An important warning about atypical, or second-generation, antipsychotic drugs and a connection to increased risk for diabetes and hyperglycemia didn't make it to primary care physicians, according to a new study(archpsyc.ama-assn.org) in the Archives of General Psychiatry.
In late 2003, the FDA identified a connection between atypical antipsychotics and an increased risk for diabetes. At the same time, the American Diabetes Association, or ADA, and the American Psychiatric Association, or APA, published a consensus statement describing the risks associated with the medications and establishing a monitoring protocol for all patients taking the drugs. The associations recommended physicians take a baseline assessment, including fasting plasma glucose level and fasting lipid profile.
Subsequently, the FDA sent letters to physicians to alert them to the new warning. However, according to the study, the letters were sent to "neuropsychiatric health care professionals."
Surveys of psychiatrists after the warning showed a high level of knowledge concerning the need for metabolic testing, with up to 80 percent reporting that they monitored glucose and lipid levels in patients taking atypical antipsychotic drugs.
The authors of the study theorize that although psychiatrists -- the primary target of the FDA's communication -- were informed, primary care physicians, who were more likely to be ordering the necessary lab tests and providing general medical care, may have had lower awareness because they were not contacted by the FDA.
According to the study, the population prevalence of dyslipidemia, hypertension, obesity and type 2 diabetes mellitus is approximately 1.5 to two times higher in individuals with serious mental illness than in the general population. Thus, more frequent metabolic monitoring is indicated.
In January 2002, 26.9 percent of patients starting treatment with atypical antipsychotic drugs had baseline glucose testing, and 10 percent had baseline lipid testing, according to the study. Baseline glucose testing rates did not increase during or after the FDA warning period. Baseline lipid testing increased 1.7 percent during the warning period, but remained constant after the warning.
"The existing baseline screening and ongoing monitoring of glucose and lipid levels in these patients was already pretty low, and the FDA warning really had no impact in changing that," said Daniel Hartung, an assistant professor of pharmacy instruction in the College of Pharmacy at Oregon State University and one of the study's authors, in a news release(oregonstate.edu).
Although the consensus statement from the ADA and APA did not result in increased baseline testing or monitoring, there were changes in prescribing practices associated with the FDA's warning. Use of olanzapine, a drug marketed as Zyprexa that is associated with greater metabolic risk, declined significantly, according to the study.
There also was a spike in the use of aripiprazole, which is marketed as Abilify and Abilify Discmelt, although the authors note a formulary change in California -- one of three states involved in the study -- may have been responsible for much of that increase.