Age-dependent aspects of informativeness of surrogate indices of insulin resistance in the formation of menopausal metabolic syndrome
L.A. Ruyatkina, D.S. Ruyatkin, L.V. Shcherbakova
1) Novosibirsk State Medical University, Novosibirsk, Russia;
2) Research Institute of Therapy and Preventive Medicine - Branch Campus of the Federal Research Center, Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Background. The need to assess insulin resistance (IR), which pathogenetically combines the components of the metabolic syndrome (MS), is of particular importance during its formation during the menopausal transition due to changes in the functional state of the pituitary–ovarian axis. In addition to the traditional indices of the HOMA family, the TyG index has attracted attention in recent years as surrogate indicator, showing close agreement with the clamp test, the gold standard for assessing the severity of IR. However, comparative studies of the informativity of surrogate insulin and non-insulin indices in the perimenopausal period are practically absent.
Objective. Evaluation of the effect of age on the relationship of surrogate indices of IR, TyG, and the HOMA2 family with the parameters of menopausal MS during its formation in a cohort of women aged 35–59 years without dysglycemia, depending on the presence of arterial hypertension (AH).
Methods. Body mass index (BMI), waist circumference (WC), blood pressure, triglycerides, HDL-C, IRI, FSH and estradiol levels, fasting glycemia, TyG and HOMA2 family indices were determined in 88 normoglycemic women aged 35–59 years with different functional state of the pituitary-ovarian axis and divided into 2 groups depending on the presence of arterial hypertension. Using SPSS (version 17), ME (25–75%); intergroup differences according to the Mann-Whitney test assessed; Spearman rank correlation analysis and partial correlation analysis to level the influence of age were carried out.
Results. The largest range of significant associations, independent of age and in tandem with it, in contrast to the HOMA2 family indices, was found in TyG in the group of patients with arterial hypertension: with WC and BMI, IRI and HDL-C, FSH and E2. The TyG index is also influenced by age-associated factors: the duration of arterial hypertension and postmenopause. In the general cohort of women (n=88), most of these correlations persist and increase, but associations with FSH and E2 persist only within the Spearman analysis. Stable associations of TyG with IRI in the absence of those with HOMA2-B in patients with hypertension without dysglycemia attract attention.
Conclusion. In the process of the formation of menopausal MS in patients with AH, the TyG index, in contrast to HOMA2-IR and HOMA2-S, forms a greater number of stable age-associated an age-independent correlations with MS markers and indicators of the functional activity of the pituitary-ovarian axis during the period of menopausal transition. Correlations of TyG with RI levels, which are stable when the effect of age is leveled in patients with AH without dysglycemia, indicate the threat of carbohydrate metabolism disorders through the phenomenon of lipoglucotoxicity with a further increase in RI against the background of estrogen deficiency.
About the Autors
Corresponding author: Lyudmila A. Ruyatkina, Dr. Sci. (Med.), Professor, Novosibirsk State Medical University, Novosibirsk, Russia; email@example.com