December 14, 2006

Diabetes Screening Process Validated for Patients With Schizophrenia

Data shows a high incidence of hyperglycemia and diabetes among patients with schizophrenia and schizoaffective disorder regardless of antipsychotic use. Currently, the American Diabetes Association (ADA) and the American Psychiatric Association (APA) advise that all patients with these disorders be screened with a simple blood test, called a fasting plasma glucose (FPG) test, measuring glucose levels. However, other data has been emerging showing that the FPG test is sometimes insufficient for detecting glucose metabolism abnormalities in this patient population, and therefore some doctors are suggesting that the oral glucose tolerance test (OGTT), considered to be the "gold standard" test for diabetes and glucose metabolism problems, must be used in some cases. However, guidelines for doing so is lacking in the United States.

The World Health Organization (WHO) provides a guideline which recommends that a two step screening process be used for all patients with schizophrenia and schizoaffective disorder. Step one assesses the fasting plasma glucose (FPG) in all patients, then in those patients showing impaired fasting glucose, the OGTT must be done (step 2).

A Belgian study, published in the Journal of Clinical Psychiatry , was done on 415 patients with schizophrenia to determine how best to screen such patients for diabetes and other glucose metabolism abnormalities. The study compared the current ADA/APA guideline (test FPG) and WHO's guideline (test FPG then use OGTT under specific conditions) against the "Gold Standard" - the oral glucose tolerance test.

It should be noted that the FPG test is quickly done with one blood draw following an 8-hour fast, usually done early in the morning. On the other hand, the OGTT requires the patient to be in the lab for several hours and requires multiple blood draws. The FPG is therefore faster and less expensive than the OGTT, which is a factor in not simply screening all patients with the most effective test for detection of glucose metabolism abnormalities - the OGTT.

Using the APA/ADA guidelines (FPG test alone), only 46.2% of the cases of diabetes and glucose metabolism impairment were detected, leaving over half (53.8%) of the cases that were detected with the OGTT MISSED. In comparison, the WHO's proposed 2-step strategy detected 96.2% (only missing 3.8%) of the cases caught by using the OGTT exclusively.

Researchers Ruud van Winkel and colleagues at the Katholieke University Leuven concluded:

"The data suggest a high incidence of diabetes in patients diagnosed with schizophrenia. However, the guidelines to detect diabetes as proposed by the APA/ADA did not sufficiently detect diabetes in this specific high-risk group."

"The alternative 2-step strategy was able to detect the vast majority of diabetes cases and should therefore be considered in the clinical routine of screening and monitoring patients with schizophrenia."

Read the Full Article: Screening for Diabetes and Other Metabolic Abnormalities in Patients With Schizophrenia and Schizoaffective Disorder: Evaluation of Incidence and Screening Methods

Read about schizophrenia, diabetes and diabetes prevention and amelioration:
Psychiatric Wellness Program
Metabolic Syndrome (Diabetes) in Psychiatric Patients
New Study to Identify People With Schizophrenia who are at Risk for Type 2 Diabetes
20% of people with Schizophrenia will get Diabetes?


It is amazing that some GPs will not even send their patients for the FPG test... as if it is the doctor paying for it. What gives? Do they have some restriction from Medicaid or whatever restricting the number of patients they send for diabetes testing?

All I can suggest is that if one doctor won't send you for even that FGP test at the minimum, then ask another. Your psychiatrist can send you, and he/she should be more up-to-date on the tests you should have. It doesn't have to be your GP that requests the test.

If all else fails, print out the original article linked to, and give your doctors copies, since it shows that even the FPG test can miss over half the cases and you might even need the OGTT.

Your health is too important to ignore. And sometimes you have to be your own advocate.


Posted by: Naomi at December 22, 2006 07:25 AM

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