Assessment of Insulin Resistance (IR) by Oral Glucose Tolerance Test (OGTT) in adolescents with PCOS

RUBINO C; FREIRE AV; ARCARI AJ; RODRIGUEZ ME; BALLERINI MG; BOERO L; BENGOLEA SV; BERGADÁ I; GRYNGARTEN MG; ROPELATO MG

CABA

Congreso; XXVI Annual Meeting SLEP; 2016

Sociedad Latinoamericana de Endocrinología Pediátrica

Background:Prevalence rates of IR in adults PCOS women have been reported from 44?70%, mostly in obese patients and using surrogate markers of fasting insulin concentration instead of dynamic tests. Information about the frequency of IR in adolescent cohorts measured by OGTT is limited. Objectives: To evaluate IR frequency in adolescents with PCOS by OGTT. To determine differences in androgenic and metabolic profiles in the presence or absence of IR and obesity. To determine diagnostic efficiency (DE) of HOMA-IR and fasting glucose/insulin index (G/I) in comparison to OGTT to diagnose IR. Patients and Methods: Prospective cross-sectional study. PCOS adolescents diagnosed according to AES criteria underwent a standard 75-g OGTT where glucose and insulin were measured every 30 min during 2 hs. At baseline, androgens (total and free testosterone, androstenedione, SHBG), lipids (TC, HDL, LDL, tryglicerides) and high sensitive CRP (hs-CRP) were measured. IR was defined as a peak insulin >150 μU/mL and/or 2-hour insulin level of >75 μU/mL. Normal cutoffs of HOMA-IR 7 were obtained from 20 normal cycling adolescents. ANOVA analyses was used to compare the results between groups. Data are expressed by mean±SEM. Results: Twenty three PCOS, chronological age (CA): 16.8 ± 0.40 years with gynaecological age >2.5 years were included. IR diagnosed by OGTT was found in 74% of patients (6/12, 50% with normal BMI and 100% with higher BMI). PCOS were subdivided according to IR and BMI into 3 groups: GA: n = 6, normal BMI without IR; GB: n = 6, normal BMI with IR and GC: n = 11, high BMI with IR. There were no differences in CA, hirsutism, menstrual cycle abnormalities and in the grade of hyperandrogenemia. As expected, GC showed the highest proportion of abnormal values in lipid profiles. GC showed higher hs-CRP (2.1 ± 0.68 mg/L, p < 0.005) than GA: 0.56 ± 0.10 and GB: 0.44 ± 0.03 mg/L. HOMAIR presented DE of 83% and G/I of 82% to diagnose IR defined by OGTT. Conclusion: High frequency of IR was observed in PCOS adolescents including in 50% of patients with normal BMI. Insulin surrogate cutoffs used could efficiently demonstrate IR. The coexistence of IR and obesity substantially modifies metabolic and inflammatory profiles.