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

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.