The utility of fasting plasma glucose to identify impaired glucose metabolism in women with polycystic ovary syndrome

We evaluated the utility of impaired fasting plasma glucose as defined by ADA to identify women with polycystic ovary syndrome (PCOS) affected by impaired glucose metabolism (i.e. impaired fasting glucose, impaired glucose tolerance and diabetes mellitus). In 330 women with PCOS, according to ESHRE criteria, an oral glucose tolerance test was done. Impaired fasting glucose was present in 36 women (12%), impaired glucose tolerance in 29 women (8.8%) and diabetes mellitus in 10 women (3%), 4 of them have fasting glucose higher than 7 mmol/l. The combination of impaired fasting glucose and impaired glucose tolerance was seen in 5 women (1.5%). The sensitivity of impaired fasting glucose for the detection of impaired glucose tolerance was 24% and specificity 91.8%. When fasting glucose above 5.6 mmol/l was used as the screening criterion, 28/35 subjects (80%) would have been missed. We conclude that fasting plasma glucose is not sufficiently sensitive for the detection of impaired glucose tolerance and diabetes mellitus type 2 in women with PCOS.