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Purpose: Previous studies on the impact on arterial health of contraceptive use, or across the menstrual phases, have yielded differing results. Furthermore, there is little research on the differences based on the delivery method of the contraceptive, oral vs parenteral contraceptives. In this study, we examined arterial health using three different physiological measures of arterial function and structure in contraceptive users and non-users.

Methods: Young, healthy women, between 18.0–25.9 years of age were enrolled in the study (n = 577). Menstrual phase and contraceptive use and type were assessed by questionnaire. Arterial stiffness was measured using pulse-wave velocity (PWV) and augmentation index (AIx). Arterial thickness was measured using carotid-intima media thickness (cIMT). Blood samples were analysed for various biomarkers, which were used in multivariate regressions to adjust for the effects of contraceptive use on vascular status.

Results: Contraceptive users had a higher PWV than non-users. The menstrual phase did not impact PWV. In a smaller subgroup analysis, comparing the types of contraceptives, oral or parenteral, did not impact PWV. AIx and cIMT did not differ significantly between any studied groups. Systolic blood pressure, BMI, serum lipids, C-reactive protein, and sex hormone binding globulin concentrations were higher in the contraceptive using group, but in multivariable models, these biomarkers had only limited impact on the association between contraceptive use and PWV.

Conclusion: In a population of young, healthy women, contraceptive users displayed higher PWV values. The effect could not be explained by the effect of contraceptives on androgenicity, blood pressure or lipids.

Background: Handgrip strength (HGS) is a surrogate marker of whole body strength that has been observed to correlate inversely with the metabolic syndrome (MetS). In this study, we examined whether HGS in young, healthy individuals, was associated with surrogate endpoints of the MetS. A secondary goal was to examine whether absolute HGS (absHGS) or relative HGS (relHGS) was a stronger predictor of MetS.

Method: 834 subjects (577 women), aged 18–26, were recruited. Surrogate endpoints for MetS were waist circumference, HDL, fasting glucose, fasting insulin, triglycerides, and systolic and diastolic blood pressure (BP). We also examined the association between HGS and body fat percentage, HOMA-IR, CRP, orosomucoid and apolipoprotein A-1 and apolipoprotein B. The associations were examined using multivariable linear regression.

Results: AbsHGS and relHGS were each associated with several surrogate endpoints of the metabolic syndrome, with RelHGS being statistically significantly associated with a greater number of the variables – all except fasting glucose and diastolic BP.

Conclusion: RelHGS correlates with components of the MetS even in young, healthy populations. It is a better predictor of MetS components than absHGS. As a cheap and easy to use biomarker, relHGS holds merit as a screening tool for metabolic dysfunction even in preclinical contexts.

Objectives: Handgrip strength (HGS) is a surrogate marker of general risk and nutritional status, frequently used in clinical practice. This study aimed to determine clinically useful reference intervals for healthy, young adults from Northern Europe.

Methods: This cross-sectional study was conducted in central Sweden, recruiting 834 young, nonsmoking adults ages 18 to 26 y. Subjects responded to a questionnaire on general health status, medication (including contraceptives), exercise habits, and parental and their own country of birth. Anthropometry, bioimpedance analysis for determination of fat-free mass (FFM), and HGS was measured. Reference intervals were calculated as mean and standard deviation. Differences between men, women, and women using estrogen contraceptives were analyzed using an analysis of variance with Tukey's post hoc test. Associations between HGS and determinant variables were analyzed using Spearman and linear regressions.

Results: Men and women differed in HGS, but no significant difference was found in average HGS based on contraceptive use in women. Mean HGS was 53 kg in men and 34 kg in women, with a range of 22 kg to 90 kg in men and 16 kg to 73 kg in women. Height correlated with HGS. Subjects with a body mass index (BMI) <20 had statistically significantly lower HGS than those in higher BMI groups. There was no statistically significant mean difference between the group of subjects with a BMI of 20 to 25 and those with BMI >25 in neither men nor women. HGS in both sexes showed a gradual increase through tertiles of FFM. In linear regression models, sex, height, and FFM were the main determinants of HGS.

Conclusions: In this study, we established reference intervals for HGS in healthy Swedish adults ages 18 to 26 y. As a surrogate marker of whole-body muscle mass, these reference intervals can be used in health assessments and the planning of health-promoting measures in the individual young adults. Differences in HGS based on height warrant height-specific reference intervals that should be established locally.

Background and aims: In healthy, young adults we analyzed a panel of cardiovascular disease related proteins in plasma and compared them with the vascular health of the subjects. The aim was to identify proteins with a relationship to the early atherosclerotic process in healthy individuals.

Methods: We employed the proximity extension assay from OLINK proteomics to analyze 92 cardiovascular disease (CVD) related proteins on 833 subjects (men and women, ages 18–26). The women were further divided into an estrogen-using group and non-users. Protein expression was analyzed using principal component analysis (PCA). The following vascular examinations were performed: Pulse-wave velocity (PWV), augmentation index (AIX), carotid-intima media thickness (cIMT).

Results: Three principal components were obtained using PCA to analyze the protein expression. None of the obtained principal components correlated significantly with AIX or cIMT. One of the components, explaining 6% of the total variance of the data, was significantly correlated with PWV. Upon examination of the proteins with the highest factor loadings on this component independently in a multivariable model, adjusting for established CVD risk biomarkers, insulin-like growth factor-binding protein 1 (IGFBP-1) and insulin-like growth factor-binding protein 2 (IGFBP-2) were found to independently, negatively correlate with PWV. Among the established risk factors included in the multivariable model, age was significantly and adversely correlated with all vascular measurements.

Conclusions: In this population of healthy, young adults, groups of CVD related proteins correlate with PWV, but not AIX or cIMT. This group of proteins, of which IGFBP-1 and IGFBP-2 were independently, negatively correlated in a multivariable model with PWV, could have benificial effects on vascular stiffness. The robust association between age and PWV, AIX and cIMT provide insight into the impact of aging on the vasculature, which is detectable even in a population of young, healthy, non-smoking individuals of ages spanning only 8 years.

Background and aims: We aimed to identify plasma protein biomarkers related to inflammation that correlated with physiological measurements of vascular function and structure in healthy individuals.

Methods: We used the OLINK proteomics panel, which measures 92 inflammatory proteins, in 834 young, healthy non-smokers (ages 18-26). Principal component analysis (PCA) was employed to identify patterns of proteins. The following measurements were used: pulse-wave velocity (PWV), carotid intima-media thickness (cIMT) and augmentation index (AIX). Established cardiovascular risk factors were included in multivariable models.

Results: PCA showed four principal components (PC 1, PC 2, PC 3, PC 4). PC 3, comprising proteins related to hemostasis, was significantly and inversely correlated with PWV. Among the proteins with the highest factor loadings on PC 3, uPA was negatively correlated with PWV in multivariable regression models. AIX was significantly correlated with PC 2, comprising inflammatory cytokines. Among the proteins with the highest factor loadings on PC 2, interleukin-6 was significantly correlated with AIX in the multivariable model. cIMT was significantly correlated with PC 4, comprising proteins related to chemotaxis. Among the proteins with the highest factor loadings on PC 4, fractalkine was significantly correlated with cIMT in the multivariable model.

Conclusions: In young, healthy individuals, OLINK inflammatory proteins correlated with measures of vascular status. Each of the three measures PWV, AIX, and cIMT, which target different parts of the vasculature, correlated with its own specific protein signature, indicating that different subsets of inflammatory mediators affect different parts of the vasculature and are detectable already in young healthy adults.

The primary aim was to appraise the relationship between body fat percentage and the inflammatory markers C-reactive protein (CRP) and orosomucoid in a population of young, non-smoking, healthy, Swedish adults, without any chronic diseases. A secondary aim was to compare whether these associations differed between the women using estrogen contraceptives and those who did not. We assessed the association in linear regression models between body fat percentage based on a bio-impedance measurement and plasma concentrations of CRP and orosomucoid in men and women aged 18-26 years, n = 834. Statistically significant associations were found between body fat percentage and both biomarkers of inflammation, with beta coefficients of 0.30 (95% CI 0.24-0.37) and 0.28 (0.22-0.35) for CRP and orosomucoid, respectively (p < .001). Adjustment for established risk factors marginally lowered the effects sizes (partial betas, 0.28 and 0.20, respectively), while the strong statistically significant associations remained. In the female cohort, estrogen and non-estrogen using subpopulations did not significantly differ in the correlations between body fat percentage and the inflammatory biomarkers, even adjusted for established cardiometabolic risk factors. In conclusion, in healthy young adults, higher levels of body fat percentage are associated with elevations in plasma biomarkers of inflammation, suggesting that a systemic inflammatory process, promoting atherosclerosis, may commence already at this early stage in life. CRP and orosomucoid plasma concentrations differed between users and non-users of estrogen contraceptives, but both subgroups showed similar correlations between increasing body fat percentage and increasing plasma concentrations of the biomarkers of inflammation.