The Influence of Prepubertal Onset of Type 1 Diabetes and Age of Menarche on Polycystic Ovary Syndrome Diagnosis.

Context: Higher prevalence of polycystic ovary syndrome (PCOS) in women with type 1 diabetes (T1DM) is linked to exogenous insulin, especially when diabetes is diagnosed before puberty.

Objective: The study evaluates the impact of prepubertal onset of T1DM and insulin therapy on PCOS diagnosis and phenotypic characteristics in women with T1DM.

Design, Setting, And Patients: We studied 83 women with T1DM (age 26 ± 5 years, BMI 24 ± 3 kg/m2) 36 with premenarchal (PM) onset of T1DM [17 with PCOS diagnosed (PCOS+PM) and 19 without PCOS (noPCOS+PM)] and 47 women with postmenarchal onset of T1DM [24 with PCOS (PCOS-noPM) and 23 without PCOS (noPCOS-noPM)].

Outcome Measurements: Clinical examination, assessment of serum sex hormones, glycated hemoglobin (HbA1c) and ultrasonographic evaluation of the ovaries were performed in all women.

Results: Applying Rotterdam criteria, 49% of women with T1DM were diagnosed with PCOS. There were no differences in hormonal profile and ovarian parameters between PCOS+PM and PCOS-noPM. Women with T1DM+PM had higher insulin dose/24 h and U/kg bw/24 h than T1DM-noPM (P-values = 0.014 and 0.001, respectively). Both PCOS+PM and noPCOS+PM groups had higher insulin dose U/kg bw/24 h in comparison to PCOS-noPM (P-values = 0.004 and = 0.006, respectively). In multivariable logistic regression analysis, age of menarche [odds ratio (OR): 0.672; 95% confidence interval (CI): 0.465-0.971] and HbA1c (OR: 0.569; 95% CI: 0.383-0.846) were associated with the diagnosis of PCOS.

Conclusions: There were no differences in the prevalence of PCOS between T1DM+PM and T1DM-noPM; however, earlier menarche might have an influence on PCOS diagnosis in women with T1DM.