Some efforts have been made to find the determinants of AS in patients with MS beyond PWV. A body shape index (ABSI) calculated from waist circumference, BMI, and body height has been confirmed to identify people with MS and increased AS [
93]. Nedogoda et al. have documented carotid–femoral PWV to be a better parameter for early vascular aging estimation in patients with MS in comparison to clinical scales, Systematic COronary Risk Evaluation (SCORE) scale, QRESEARCH cardiovascular risk algorithm (QRISK-3) scale, and Framingham scale [
94].
Patients diagnosed with arterial hypertension have a high prevalence of metabolic syndrome regardless of controlled or resistant hypertension [
95]. Hypertensive patients with MS were shown to be older (57.9 ± 12.2 vs. 52.7 ± 14.1 years,
p < 0.001) and to have higher PWV (9.0 ± 2.3 vs. 8.4 ± 2.1 m/s,
p = 0.001) than those without MS [
96]. Predicting the risk of cardiovascular events in MS patients is crucial. In a prospective study involving 2728 middle-aged patients with MS, the occurrence of at least one cardiovascular event was associated with higher mean BP, aortic PWV, aortic augmentation index, and carotid intima-media thickness (
p < 0.05 for all variables) [
97].
4. Importance of Analyzed Research in Routine Clinical Practice
MS, as a group of metabolic disorders, is strongly associated with subclinical vascular damage, marked by increased PWV value [99,100]. As proved in the cited literature as well as a study performed by Gagliardino, PWV is significantly impaired in patients with complete pictures of MS. Furthermore, the level of PWV is significantly increasing with the increasing number of MS components, supporting the need for careful research for the early diagnosis of CVD in patients with MS as a cost-effective preventive strategy [101,102]. Moreover, higher glucose levels in the prediabetic range and IR might lead to higher AS and concentric remodeling of the heart muscle [103].
Abdominal obesity is an important component of MS. The ambulatory AS index of the obese subjects is significantly higher than in the healthy controls [
104,
105,
106]. Moreover, sensitivity analyses demonstrated that higher PWV is associated with waist circumference-to-BMI ratio and it remains significant after adjustment for HR, metabolic risk factors, and inflammatory markers [
107,
108]. It is crucial for obese patients who have lost weight to maintain their status, as weight regaining worsens AS with a significant increase in PWV, especially in patients with obesity and MS [
56]. Moreover, it is important to pay particular attention to patients with MS and AS in whom the adverse effect of metabolic disturbances on arterial function can be offset by an adequate program of exercises, which includes mainly aerobic physical training [
109,
110].
It is important to measure PWV under stabilized BP and HR values, particularly in patients with newly diagnosed hypertension in whom detection of organ damage mediated by asymptomatic hypertension has an impact on risk stratification [
111,
112]. PWV is positively correlated with both SBP and DBP [
113]. An increase in PWV is associated with a significantly higher risk of hypertension incidence [
114]. However, treatment of MS components is guided by its component level and clinical vascular damage. There are no guidelines for the treatment of subclinical vascular damage based on and guided by PWV. Chronic renin-angiotensin blockade (olmesartan) has been documented to lower AS partly independently of the corresponding reduction in BP [
115]. The strategy to prevent cardiovascular and renal events based on AS (SPARTE Study) has been shown to reduce office and ambulatory SBP and DBP, and prevent vascular aging, but not to reduce cardiovascular outcomes despite the higher intensity of treatment when there was PWV normalization-driven strategy treatment compared to BP-driven strategy [
116]. However, as the study authors underline, it was the first study to focus on the impact of AS on cardiovascular outcomes. Furthermore, the main limitation of the study was the small number of patients and its limited capacity for clinical events.
The risk of increased AS depends on hyperlipidemia at young ages [
117]. Dyslipidemia therapy guidelines are focused mainly on LDL-C lowering when considering cardiovascular outcomes. However, as shown in studies cited before, the TG/HDL-C index was shown to be positively correlated with PWV and could be considered an independent risk factor for the development of AS. Thus, even after reaching the recommended levels of LDL-C, there are still lipid disorders that may increase residual cardiovascular risk [
118]. AIP demonstrates the relationship between atherogenic and preventive lipoproteins. The link between PWV and AIP supports the view that the calculation of AIP should be included in the everyday clinical evaluation of the risk of cardiovascular disease, especially due to the easy calculation of AIP from routine lipid profiles. It could be an effective predictive value to detect early vascular aging and subclinical atherosclerosis [
119,
120].
5. Conclusions
MS and its components are a significant problem for healthcare systems worldwide. CVD is the leading cause of morbidity and mortality, and, on the other hand, MS predisposes the development of CVD. The identification of patients with features of subclinical dysfunction of the cardiovascular system in the population of patients with MS and its components is also very important in clinical practice, and PWV measurement is a valuable tool for this purpose.
AS defined by PWV is positively correlated with both SBP and DBP. It may indicate subclinical organ damage in patients with hypertension. In addition, the decrease in PWV level during hypertensive therapy can identify a group of patients with better outcomes independently from BP reduction.
Obese patients with MS who have lost and regained weight are predisposed to have a significant increase in PWV, above their baseline levels. The adverse effect of metabolic disturbances on arterial function can be offset by an adequate program of exercises, which includes mainly aerobic physical training.
The TG/HDL-C ratio demonstrates the ratio between the atherogenic and preventive lipoproteins. The increased TG/HDL-C levels ratio is positively correlated with increased PWV levels and is an independent risk factor for cardiometabolic disease, with a consecutive correlation that was not proved separately for TG and HDL-C levels.
IR affects AS and accelerates arterial aging. Non-insulin-based IR index, such as METS-IR, can predict arterial stiffens due to a strong positive correlation with PWV.