes will be advised to eat a low-fat, heart-healthy diet and take a cholesterol-lowering medicine to improve outcomes. Your total cholesterol should be lower than 200 mg/dL. And your LDL level should be lower than 100 mg/dL. If you have both diabetes and cardiovascular disease, your LDL level should be lower than 70 mg/dL. Triglycerides are another type of harmful fat that raise your risk for heart attack and stroke. Aim for a fasting triglyceride level lower than 150 mg/dL. HDL (“good”) cholesterol helps keep your blood vessels healthy. Your HDL level should be higher than 40 mg/dL for men or higher than 50 mg/dL for women.

How often: Have this test at least once a year.

Blood pressure test

Controlling your blood pressure helps prevent heart, blood vessel, eye, and kidney problems. The target for adults with diabetes is a blood pressure reading lower than 130/80 mm Hg. Both numbers matter. The first is the pressure as your heart beats and pushes blood into your blood vessels. The second is the pressure as your heart rests between beats.

How often: Your blood pressure is checked at every doctor visit. You can check your own blood pressure at home and keep a record of it to show to your doctor at your appointment.

Dental checkup

Having diabetes puts you at higher risk for tooth and gum problems. So it’s very important to have your teeth cleaned and checked at your dentist’s office on a regular basis. At each dental visit, give your dentist a list of your current medicines and how much you take of each.

How often: Have a dental checkup at least twice a year.

Dilated eye exam

High blood glucose and high blood pressure can harm the eyes. In a dilated eye exam, an eye doctor puts drops in your eyes to briefly enlarge your pupils. This makes it easier for the doctor to look inside your eyes for signs of damage. Often photos are taken to document any eye damage and to compare findings from previous exams.

How often: Have a dilated eye exam once a year by a licensed ophthalmologist or optometrist.

Foot exam

Nerve damage, poor blood flow, and infections due to diabetes can cause foot problems. Nerve damage can lead to a loss of feeling in the feet, putting you at risk for injuries and falls. Or it can cause ulcers to develop. Poor circulation can mean that sores or infections heal slowly. If these problems aren’t treated right away, they can lead to serious infection or amputation. At every doctor visit, have your feet checked for sores. In addition, you should check your feet every night for redness, injuries, or blisters. And you should have a full foot exam each year. Your doctor should check the integrity of your skin, the status of your toenails, and the feeling and circulation in your feet.

How often: Do daily self-exams of your feet, and have a comprehensive foot exam by your doctor once a year.

Kidney function tests

Diabetes can damage the kidneys and over time cause kidney failure. Various tests can help find kidney problems before they become severe. Albumin-to-creatinine ratio test checks for a protein called microalbumin in the urine, an early sign of kidney disease. Estimated glomerular filtration rate checks for creatinine in the blood, a waste product that builds up when the kidneys aren’t working correctly.

How often: Have a kidney function test one or more times a year, depending on the type of diabetes you have and how the kidney disease is progressing.

Bone mineral density scan

People with diabetes are at an increased risk for fractures and osteopenia or osteoporosis (bone loss). If you have additional risk factors, such as having previous fractures or having gone through menopause, talk to your doctor about a bone mineral density scan. A bone mineral density scan helps estimate the density of your bones and how likely they are to break.

How often: A baseline scan is usually recommended for women when they start menopause and for men at around age 50 if they have a history of adult-age fracture or diabetes-specific risk factors. Ask your doctor how often you should have a bone mineral density scan.

Peripheral artery disease (PAD) screening

People with diabetes are at an increased risk for PAD. PAD is a condition in which clogged arteries reduce blood flow to your lower limbs. PAD can cause leg pain, weakness and numbness, especially when walking. It can also make it harder for foot sores to heal. An ankle-brachial index (ABI) test measures blood pressure at the ankle. Results are compared to a blood pressure reading at the arm. ABI is recommended for people with PAD symptoms, people without PAD symptoms at age 50 and above, any microvascular disease, or diabetes-related end-organ damage or foot complications. PAD screening is also considered for people who have had diabetes for 10 or more years.

How often: Ask your doctor how often you should have PAD screening.

Early heart failure screening

People with diabetes have an increased risk for structural heart failure. Heart failure screening is recommended to find early heart failure, even for people without heart failure symptoms. This is done with a blood test called B-type natriuretic peptide (BNP) or N-terminal pro BNP (NT-proBNP). Higher-than-normal levels can mean that your heart is not working as it should and may not be pumping enough blood through your body.

How often: Have early heart failure screening at least once a year.