Glucoregulation in normal weight schizophrenia patients treated by first generation antipsychotics

INTRODUCTION Schizophrenia patients are at greater risk of obesity, diabetes mellitus (DM), lipid abnormalities and cardiovascular disorders. The metabolic complications in patients are associated with several risk factors: family history of DM, lifestyle, smoking, dietary habits, physical inactivity, but also with antipsychotic medication. In literature, most publications have been focused on the effects of the second generation antipsychotics (SGA) on glucose metabolism. However, less attention has been paid to abnormality in glucoregulation, patients with schizophrenia treated with the first generation antipsychotics (FGA). OBJECTIVE The present study evaluated glucose metabolism in normal weight schizophrenia patients treated with FGA. METHOD The cross-sectional study included 18 patients (FGA treated) and 20 healthy controls with neither group differences in sex distribution, age, nor in BMI. Inclusion criteria were normal BMI (20-25 kg/m(2)) The glucose levels, insulin levels and growth hormone levels during oral glucose tolerance test (OGTT) were measured. RESULTS Fasting glucose and insulin levels did not differ significantly between groups. Groups differed in OGTT glucose and insulin peak and area under curve (AUC), level of significance p<0.05 (patients vs. controls: glucose peak 8.3 +/- 0.4 vs. 6.9 +/- 0.5 mmol/l, glucose AUC 758 +/- 28 vs. 640 +/- 36 mU/l/120 min; insulin peak in patients 92.7 +/- 15.6 mU/l; insulin AUC 6060 +/- 1016 mU/l/120 min, insulin peak in controls 47.9 +/- 6.5 mU/l; insulin AUC 2597 +/- 256 mU/l/120 min). CONCLUSION Patients with schizophrenia, although with normal body mass index, are at high risk of abnormal glucose regulation. Not only SGA increase the risk of impaired glucoregulation and metabolic syndrome, but this may also be due to FGA or schizophrenia per se.