The effect of atypical antipsychotics on pituitary gland volume in patients with first-episode psychosis: A longitudinal MRI study
Received 27 May 2009; received in revised form 8 September 2009; accepted 11 October 2009. published online 06 November 2009.
Abstract
Background
Pituitary volume is currently measured as a marker of hypothalamic-pituitary-adrenal hyperactivity in patients with psychosis despite suggestions of susceptibility to antipsychotics. Qualifying and quantifying the effect of atypical antipsychotics on the volume of the pituitary gland will determine whether this measure is valid as a future estimate of HPA-axis activation in psychotic populations.
Aims
To determine the qualitative and quantitative effect of atypical antipsychotic medications on pituitary gland volume in a first-episode psychosis population.
Method
Pituitary volume was measured from T1-weighted magnetic resonance images in a group of 43 first-episode psychosis patients, the majority of whom were neuroleptic-naïve, at baseline and after 3months of treatment, to determine whether change in pituitary volume was correlated with cumulative dose of atypical antipsychotic medication.
Results
There was no significant baseline difference in pituitary volume between subjects and controls, or between neuroleptic-naïve and neuroleptic-treated subjects. Over the follow-up period there was a negative correlation between percentage change in pituitary volume and cumulative 3-month dose of atypical antipsychotic (r=−0.37), i.e. volume increases were associated with lower doses and volume decreases with higher doses.
Conclusions
Atypical antipsychotic medications may reduce pituitary gland volume in a dose-dependent manner suggesting that atypical antipsychotic medication may support affected individuals to cope with stress associated with emerging psychotic disorders.
ABSTRACT