Determinants of interleukin-6 and C-reactive protein vary in polycystic ovary syndrome, as do effects of short- and long-term metformin therapy.
OBJECTIVE
Circulating levels of interleukin-6 (IL-6) and C-reactive protein (CRP) were determined in 59 women with polycystic ovary syndrome, of whom 37 were retested after receiving metformin for 6 weeks and 6 months, to ascertain the response of these inflammatory markers to weight loss and insulin sensitization.


RESULTS
IL-6 levels correlated significantly with body mass index (BMI; r = 0.55), homoeostasis model insulin resistance index (HOMA-R; r = 0.47) and CRP (r = 0.59). On multiple regression analysis, adiposity rather than IL-6 accounted for most of the variability of CRP independently of insulin resistance, while IL-6 remained closely with adiposity. After 6 weeks of metformin therapy (n = 37) there was a significant reduction in BMI (p < 0.001), waist (p < 0.001) and CRP (p < 0.01), while at 6 months there was not only a significant reduction in BMI and waist but also in HOMA-R (p = 0.01) and IL-6 levels (p < 0.01) with no further reduction of CRP.


CONCLUSIONS
In polycystic ovary syndrome, obesity rather than IL-6 or insulin resistance is the main determinant of CRP. While short-term metformin therapy facilitates weight loss with a concomitant reduction in CRP, long-term therapy results in a reduction of IL-6 and insulin resistance. Metformin-associated reduction of CRP levels prior to any significant changes in insulin resistance or IL-6 perhaps involves different mechanisms of action.
Tsilchorozidou
Tasoula
T
Department of Endocrinology, Diabetes and Metabolism, University College London Hospitals, London, UK.
Mohamed-Ali
Vidya
V
Conway
Gerard S
GS
D050154:Adiposity / Q000187:drug effects / Q000502:physiology; D000328:Adult; D002097:C-Reactive Protein / Q000032:analysis* / Q000378:metabolism; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000188:drug therapy; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007333:Insulin Resistance / Q000502:physiology; D015850:Interleukin-6 / Q000032:analysis / Q000097:blood*; D008597:Menstrual Cycle / Q000187:drug effects / Q000502:physiology; D008687:Metformin / Q000627:therapeutic use*; D011085:Polycystic Ovary Syndrome / Q000097:blood* / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
D007004:Hypoglycemic Agents; D015850:Interleukin-6; D002097:C-Reactive Protein; D008687:Metformin