Reported July 30, 2009
Antipsychotic Drugs Linked to Hyperglycemia
(Ivanhoe Newswire) -- Older diabetic patients who take antipsychotic medications appear to have an increased risk of hospitalization for hyperglycemia (elevated blood glucose level), especially soon after beginning treatment, according to a new report.
The antipsychotic drugs prescribed for older adults with dementia may be associated with adverse effects, including Parkinson's disease symptoms, stroke and diabetes. "The risk of diabetes may be partly related to chronic effects of the weight gain associated with antipsychotic agents," the authors were quoted as saying. "However, case reports of acute hyperglycemia after the initiation of therapy with these drugs suggest that they may also be associated with acute glycemic [blood glucose level] changes."
Lorraine L. Lipscombe, M.D., M.Sc., of the Institute for Clinical Evaluative Sciences, University of Toronto and Women's College Research Institute at Women's College Hospital, Toronto, Ontario, Canada, and colleagues studied 13,817 individuals age 66 and older, all diabetics who began treatment with antipsychotics between April 2002 and March 2006. Each patient who was hospitalized for hyperglycemia during the observation period was considered a case and was matched with up to 10 control patients of the same age and gender who were not hospitalized during this time period. The researchers then compared the likelihood of hyperglycemia among those who were currently taking antipsychotic medications to those who had discontinued antipsychotic medications for more than 180 days.
Of the total group, 11 percent were hospitalized for hyperglycemia. Those who were currently taking antipsychotic drugs had a higher risk of hospitalization than those who had stopped the medications for more than 180 days. The risk was highest among those who were just starting antipsychotic drug treatment.
"Our study indicates that the initiation of antipsychotic therapy represents a critical period during which seniors with diabetes are particularly vulnerable to metabolic decompensation [failure of the metabolic system to function adequately]," the authors wrote. "The new use of both atypical [newer] and typical antipsychotic drugs was associated with a significant increase in hospitalizations for hyperglycemia, which appeared independent of baseline diabetes treatment and was strikingly high during the initial period of antipsychotic therapy."
Previous evidence suggests the neurotransmitter dopamine plays a role in regulating blood glucose levels. First-time antipsychotic users may experience an acute disruption in this system, leading to hyperglycemic episodes, the authors note. However, further studies are needed to confirm the cause and to identify the mechanisms involved.
"In the meantime, other options to manage behavioral symptoms of dementia should be considered among older persons with diabetes," the authors conclude. "Patients and their families should be alerted to observe for signs of glycemic decompensation when treatment with an antipsychotic agent is initiated, and enhanced glucose monitoring is recommended for all patients for whom an antipsychotic drug is prescribed, particularly after treatment initiation."
SOURCE: Archives of Internal Medicine, July 27, 2009