Glucose Dysregulation May Occur Early in Patients With Schizophrenia

Although individuals with schizophrenia are significantly more likely to develop type 2 diabetes than those in the general population, it is unclear whether the illness alone confers an inherent risk for glucose dysregulation. Findings from a meta-analysis published in January in JAMA Psychiatry suggest that individuals with schizophrenia may already be experiencing glucose dysregulation at the onset of the psychotic condition.

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“This is a wake-up call that we need to consider diabetes prevention right from the onset of schizophrenia,” said Toby Pillinger, M.R.C.P., a clinical researcher at the Institute of Psychiatry, Psychology, and Neuroscience at King’s College London and lead author of the meta-analysis. Such efforts include routine diabetic screening and educating patients about the importance of a healthy diet and exercise, he told Psychiatric News.

Pillinger and colleagues conducted a systematic review of case-control studies reporting on fasting plasma glucose levels, fasting insulin levels, insulin resistance, and hemoglobin A1c (HbA1c) levels in patients with first-episode schizophrenia. Patients who had no or minimal antipsychotic exposure (14 days or less on antipsychotics) were compared with controls. A total of 16 case-control studies were included in the analysis, including 731 patients and 614 controls.

Hofstra Northwell School of Medicine

Fasting plasma glucose levels, plasma glucose levels after an oral glucose tolerance test, fasting plasma insulin levels, and insulin resistance were all significantly elevated in patients with schizophrenia compared with controls. HbA1c levels were not altered in patients compared with controls.

“These results underscore the urgent mandate for mental health care professionals to routinely screen people with psychotic disorders for all aspects of glucose dysregulation, including increases in body mass index, fasting blood glucose, fasting blood lipids, and blood pressure,” Christoph Correll, M.D., a professor of psychiatry at Hofstra Northwell School of Medicine, said during an interview with Psychiatric News. Correll, who was not involved with the study, noted that metabolic risk factors should be assessed at onset of illness and at least once annually. He explained that there should be “more frequent assessments in people who are obese, gain at least 7 percent of their baseline weight, or have abnormal glucose, lipid, or blood pressure results.”

Correll added that using caution when prescribing medication and monitoring metabolic risk factors must be top priorities when treating any individual with a psychotic disorder, even in very young people and those who are of normal weight.

The meta-analysis was supported by the Medical Research Council. ■