For our readers: Our goal is to help increase awareness of the dual diagnosis of an eating disorder and type 1 diabetes (T1D), which is referred to as “ED-DMT1.” To accomplish this, we asked two experts, a physician and a registered dietitian who treat ED-DMT1, to answer questions about this condition. Please read the answers provided by these professionals, Ovidio Bermudez, M.D., and Jennifer Sommer, M.S., R.D. We thank them for contributing their expertise to Countdown.

What is ED-DMT1?  

The dual diagnosis of an eating disorder and type 1 diabetes is often referred to as “diabulimia,” however this is not a medically recognized term and it is not an accurate description. This syndrome is termed among healthcare professionals as “ED-DMT1,” which represents this dual diagnosis in an individual with type 1 diabetes. Note: “DMT1” refers to diabetes mellitus type 1. For clarity, “type 1 diabetes” will be spelled out in this article in place of the abbreviation “T1D.”

ED-DMT1 describes the intentional misuse of insulin for weight control. This could be caused by decreasing the prescribed dose of insulin, omitting insulin entirely, delaying the appropriate dose, or manipulating the insulin itself to render it inactive. Any of these actions can result in hyperglycemia (high blood glucose levels) and glucose excretion in the urine, which causes weight loss. So, in a sense, calories are “purged” this way, which is where the term diabulimia stems from. However, a person suffering from ED-DMT1 may not be diagnosed with bulimia or have any symptoms of bulimia such as binge eating and self-induced vomiting. On the other hand, some individuals may only withhold insulin after they have binged (whether it be a true binge or just a larger-than-typical amount of food) as a method of purging. People suffering from ED-DMT1 may exhibit any number of eating disorder behaviors—or they may only manipulate their insulin and otherwise have normal eating patterns.

How many people in the United States have ED-DMT1, and who is at highest risk? 

It is unclear exactly how many people in the United States have ED-DMT1. What is a striking statistic is the percentage of people who have type 1 diabetes who also have an eating disorder or disordered eating. “Eating disorder” refers to abnormal eating habits that may involve either insufficient or excessive food intake to the detriment of a person’s health, such as anorexia nervosa or bulimia nervosa. “Disordered eating” refers to a wide range of irregular eating behaviors that do not warrant a diagnosis of a specific eating disorder.

Also alarming is the rate at which treatment centers are seeing more and more cases of people with ED-DMT1 who have become ill to the point of requiring intervention at the inpatient, residential, or partial hospitalization levels of care.

The statistics vary slightly from study to study and depending on the criteria used, but in each case the numbers are quite high. A study by Patricia Colton, M.D., a psychiatrist at the Eating Disorders Program at Toronto General Hospital, found that 7-35% of girls and women with type 1 diabetes met the criteria for what is termed a “sub-threshold” eating disorder, meaning they display symptoms of an eating disorder but may not meet the full criteria. In that study 0-11% met the criteria for a full-syndrome eating disorder. These are pretty dramatic numbers when you compare them to the non-diabetic population. Rates in the general female population vary from 1-2% for bulimia nervosa and 0.5-1% for anorexia nervosa. It’s been reported that girls with type 1 diabetes are twice as likely to be diagnosed with an eating disorder compared to their non-diabetic peers.

So we see that people with type 1 diabetes are at a much higher risk of developing an eating disorder than the non-diabetic population. Women appear to be at higher risk than men, and the pre-teen and teen years are a particularly vulnerable time.

What causes ED-DMT1?

There is no one single factor that causes an eating disorder to develop. There is definitely a genetic component. Also, certain personality traits can increase a person’s risk of developing an eating disorder. Sometimes a traumatic event such as a divorce or the loss of a loved one can trigger an eating disorder in a susceptible individual.

As mentioned above, having type 1 diabetes puts a person at increased risk for developing an eating disorder—but the question is why? What we find is that there are several contributing factors. A major one is the necessary emphasis on food and dietary restraint associated with the management of the disease. Carbohydrate counting and meal planning are important parts of diabetes management and this can create an unhealthy focus on food, numbers, and control. Also, there is often some weight gain associated with the initiation of insulin treatment, and this can be very uncomfortable physically and emotionally. Then there are the psychological and emotional effects of having to manage a chronic medical condition such as type 1 diabetes, which there is no precise way to measure but certainly has an impact. We do know that depression and anxiety are common with both type 1 diabetes and an eating disorder diagnosis. Lastly, there is the temptation factor. Unfortunately, insulin manipulation is an easy and effective, although dangerous, method of weight loss, which makes it difficult to resist if someone is struggling with eating disordered thoughts or poor body image.

What are the clinical signs and symptoms (not including complications)?

The most salient clinical sign of the dual diagnosis of ED-DMT1 is weight loss. Another major sign would be poor blood-glucose control, especially if the person previously had good control. People with chronic insulin deficiency, in this case self-imposed, experience hyperglycemia, recurrent or persistent ketonuria, and these symptoms can often lead to recurrent episodes of diabetic ketoacidosis (DKA). Symptoms can also include polydipsia (excessive thirst), polyuria (frequent urination) and polyphagia (increased hunger). Other signs that clinicians look for are rapid weight loss, growth failure in adolescents, severe recurrent episodes of hypoglycemia, and higher than usual hemoglobin A1c levels (especially in spite of good blood sugar records, which may be falsified by the individual). General signs of disordered eating such as dieting, binge eating, abnormal behaviors or rituals around food, or refusal to eat in the presence of others could be indicators of a problem. Constant or frequent talk about weight, body image, exercise and/or food is also a sign.

Aside from weight loss, are there any visible signs, symptoms, or behaviors? 

Besides weight loss, there are no specifically distinguishing visible signs of the dual diagnosis of ED-DMT1 that would make a healthcare professional or lay person recognize individuals with this diagnosis. Some “tip offs” may include recurrent or chronic acetone breath, wasting of muscle mass that comes with the weight loss, frequent urination, frequent thirst, and “not looking well.” At times in which these patients are in DKA, they may appear acutely ill, dehydrated, and may even show altered mental status (such as not seeming like themselves).

There could also be behavioral signs such as secretive behavior, especially surrounding meals and insulin administration, refusal to eat around other people, or hoarding of food. Also failure to attend medical appointments or to bring type 1 diabetes management records and/or food diaries to appointments could indicate that something is wrong. Although not specific to ED-DMT1, a depressed mood, social withdrawal, or deterioration in school or work performance could also be signs of a problem. There may be physical signs such as scarring on the top of the hands from inducing purging (called Russell’s sign), or lanugo (the soft fine hair that develops to keep an undernourished body warm). These are signs of an eating disorder, but not specific to ED-DMT1.

Most people with type 1 diabetes are very familiar with the complications that can arise from their illness. What are the complications that can arise from the dual diagnosis of ED-DMT1?

There are both acute and chronic complications associated with the dual diagnosis. Both acute and chronic complications can be serious and even deadly. Insulin deficiency leads to hyperglycemia or elevated levels of glucose in the bloodstream. Hyperglycemia, in turn, leads to damage of small vessels, so called “microvascular damage” and damage of nerve cells, specifically peripheral nerves.  In type 1 diabetes, the rate at which microvascular disease and peripheral nerve damage occurs has been more closely correlated with the length of suffering from the disease.

In the dual diagnosis of ED-DMT1, the degree of hyperglycemia allowed or induced by these patients is so significant, that the rate of onset and later progression of severity of both microvascular disease and peripheral nerve damage is greatly accelerated. The complications most frequently seen in all types of diabetes are damage to the retina of the eye, damage to the kidney, and damage to the heart and these are related to microvascular disease. The other frequently seen complication is small nerve damage (peripheral neuropathy) which can manifest with pain, tingling, and even numbness of hands and feet. These complications can and do occur in all forms of diabetes but are accelerated in their time of onset and progression in the dual diagnosis of ED-DMT1.

Another unfortunate but important concern for this group of patients is the increased mortality risk that they experience. In one study, the risk of death for the dual diagnosis of ED-DMT1 was 17-fold compared to type 1 diabetes alone and seven-fold compared to anorexia nervosa alone. This is alarming and a reflection of the real risk brought about the co-existence of these two diagnoses. Serious and premature complications of type 1 diabetes and a significantly increased risk of premature death make the dual diagnosis of ED-DMT1 a very serious condition. In summary, complications for those with ED-DMT1 can be divided into acute and chronic complications of insulin deficiency and hyperglycemia. The acute complications include polyuria, polydipsia, weight loss, and DKA. The chronic complications are related to diabetic microvascular disease often affecting the eyes, the kidneys, and the heart, and peripheral neuropathy.