Endocrine Abstracts

Background: Despite the strong preclinical rationale, there are only very few data considered the utility of metformin, as a potential pain therapeutic in humans. The aim of this study was to determine, the association between metformin therapy and pressure pain threshold (PPT) in lean polycystic ovary syndrome (PCOS) women. We hypothesized that metformin therapy in lean PCOS women increases pressure pain threshold.

Materials and methods: Twenty-seven lean PCOS women with free androgen index (FAI) phenotype > 5 and 18 lean healthy controls were enrolled to the study. Fifteen of PCOS women were randomly assigned to be treated with metformin 1500 mg daily for 6 months. PPT and plasma β-endorphins levels were measured in all women at the beginning of the study and after 6 months observation.

Results: We observed increase in pressure pain threshold values measured on deltoid and trapezius muscle in PCOS with metformin group after 6 months metformin administration, (4.81±0.88 kg/cm², P<0.001 on deltoid muscle and 5.71±1.16 kg/cm² on trapezius muscle). We did not observe any significant changes in PPT values in PCOS without treatment group and controls. We did not observe any significant changes in serum β- endorphin levels in any studied groups during 6 months observation.

Conclusion: We conclude that metformin therapy increases pressure pain threshold in PCOS lean women, without affecting β- endorphin plasma concentration. Our results may suggest the potential role of metformin in pain therapy. We propose that larger, randomized studies, on metformin impact on pain perception should be performed.