The prevalence of Type 2 diabetes is not increased in normal-weight women with PCOS.

STUDY QUESTION

Is oral glucose tolerance test (OGTT) needed in all women with polycystic ovary syndrome (PCOS)?

SUMMARY QNSWER

OGTT is not routinely needed in women with PCOS and BMI < 25 kg/m2.

WHAT IS KNOWN ALREADY

PCOS is associated with insulin resistance and increased prevalence of prediabetes and Type 2 diabetes (T2D) which is closely linked to obesity and possibly age, ethnicity and PCOS phenotype. Several guidelines recommend OGTT upon diagnosis of PCOS and during follow-up.

STUDY DESIGN, SIZE, DURATION: A Nordic cross-sectional study including 876 women.

PARTICIPANTS/MATERIALS, SETTING, METHODS: The 876 Nordic women with PCOS, aged 14-57 years, were examined for T2D and prediabetes (impaired glucose tolerance [IGT] or impaired fasting glucose (IFG) by OGTT.

MAIN RESULT AND THE ROLE OF CHANCE

Of all study subjects 3% (23/876) had T2D, 23% (204/876) prediabetes and 74% (649/876) had normal glucose tolerance (NGT). Increased BMI and waist circumference were significantly (P < 0.001) associated with prevalence of prediabetes and T2D. No normal-weight woman (BMI < 25 kg/m2) was diagnosed with T2D. The prevalence of BMI ≥ 25 kg/m2 was 66% (578/ 876). 91% of women (21/23) with T2D had BMI ≥ 30 kg/m2. Testosterone levels and PCOS phenotype did not predict 2-h glucose levels during OGTT after adjustment for BMI and age.

LIMITATIONS, REASONS FOR CAUTION: The present study included cross-sectional data and prospective studies are needed to confirm our results. These results may not apply to populations of other ethnic origin.

WIDER IMPLICATIONS OF THE FINDINGS

Routine OGTT may not be indicated in normal-weight women with PCOS.

STUDY FUNDING/COMPETING INTEREST(S): None.

TRIAL REGISTRATION NUMBER

N/A.