Background
Insulin resistance is associated with the development of hypertension, whereas there were rare studies comparing various non-insulin based insulin resistance (NI-IR) indices for the possibility of hypertension among young and middle-aged adults.
Methods
This cross-sectional study included a total of 4,080 military personnel, aged 18–50 years, without antihypertensive medications therapy in 2014. All subjects received annual health examinations for blood pressure (BP) measurements. Stage I isolated diastolic hypertension (IDH) and isolated systolic hypertension (ISH) and combined hypertension were respectively defined as systolic BP (SBP) < 130 mmHg/diastolic BP (DBP) 80–89 mmHg, SBP 130–139 mmHg/DBP < 80 mmHg, and SBP 130–139 mmHg/DBP 80–89 mmHg. The cut-off values of stage II hypertension for SBP and DBP were 140–159 mmHg and 90–99 mmHg, respectively. Four NI-IR indices included the serum triglycerides (TG) to high-density lipoprotein cholesterol (HDL-C) ratio, TyG index, Metabolic Score for IR (METS-IR) and ZJU index which were defined according to their specific formula. Multiple logistic regression analysis with adjustments for age, sex, anthropometrics, substance use, kidney function, serum uric acid, atherogenic cholesterols and physical activity was performed to determine the associations.
Results
There were 1,024 subjects with hypertension (25.1%) in which 739 were stage I hypertension, and 285 were stage II hypertension. For total hypertension, there were an association with TyG and METS-IR indices [odds ratios (ORs) and 95% confidence intervals: 1.432 (1.215–1.688) and 1.553 (1.040–2.321), respectively]. For hypertension subtypes, TyG index was positively associated with overall, stage I, and stage II ISH [ORs: 1.447 (1.149–1.823), 1.317 (1.029–1.687), and 2.011 (1.351–2.994), respectively], while TG/HDL-C, METS-IR and ZJU indices were merely associated with stage II ISH [ORs: 1.053 (1.006–1.103), 3.001 (1.171–7.696) and 1.009 (1.000-1.017), respectively]. In addition, TyG and METS-IR indices were positively associated with stage II IDH [ORs: 1.813 (1.207–2.721) and 2.85 (1.080–7.520), respectively], and TyG index was also associated with combined hypertension [OR: 1.425 (1.007–1.833)].
Conclusion
Among young and middle-aged adults, insulin resistance assessed by the four NI-IR indices was positively associated with stage II ISH, while only TyG index had a significant association for both stage II IDH and combined hypertension.