Sex Differences in Flexibility-Arterial Stiffness Relationship and Its Application for Diagnosis of Arterial Stiffening: A Cross-Sectional Observational Study

Abstract

PurposeArterial stiffness might be related to trunk flexibility in middle-aged and older participants, but it is also affected by age, sex, and blood pressure. This cross-sectional observational study investigated whether trunk flexibility is related to arterial stiffness after considering the major confounding factors of age, sex, and blood pressure. We further investigated whether a simple diagnostic test of flexibility could be helpful to screen for increased arterial stiffening.MethodsAccording to age and sex, we assigned 1150 adults (male, n = 536; female, n = 614; age, 18–89 y) to groups with either high- or poor-flexibility based on the sit-and-reach test. Arterial stiffness was assessed by cardio-ankle vascular index.ResultsIn all categories of men and in older women, arterial stiffness was higher in poor-flexibility than in high-flexibility (P<0.05). This difference remained significant after normalizing arterial stiffness for confounding factors such as blood pressure, but it was not found among young and middle-aged women. Stepwise multiple-regression analysis also supported the notion of the sex differences in flexibility-arterial stiffness relationship. Receiver operating characteristic curve analysis revealed that cut-off values for sit-and-reach among men and women were 33.2 (area under the curve [AUC], 0.711; 95% confidence interval [CI], 0.666–0.756; sensitivity, 61.7%; specificity, 69.7%) and 39.2 (AUC, 0.639; 95% CI, 0.592–0.686; sensitivity, 61.1%; specificity, 62.0%) cm, respectively.ConclusionOur results indicate that flexibility-arterial stiffness relationship is not affected by BP, which is a major confounding factor. In addition, sex differences are observed in this relationship; poor trunk flexibility increases arterial stiffness in young, middle-aged, and older men, whereas the relationship in women is found only in the elderly. Also, the sit-and-reach test can offer a simple method of predicting arterial stiffness at home or elsewhere.

Ingesting a small amount of beer reduces arterial stiffness in healthy humans

“…; Nishiwaki et al. ); a BP‐adjusted reduction in CAVI was also observed. In addition, no significant changes in BP and HR were observed 60 min after ingestion in either the B200 or the B350 trials, suggesting that these factors were not involved in the reductions of PWVs and CAVI, but rather, that these reductions truly reflect changes in arterial stiffness.…”

“…In our laboratory, coefficients of variation across observers' measurements, over ten subjects on two separate days (for reproducibility), were 7.5 ± 1.2%, 2.7 ± 0.3%, and 3.6 ± 0.6% for cfPWV, baPWV, and CAVI, respectively (Nishiwaki et al. , , ).…”

“…Carotid and femoral arterial pressure waveforms were recorded by amorphous pulse wave sensors (TY-501A; Fukuda Denshi) attached to the left common carotid and left common femoral arteries; values were automatically calculated as the distance between the carotid and femoral artery sites divided by the transit time. In our laboratory, coefficients of variation across observers' measurements, over ten subjects on two separate days (for reproducibility), were 7.5 AE 1.2%, 2.7 AE 0.3%, and 3.6 AE 0.6% for cfPWV, baPWV, and CAVI, respectively (Nishiwaki et al 2014(Nishiwaki et al , 2015(Nishiwaki et al , 2017.…”

“…HR, BP, and PWVs were measured using a semi‐automated device (VS‐1500AE/AN; Fukuda Denshi, Tokyo, Japan) with participants in supine position, as described in our previous studies (Nishiwaki et al. , , ). Cuffs to measure BP and PWV were wrapped around both brachial upper arms and ankles, and then brachial‐ankle PWV (baPWV) and cardio‐ankle vascular index (CAVI) were obtained as indexes of arterial stiffness.…”

“…According to a previous study (Hirayanagi et al 2006), circulating alcohol levels were also estimated using the following formula; circulating alcohol levels (%) = BAC (mg/L)/5. HR, BP, and PWVs were measured using a semi-automated device (VS-1500AE/AN; Fukuda Denshi, Tokyo, Japan) with participants in supine position, as described in our previous studies (Nishiwaki et al 2014(Nishiwaki et al , 2015(Nishiwaki et al , 2017. Cuffs to measure BP and PWV were wrapped around both brachial upper arms and ankles, and then brachial-ankle PWV (baPWV) and cardio-ankle vascular index (CAVI) were obtained as indexes of arterial stiffness.…”