Majority of Medicaid patients on antipsychotic drugs do not undergo metabolic tests, says study

Despite government warnings and professional recommendations about diabetes risks associated with second-generation antipsychotic drugs, fewer than one-third of Medicaid patients who are treated with these medications undergo tests of blood glucose or lipid levels, according to a report in the January issue of Archives of General Psychiatry, one of the JAMA/Archives journals.

In 2003, the Food and Drug Administration (FDA) began requiring a warning on labels of second-generation antipsychotics—including olanzapine, fluoxetine and risperidone—describing an increased risk for high blood sugar and diabetes, according to background information in the article. The warning stated that glucose levels should be monitored in patients with diabetes, at risk for the disease or with symptoms of high blood glucose. At the same time, the American Diabetes Association and American Psychiatric Association published a consensus statement describing the metabolic risks associated with second-generation antipsychotics and specifying a monitoring protocol for all patients receiving these medications.

Elaine H. Morrato, Dr.P.H., M.P.H., of the University of Colorado Denver, and colleagues studied laboratory claims data from the Medicaid population of three states (California, Missouri and Oregon) between 2002 and 2005. Metabolic testing (testing of blood glucose and lipid levels) rates were compared between a group of 109,451 patients receiving second-generation antipsychotics and a control group of 203,527 who began taking albuterol (an asthma drug) but not an antipsychotic. Rates were also compared before and after the FDA warning.

Initial testing rates for patients treated with second-generation antipsychotics were low—27 percent underwent glucose testing and 10 percent underwent lipid testing. The FDA warning was not associated with any increase in glucose testing and only a marginal increase in lipid testing rates (1.7 percent). "Testing rates and trends in second-generation antipsychotic-treated patients were not different from background rates observed in the albuterol control group," the authors write.

New prescriptions of olanzapine, which carries a higher metabolic risk, declined during the warning period. Prescriptions of the lower-risk drug aripiprazole increased, but this may also be attributable to the elimination of prior authorization for the drug in California during the same timeframe.

"Although this retrospective study was not able to identify or quantify reasons why laboratory screening did not increase after the FDA warnings, whereas prescribing practices did change, we might speculate on some possible explanations," the authors write. Switching to lower-risk drugs or avoiding drug treatment altogether may be simpler than the initiation of new screening procedures. In addition, although surveys have shown that psychiatrists are aware of the metabolic risk factors of these drugs, primary care providers who would generally order the necessary laboratory tests may not be.

"More effort is needed to ensure that patients who receive second-generation antipsychotic drugs are screened for diabetes and dyslipidemia and monitored for potential adverse drug effects, beginning with baseline testing of serum glucose and lipids, so that patients can receive appropriate preventive care and treatment," the authors conclude.