Insulin resistance and metabolic profile in antipsychotic naïve schizophrenia patients

Several studies have suggested insulin resistance related to dyslipidemia and body weight in drug treated schizophrenia patients. Although, insulin resistance or impaired glucose tolerance is also reported in antipsychotic naïve schizophrenia patients, their relationship with dyslipidemic changes and body weight is not well established. The present study was undertaken to examine insulin resistance in antipsychotic naïve schizophrenia patients of this region and to evaluate any association between lipid parameters and body weight with their insulin resistance, if any.

Plasma glucose, total serum cholesterol and its LDL, HDL fractions, and serum insulin levels were measured from fasting blood samples of newly diagnosed, antipsychotic naïve schizophrenia patients (n=30) and matched control group (n=25) in a hospital based case control study. Homoeostatic model assessment (HOMA) was done to evaluate insulin resistance.

Means of plasma glucose, total serum cholesterol and its LDL, HDL fractions did not vary significantly (p>0.05) between cases and control. Insulin resistance was significantly increased (p<0.05) in drug naïve cases. Multiple linear regression analyses did not show any association (p>0.05) between insulin resistance and lipid parameters.

Newly diagnosed schizophrenia patients were more prone to insulin resistance in our study population. This was not associated with any dyslipidemic changes as the lipid parameters were not elevated in them compared to the healthy controls. It was not dyslipidemia, but some other common genetic or risk factors that might be responsible for the increased insulin resistance in antipsychotic naïve schizophrenia patients in our study population.