Powerpoint template for scientific posters Swarthmore College

1
Specific Effect of Antipsychotics on Pituitary
Volume A Structural MRI Study Rhonda M.
El-Sheikh1, Frank P. MacMaster1, Ameet R.
Upadhyaya1, Jeffrey Nutche2, David R.
Rosenberg1, Matcheri S. Keshavan11Psychiatry
Behavioral Neurosciences, Wayne State University
School of Medicine, Detroit, MI,2Western
Psychiatric Institute Clinic, University of
Pittsburgh Medical Center, Pittsburgh, PA

• Results
• B. Risperidone vs. Olanzapine Analysis (PSY)
• Risperidone is known to be a prolactin-elevating
  antipsychotic drug, whereas olanzapine is known
  to be prolactin-sparing
• Within the PSY group, a comparison was made
  between patients taking risperidone, and those
  taking olanzapine
• 14 subjects out of 18 total were primarily taking
  either risperidone or olanzapine
• Interestingly, risperidone produced larger
  increases in pituitary volume as opposed to
  olanzapine (Figure 3)
• 13 increase 3 increase respectively

• Introduction
• Prolactin is a hormone secreted by the lactotroph
  cells of the anterior pituitary gland
• Dopamine is the main inhibitory factor for
  prolactin release
• Any process that diminishes the production of
  dopamine or its flow to the pituitary may result
  in elevated blood prolactin levels
• Antipsychotic drugs act as dopamine antagonists
  by blocking the D2 receptors on the lactotroph
  cells
• When the inhibitory effect of dopamine on
  prolactin release is lost, hyperprolactinaemia
  occurs
• Objective
• Novel antipsychotics such as risperidone are
  known to affect pituitary function leading to
  robust prolactin elevations
• Increased prolactin may lead to structural
  alterations in pituitary volume
• However, to date, no imaging study has examined
  the effect of antipsychotics on pituitary volume
  or the specificity of such effects in an
  antipsychotic naïve population
• Hypothesis
• Since antipsychotic drugs are known to elevate
  prolactin levels, we postulate an increase in
  pituitary volume in patients using these
  medications

• Results
• First Episode Psychotic Subjects (PSY) vs.
  Healthy Controls
• Pituitary volume significantly increased in the
  PSY subjects after successful treatment, as
  opposed to healthy controls
• t17 2.44, p 0.026, 11 increase 1
  increase respectively
• Mean pituitary volumes for PSY sample (Figure 2)
• Pre pituitary volume
• Mean volume s.d. 0.57 0.15 mm3
• Post pituitary volume
• Mean volume s.d. 0.63 0.20 mm3

• Conclusions
• Pituitary volume increases appear specific to
  antipsychotic treatments, especially prolactin
  elevating drugs such as risperidone in contrast
  to prolactin sparing drugs similar to olanzapine
  
• In one of our previous studies, we have shown
  that pituitary volume is reduced in antipsychotic
  naïve patients with first episode psychosis
• However, no study has examined the effect of
  antipsychotics on pituitary volume or the
  specificity of such effects in treatment naïve
  patients
• Pituitary volumes may be a biomarker for
  treatment related neuroendocrine dysfunctions
• Future studies should combine neuroendocrine
  measures with pituitary volumetric measures

• Methods
• Pituitary volumes were measured in a series of
  five samples using the BRAINS2 software (Table 1)
• Measurements were obtained on 1.5 mm thick
  T1-weighted coronal images from a 1.5T GE
  scanner. The tracings were then cross checked in
  the sagittal view (Figure 1)
• Pituitary volumes were measured at two separate
  time points for each sample. The duration between
  the baseline, and follow-up measurements is
  listed in weeks. The percent change in pituitary
  volume was then computed. The measured pituitary
  volumes include
• A. Before and after treatment samples
• Treatment naïve first episode psychotic (PSY)
  patients (primarily taking risperidone or
  olanzapine)
• Obsessive compulsive disorder (OCD) patients
• Major depressive disorder (MDD) patients
• Attention deficit hyperactivity disorder (ADHD)
  patients
• B. Unmedicated healthy controls

• References
• M. Hummer, and J. Huber. 2004. Hyperprolactinaemia
  and antipsychotic therapy in schizophrenia.
  Current Medical Research and Opinion 20189-197.
• P.M. Haddad, and A. Wieck. 2004.
  Antipsychotic-Induced Hyperprolactinaemia. Drugs
  64 202291-2314.
• A. Upadhyaya, R. El-Sheikh, M. Keshavan. 2005.
  Pituitary Volume in First-Episode Psychosis A
  Structural MRI Study. Society of Biological
  Psychiatry conference.
• Magnotta VA, Harris G, Andreasen NC, O'Leary DS,
  Yuh WT, Heckel D.  2002. Structural MR image
  processing using the BRAINS2 toolbox. Comput.
  Med. Imaging Graph 26(4)251-64.
• B. Kinon, J. Gilmore, H. Liu, and U. Halbreich.
  2003. Hyperprolactinaemia in response to
  antipsychotic drugs characterization across
  comparative clinical trials. Psychoneuroendocrinol
  ogy 2869-82.
• U. Halbreich, B.J. Kinon, J.A. Gilmore, and L.S.
  Kahn. 2003. Elevated prolactin levels with
  schizophrenia mechanisms and related adverse
  effects. Psychoneuroendocrinology 2853-67.
• C. Canuso, M. Hanau, K. Jhamb, and A. Green.
  1998. Olanzapine Use in Women with
  Antipsychotic-Induced Hyperprolactinemia. Am J
  Psychiatry 1551458
• University of Michigan Health System. 2005.
  Pituitary Conditions Treatments Educational
  Information for Patients. http//www.med.umich.edu
  /neurosurgery/pituitary/conditions.htm
• For further Information
• Please contact
• Rhonda El-Sheikh relsheik_at_med.wayne.edu or
• Dr. Keshavan mkeshava_at_med.wayne.edu
• Funding Source NIMH

Fig. 3 This graph illustrates the mean percent
increase in pituitary volume for subjects taking
risperidone (13), subjects taking olanzapine
(3), and unmedicated healthy controls (1). The
duration between baseline, and follow up
pituitary measurements was 52 weeks.
Fig. 2 A plot showing the mean pituitary volume
for the first episode psychotic subjects at both
the pre and post time points. Following
treatment for 52 weeks, the PSY group had a mean
increase in pituitary volume of about 11.
Fig. 1 Sample tracing of the pituitary gland
using the BRAINS software.
Table 1 The table shows the five samples used
to obtain volumetric pituitary measurements.
Within each sample, each subject was scanned at
two different time points (once at baseline, and
once at a follow-up time point). The duration
between both baseline, and follow-up scans for
each subject is denoted in weeks. Pituitary
volumes were measured at both time points and the
percent change was then calculated. Out of the
four samples receiving medication, the PSY group
showed the largest increase in pituitary volume
(11) compared to the OCD (1), MDD (3), and
ADHD (1) groups.