Age-associated changes in physiological and biochemical arterial stiffness markers in apparently healthy individuals

Abstract

Objectives: Arterial stiffness occurs with increasing age and it is an independent cardiovascular risk factor. Brachial ankle pulse wave velocity (baPWV) and serum osteoprotegerin (OPG) are relatively new physiological and biochemical parameters to ascertain arterial stiffness. We determined age-associated changes in physiological and biochemical parameters of arterial stiffness. Materials and Methods: It was a cross-sectional, observational study conducted on apparently healthy 118 male and 114 female subjects of age group 30–>60 years without any cardiovascular or peripheral vascular disease or on any antihypertensive and lipid-lowering therapy. Brachial systolic blood pressure (bSBP), brachial diastolic blood pressure, central systolic blood pressure (cSBP), central diastolic blood pressure (cDBP), heart rate, augmentation index (AIx[%]) and baPWV were recorded after 10 min of rest. Mean arterial pressure (MAP), pulse pressure (PP) and PP ratio (PPR) were derived from the recorded data. Serum samples were analysed to estimate OPG level and lipid profile. Kruskal–Wallis test was performed to compare the differences of the parameters. Spearman correlation analysis was performed to determine any association between baPWV and other parameters. Multiple linear regression analysis was performed to determine the factors associated with baPWV. P < 0.05 was considered as statistically significant. Results: Males had significantly higher value of height, weight and PPR than females. Females had significantly higher values of BMI, AIx (%), cSBP, cPP and brachial PP than males. Aged males had significantly higher AIx (%), cPP and brachial PP in comparison to younger males. Aged females showed significantly higher AIx (%), cPP, brachial PP, serum cholesterol, triglyceride (TG), low-density lipoprotein cholesterol (LDLc) and very LDLc (VLDLc) in comparison to younger females. Serum OPG level was found to be a major factor influencing the values of baPWV in both males and females. Other cardiovascular parameters such as cSBP, cDBP, cMAP, brachial SBP and MAP influenced baPWV values in both genders, but biochemical parameters such as serum cholesterol, LDLc influenced baPWV values in the male participants in the present study. Regression analysis revealed that serum TG and OPG levels were strongly associated with baPWV in both genders. Conclusion: With increasing age, cardiovascular parameters such as central blood pressure, peripheral blood pressure and AIx (%) were increased in both genders, and PPR was decreased in males. The values of baPWV also exhibited an increasing trend with age. Serum cholesterol, TG, LDLc and VLDLc levels in females were increased with age. Serum OPG level and serum TG levels emerged as major influencing factors of baPWV values in both genders irrespective of age.