Brittle Diabetes Mellitus
Thomas Higgins, M.D.
Brittle Diabetes is a subjective term and the diagnosis often depends on the experience of the patient, family and physician involved. The most useful definition of brittle diabetes is a functional one: "the patient whose life is constantly disrupted by episodes of hyper- or hypoglycemia, whatever their cause". While these patients are rare (less than one percent diabetics), they cause a considerable burden on hospital, social, and family resources due to multiple hospital admissions.
Many early studies tried to identify possible physiological mechanisms for the brittleness but with increasing study, it has become clear that the majority of cases are due to psychological factors. Metabolic abnormalities are a rare cause of poor glycemic control.
Brittleness may be in the form of hyperglycemic brittleness, hypoglycemic brittleness or a combination of both. Brittle diabetics followed over a long period of time have been noted to have certain characteristics:
- Most patients were consistent in whether their recurrent episodes were hyperglycemic or hypoglycemic in nature. Only occasional patients showing "mixed brittleness".
- Women predominate in most studies of brittle diabetes but men frequently also are found to be brittle. In my own experience, brittleness is more common during puberty in both sexes.
- There is a significant mortality rate. Among survivors, the insulin dose tends to drop over time and episodes of hyperglycemia and severe hypoglycemia become less frequent.
- Diabetic complications seem to be more frequent in brittle diabetics and are most likely related to poorer metabolic control.
Cause of Brittle diabetes:
It is clear that the brittleness in most patients is related to a specific unhappy life situation; when this resolves, so does the brittleness.
Hyperglycemic brittleness is rarely related to a chronic cryptic infection.
Hypoglycemic brittleness is rarely related to diabetic gastroparesis where the stomach has a delay in emptying or hypoglycemic unawareness where the patient can not sense a low blood sugar.
The approach to management will obviously vary depending on the specific cause in each case. In evaluating a patient with brittle diabetes (who may have mountainous medical records!), it may be beneficial to start fresh with a new physician and diabetes care team. A fresh look is helpful in remaining objective, decreasing the ability of the patient to manipulate the care team and possibly spot a metabolic cause which may have been missed.
It is important to take a detailed history and do a detailed physical exam. It should also be determined if there was a period of "stable" diabetes preceding the brittleness, and what happened in the patient's life circumstances coincident with the onset of brittleness.
A diabetic educational assessment is important to evaluate whether the patient knows how to manage diabetes, and whether the current insulin regimen is reasonable. In addition, as many as one third of patients with brittle diabetes have been found to have a "communication disorder" (which can be diagnosed by speech language pathologists) as the major cause of their brittleness; specific treatment is beneficial in 75% of cases.
A psychological evaluation is always warranted, since psychotherapy has been shown to be effective in selected patients. Family counseling is also often necessary.
For severe cases of brittle diabetes, a structured hospital admission may be necessary. Generally these admissions are prolonged, lasting for two to three weeks. Pre-hospital planning is important and insurance pre-certification is often necessary. Early in the hospital course, the patient must be monitored closely and have all diabetes care done by the hospital staff. Gradually, the patient is allowed to become more involved in his or her own care. Intensive diabetes education is necessary as well as ongoing psychological support.