Abnormal glycosylated hemoglobin as a predictive factor for glucose metabolism disorders in antipsychotic treatment

Abstract

The aim of this study was to observe the changes in glucose metabolism after antipsychotic (APS) therapy, to note the influencing factors, as well as to discuss the relationship between the occurrence of glucose metabolism disorders of APS origin and abnormal glycosylated hemoglobin (HbA₁c) levels. One hundred and fifty-two patients with schizophrenia, whose fasting plasma glucose (FPG) and 2-h plasma glucose (2hPG) in the oral glucose tolerance test (2HPG) were normal, were grouped according to the HbA₁c levels, one normal and the other abnormal, and were randomly enrolled into risperidone, clozapine and chlorpromazine treatment for six weeks. The FPG and 2hPG were measured at the baseline and at the end of the study. In the group with abnormal HbA1c and clozapine therapy, 2HPG was higher after the study [(9.5±1.8) mmol/L] than that before the study [(7.2±1.4) mmol/L] and the difference was statistically significant (P⟨0.01). FPG had no statistically significant difference before and after the study in any group (P⟩0.05). HbA₁c levels and drugs contributing to 2HPG at the end of study had statistical cross-action (P⟨0.01). In the abnormal HbA₁c group, 2HPG after the study was higher in the clozapine treatment group [(9.5±1.8) mmol/L] than in the risperidone treatment group [(7.4±1.7) mmol/L] and the chlorpromazine treatment group [(7.3±1.6) mmol/L]. The differences were statistically significant (P⟨0.01). In the normal HbA₁c group there was no statistically significant difference before and after the study in any group (P⟩0.05). 2HPG before [(7.1±1.6) mmol/L] and after the study [(8.1±1.9) mmol/L] was higher in the abnormal HbA₁c group than in the normal HbA₁c group [(6.2±1.4) mmol/L vs (6.5±1.4) mmol/L] with the difference being statistically significant (P⟨0.01 vs P⟨0.001). As compared with normal HbA₁c group, the relative risk (RR) of glucose metabolism disease occurrence was 4.7 in the abnormal HbA₁c group with the difference being statistically significant (P⟨0.001). Patients with abnormal HbA₁c are more likely to have a higher risk of having glucose metabolism disorders after APS treatment.