Stress, Anxiety and Depression
Depression and Diabetes
The prevalence of major depression in the UK population at any one time is about 5%, although as many as one person in three may experience an episode of depression in their lifetime. The presence of other illnesses may complicate or worsen depression and vice versa.
Research has shown that depression may occur in:
- Up to 60% of stroke patients
- Up to 40% of people with Parkinson’s disease
- Up to 42% of cancer patients
- Up to 21% of people with irritable bowel syndrome
- Up to 14-18% of people with diabetes
A study by Brazilian researchers showed that among a group of people with diabetes, of those whose HbA1c levels averaged less than 9%, only 21% tested positive for depression. By comparison of those with HbA1cs over 9%, 42% tested positive for depression. Other research has shown that people with chronic conditions, including diabetes, are three times more likely to suffer depression than the general population.
The researchers used cognitive therapy to reverse the depression. In those people where depression improved, there was an average HbA1c of 8.3% while those who showed little improvement had an average of 11.3%. While these results show an association between high blood sugars and depression, it remains unclear whether high blood sugars cause the depression or depression causes high blood sugars. [American Diabetes Association Conference 1998]
Research published in 2010 found that:
- people with depression were 17% more likely to develop Type 2 diabetes
- people with diabetes were 29% more likely to have depression compared with people without diabetes
- the risk of diabetes was greater in those with depressed mood, rising to 25% greater in those on antidepressants
- People with diabetes had a greater risk of depression rising to 53% higher among those treated with insulin.
The researchers recommend lifestyle changes to lower the risk of both conditions eg weight management and regular exercise. [Arch Intern Med 2010;170:1884-9]
How do you know if you are depressed?
The signs of depression include the following:
- No longer enjoying or being interested in most activities.
- Feeling tired or lacking energy.
- Being agitated or lethargic.
- Feeling sad or low much of the time.
- Weight gain or weight loss.
- Sleeping too little or too much.
- Difficulty paying attention or making decisions.
- Thinking about death or suicide.
If you have some or all of these symptoms over two weeks or more, then you should see your doctor.
How does depression affect people with diabetes?
An international report has shown that having diabetes and depression has the greatest negative on quality of life compared to diabetes or depression alone, or other chronic conditions. [Lancet 2007;370:851-8]
Research using questionnaires has shown that depression in people with both Type 1 and Type 2 diabetes may have the following effects:
- They are less likely to eat the types and amounts of food recommended.
- Less likely to take all their medications.
- Less likely to function well, both physically and mentally.
- Greater absenteeism from work.
The need for diagnosis
Recent estimates suggest that up to three quarters of cases of depression in people with diabetes may go undiagnosed. This may be because of poor detection rates but it could also be that some people with diabetes don’t report their symptoms of depression because they see them as ‘just part of having diabetes’.
Screening for depression [not specifically for people with diabetes] has been recommended by national and international bodies and in the UK, the Department of Health recommends that all GPs use two simple questions to screen for symptoms of depression:
- During the last month, have you been bothered by feeling down, depressed or hopeless?
- During the last month, have you often been bothered by having little interest or pleasure in doing things?
If people answer ‘yes’ to either of these questions, they are given a questionnaire to answer to measure the extent and nature of the symptoms. So if you answer ‘yes’ to the two questions above or you have more mild symptoms, you are not alone and the clear message from research is to seek help from your doctor because there is a good chance that your life will improve.
It is important that similar methods are used in diabetes hospital clinics where many people with Type 1 diabetes receive their treatment.
Treatment for depression in people with diabetes has been shown to be effective and has the additional benefits of improving blood sugar control. The evidence suggests that cognitive behaviour therapy and anti-depressant medicines are as effective in people with diabetes as in those without diabetes. One study found that not only did treatment improve blood sugar control but during treatment there was an improvement in mood and weight. As the treatment of depression can improve blood sugar control, it is also likely to reduce the risk of complications but importantly, it can also improve quality of life.
It is also well recognised that exercise helps to reduce depression, so although it may be the last thing that people feel like doing, it is worth increasing the amount of exercise being taken.