Diabetes and impaired glucose tolerance in patients with polycystic ovary syndrome-a long term follow-up

Abstract

BACKGROUND: The overall risk of developing diabetes mellitus and glucose intolerance seems to be higher in women with polycystic ovary syndrome (PCOS) than in healthy women. The aim of this long-term follow-up study was to examine glucose tolerance and insulin sensitivity in middle-aged women previously diagnosed with PCOS in comparison with age-matched healthy controls. Methods Women diagnosed with PCOS between 1987 and 1995 were invited to participate in the study. A total of 84 PCOS patients and 87 control subjects participated. Anthropometric (BMI, waist/hip ratio) and metabolic parameters (oral glucose tolerance test) were measured. Insulin sensitivity was expressed by the Matsuda index and beta cell function by the insulinogenic index. PCOS women were subgrouped according to phenotype at the index assessment (with or without hyperandrogenism) and persistence of PCOS symptoms at the follow-up (persisting or resolved PCOS). Results Eighteen (21.4%) PCOS patients and four (4.5%) controls had developed type 1 or type 2 diabetes or impaired glucose tolerance (IGT) at the follow-up investigation (P < 0.05). Matsuda insulin sensitivity index was lower and the insulinogenic index was increased in women with previously diagnosed PCOS compared with control subjects. In addition, PCOS patients with or without hyperandrogenism, and PCOS patients with persisting and resolved PCOS all had lower Matsuda insulin sensitivity index and increased insulinogenic index in comparison with controls. CONCLUSIONS IGT and type 2 diabetes occurred more often in PCOS patients. Independent on PCOS phenotype at index assessment and persistence of PCOS symptoms at the follow-up investigation, women with PCOS had lower insulin sensitivity but a well-preserved beta cell function in comparison with control subjects. © The Author 2011. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved.