Functional neuroimaging of emotional processing in women with polycystic ovary syndrome: a case-control pilot study

Abstract

Objective: To evaluate emotional processing in women with insulin-resistant polycystic ovary syndrome (IR-PCOS) and its relationship to glucose regulation and the mu-opioid system.

Design: Case-control pilot.

Setting: Tertiary referring medical center.

Patient(s): Seven women with IR-PCOS and five non-insulin-resistant controls, aged 21-40 years, recruited from the general population.

Intervention(s): Sixteen weeks of metformin (1,500 mg/day) in women with IR-PCOS.

Main outcome measure(s): Assessment of mood, metabolic function, and neuronal activation during an emotional task using functional magnetic resonance imaging (fMRI), and mu-opioid receptor availability using positive emission tomography (PET).

Result(s): We found that insulin-resistant PCOS patients [1] had greater limbic activation during an emotion task than controls (n = 5); [2] trended toward decreased positive affect and increased trait anxiety; [3] after metformin treatment, had limbic activation that no longer differed from controls; and [4] had positive correlations between fMRI limbic activation during emotional processing and mu-opioid binding potential.

Conclusion(s): Patients with IR-PCOS had greater regional activation during an emotion task than the controls, although this resolved with metformin therapy. Alterations in mu-opioid neurotransmission may underlie limbic system activity and mood disorders in IR-PCOS.

Trial registration: ClinicalTrials.gov NCT00670800.

Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

Functional MRI limbic activation with emotional processing in women with IR-PCOS at baseline (n = 7) and after metformin (n = 7) and in control women (n =5). Images were collected from a whole brain t test analysis of pre-metformin-control subtraction images, at a viewing threshold of P<.01. *Student's t test (IR-PCOS at baseline vs. controls). **Student's t test (IR-PCOS after metformin vs. controls). †Paired t test (IR-PCOS before and after metformin).

Figure 2

Functional MRI limbic activation with emotional processing in women with IR-PCOS at baseline and after metformin administration. Dark gray: IR-PCOS at baseline. Light gray: IR-PCOS after metformin.