Síndrome Metabólica, seus fenótipos e resistência à insulina pelo HOMA-RI

Abstract

RESUMOO diagnóstico de síndrome metabólica (SM) segundo o National Cholesterol Education Program Adult Treatment Panel III não reflete necessariamente a presença de resistência à insulina (RI), um potencial alvo terapêutico para prevenção de diabetes tipo 2 e doenças cardiovasculares. Em estudo de corte transversal, assentado em dados anteriores de prevalência, avaliamos o comportamento do HOMA-RI, um parâmetro de RI bem difundido, frente à SM e anormalidades associadas. HOMA-RI foi maior nos indivíduos com SM (2,8 ± 1,6 vs. 1,8 ± 1,4) (p < 0,001) e mostrou excelente correlação com insulinemia de jejum (r S = 0,961). HOMA-RI ≥ 2,5 aliou bons níveis de especificidade e sensibilidade para a associação de SM e RI. Diferente de aumento da glicemia, obesidade abdominal e elevação da trigliceridemia, componentes da SM mais bem relacionados com RI, a elevação da pressão arterial e a redução do HDL-c não mostraram associação com HOMA-RI ≥ 2,5. A demonstração de que alguns fenótipos de SM ou anormalidades associadas foram mais preditivos de RI pode apontar para a possibilidade de uso do índice como um indicador de RI associada à SM. The diagnosis of the metabolic syndrome (MS) according to the National Cholesterol Education Program Adult Treatment Panel III does not reflect necessarily the presence of insulin resistance (IR), a potential therapeutical target for type 2 diabetes and cardiovascular disease prevention. Based on previous prevalence data, a cross-sectional study was conducted to determine the HOMA-IR relationship to the MS and some associated abnormalities. HOMA-IR was higher in individuals with the MS (2.8 ± 1.6 vs. 1.8 ± 1.4) (p < 0.001). HOMA-IR ≥ 2.5 allied good specificity and sensitivity levels for the association of MS and IR. Hyperglycemia, hypertrigliceridemia, and abdominal obesity, the MS components best related to IR, were statistically associated with HOMA-IR ≥ 2.5, but not hypertension neither low HDL-c. The demonstration that some of MS phenotypes or associated abnormalities were more predictive for IR could point out to the possibility of the use of the index as a marker of the presence of IR associated to MS.

Resistência insulínica e sua relação com os componentes da síndrome metabólica

“…The results of this study also show that the highest values of HOMA-IR were associated with the presence of greater numbers of MS components and that the mean values of each component increased as the percentile of HOMA-IR increased, a fact confirmed by Oliveira et al 36 , whose study showed that the HOMA-IR values increased from zero to five components of MS and with greater significance among individuals with two and three isolated components. This fact can be explained by the production and secretion of several factors that intensify with obesity, for instance, tumor necrosis factor α (TNF-α), resistin, plasminogen activator inhibitor 1 (PAI-1), Interleukin-6 and macrophage chemoattractant protein 1 (MCP-1), and are directly associated with insulin resistance induction, hypercoagulability and atherogenesis, which in turn cause hypertension and intensify the proinflammatory states, representing some of the criteria of MS and leading to an increased risk of cardiovascular and thromboembolic events 37 .…”

“…Moreover, the excess of circulating FFA, resulting from the lipotoxicity process, is a strong inducer of peripheral resistance to insulin action, increasing the likelihood of developing type 2 DM and MS 37 . The disclosure of an increasing frequency of MS as the HOMA-IR values increase, especially MS associated with components more specifically related to IR, may be pointing to the possibility of using the index as an indicator of the presence of IR associated with MS, which would favor the definition of the therapeutic approach and, consequently, the prognosis of affected individuals, more specifically nondiabetic ones 36 .…”

The Prevalence of Metabolic Syndrome in the Different Phenotypes of Polycystic Ovarian Syndrome

“…19 Metabolic disorders seem to be more prevalent in phenotypes A and B, that is, those considered as classic, followed by C (ovulatory), and much less frequently, D (nonhyperandogenic). 4,[20][21][22][23] The metabolic disorders presented in women with PCOS may make up metabolic syndrome (MetS), which is defined as the coexistence of risk factors for cardiovascular diseases in the same individual, with impaired glucose tolerance, dyslipidemia, and hypertension being the most relevant factors. Obesity, which is present in 30 to 70% of the cases of PCOS, presents an additive effect on metabolic risk factors, due to an exacerbation of insulin resistance (IR).…”

Sleepiness, inflammation and oxidative stress markers in middle-aged males with obstructive sleep apnea without metabolic syndrome: a cross-sectional study

“…Plasma glucose was determined using glucose oxidase calorimetric method. Insulin resistance was defined according to the Homeostasis Model Assessment-Insulin resistance (HOMA-IR) (fasting glucose [mg/dL] × fasting insulin [mU/mL]/405) > 2.7 [ 31 ]. Serum insulin was determined by radioimmunoassay.…”