Factors that can impact your HbA1c if you have type 2 diabetes

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The HbA1c test is a blood test that can be used to monitor how well your type 2 diabetes treatment plan is working. The test measures your average blood sugar levels over the past 3 months.

HbA1c tests results are given as a percentage or number. The higher the percentage or number, the higher your blood sugar levels have been over that time.

According to Diabetes UK, “If you're at risk of developing type 2 diabetes, your target HbA1c level should be below 42mmol/mol (6%).” This goal may differ from person to person, though, depending on age and any additional medical conditions. You should speak with your doctor about the goal that’s right for you.

If you’ve been following your type 2 diabetes management and treatment plan but you’re not hitting your HbA1c goal, it doesn’t mean you’ve failed or done anything wrong. Many factors can impact your HbA1c results. Some are out of your control, and others you can take steps to manage. 

Here are 10 reasons your HbA1c may not be at goal.

1. Type 2 diabetes progression

Over time, you may notice that it becomes harder to hit your blood sugar targets, even if you’re still following the same diet, exercise, and treatment plans. That’s because type 2 diabetes is a progressive condition.

The cells in your body may stop responding to insulin produced by your pancreas. And eventually, your pancreas may produce less insulin or stop producing insulin altogether. As type 2 diabetes progresses, your treatment plan may no longer work as well as it used to. You may need to work with your GP to adjust your medication in order to hit your HbA1c goal.

Studies estimate that HbA1c levels will increase roughly 1% every 2 years, even with most diabetes treatments. You can still take steps to manage your blood sugar by working with your GP, making lifestyle changes, and if prescribed, taking your type 2 diabetes medication.

2. Hormonal changes

A number of hormonal changes can affect your HbA1c level. Menstruation and menopause create hormonal changes in your body, which can then affect blood sugar levels for women. Physical or emotional stress can also play a role in your HbA1c level. Stress triggers the release of hormones that can raise your blood sugar level, which can cause your HbA1c to increase as well.

If you’re experiencing hormonal changes, you can talk with your GP about adjusting your treatment plan, if needed. You can also ask your doctor about ways to manage stress. Stress-relieving activities may include:

·       exercising or breathing techniques (eg Box Breathing or Wim Hof technique)

·       practicing other relaxation techniques such as mindful meditation or yoga

·       spending time with family and friends, or with like minded people

·       doing a hobby, you enjoy

3. Pregnancy

Some research shows that HbA1c results can be falsely low in pregnant women, especially those in the second or third trimester. Pregnancy alters the lifespan of red blood cells, which can affect HbA1c results. You may have different blood sugar and HbA1c targets during your pregnancy. Talk with your GP about the goals that are right for you and whether you need to adjust your treatment plan to meet those goals.

4. Diabetes-related complications or comorbidities

Certain diabetes-related complications can make it harder to manage blood sugar, which can impact your HbA1c result. For example, gum disease, a common complication of diabetes, can raise your blood sugar levels.

Chronic kidney disease (CKD) is another condition common in people with diabetes. Research shows that HbA1c may not be a reliable measure of blood sugars levels in people with diabetes and CKD. Kidney failure and complications of CKD, such as anaemia, may cause falsely high HbA1c results.

Seeing a doctor regularly can help you prevent or manage diabetes complications and related health conditions. Other potential complications include:

·       heart disease

·       nerve damage

·       eye or vision problems

·       foot problems

5. Medications for other conditions

Certain medications, such as opioids and some HIV medications, may cause falsely high HbA1c results. Talk with your GP about any medications or supplements you take and how they may impact your HbA1c.

6. Blood loss or blood transfusions

The lifespan of red blood cells is one of the biggest influences on HbA1c levels. That’s because the HbA1c test measures the percentage of your red blood cells that have glucose attached to the haemoglobin, a protein in red blood cells. Changes in red blood cells can change your HbA1c. If you’ve recently experienced blood loss or had a blood transfusion, your HbA1c results may be inaccurate. 

7. Untreated anaemia

People with very low iron levels might experience a falsely high HbA1c result. This is especially true for individuals with iron-deficiency anaemia, a common type of anaemia caused by a lack of iron. Iron is needed to make new red blood cells to replace older red blood cells. If you have unusually high HbA1c levels and suspect anaemia may be the cause, it’s a good idea to talk with your doctor and do further testing if needed.

8. Treatment that’s no longer effective

Type 2 diabetes can progress or change, which means sometimes a different treatment approach might be necessary to manage your HbA1c level. If your treatment is no longer effective and is impacting your blood sugar levels, talk with your doctor about making an adjustment. You may need to:

·       start taking medication if you’re currently managing with diet and exercise

·       change the dosage of your current medication

·       switch to a new medication

·       switch from oral diabetes medications to insulin

9. Natural fluctuations in blood sugar

Your blood sugar naturally fluctuates throughout the day. Many things can impact your blood sugar, such as:

·       the amount of carbohydrates you eat

·       your physical activity level 

·       quality of sleep

·       stress

Fluctuating blood sugar can affect your HbA1c readings, which is the average of your blood sugar over a few months. Testing your blood sugar regularly can help you see how certain factors affect your blood sugar and help you stay in your target range.

10. External factors 

Sometimes, a HbA1c test can be affected by external factors outside of your control. Surprising influences like temperature, equipment used, and even how samples are handled in the lab can cause falsely high or low HbA1c results. If you suspect a false result due to external sources, ask your doctor to repeat your A1C test.

Takeaway

It’s important to manage type 2 diabetes to help prevent the disease from progressing. Sometimes, even those who follow their diet, exercise, and treatment plans may experience higher or lower HbA1c levels. This doesn’t mean you’re doing something wrong. Instead, it could be indicative of changes to your condition or other factors impacting blood sugar levels, such as pregnancy or medication.

If your HbA1c isn’t at goal, consult with your GP to identify possible factors and discuss changes to treatment, if necessary, to help get your blood sugar levels to numbers that are right for you.

Extracts taken from Kelly Wood, MD from https://www.healthline.com