How does haemodynamics change over the period 17 to 25? The impact of obesity and smoking

Abstract

Abstract Aim: To investigate the aortic hemodynamic changes and its association to risk factors-smoking and obesity between 17-24 years using a novel aortic pressure waveform approach. Background: To understand the vascular ageing process, we need to investigate age-related changes earlier in the life-course. The American Heart Association (AHA) has outlined seven modifiable risk factors - the healthy diet, obesity evasion nonsmoking, total cholesterol check, physical activity, blood pressure and fasting glucose levels. If these risk factors are not kept at ideal levels they will contribute to early vascular ageing (EVA). This research investigates the changes in the CVS, as assessed by central haemodynamics, from adolescence to emerging adulthood and how these changes relate to two key risk factors: obesity and smoking. Methodology: Data is from the ALSPAC (Avon Longitudinal Study of Parents and Children) prospective population-based birth cohort. 814 participants (329 male), attended repeated clinical investigations aged 17 and 24yrs. Key haemodynamic outcomes were derived from radial pressure waveforms via applanation tonometry using the SphygmoCor® device (SPT-304), body measurements were measured (height, weight) and lifestyle patterns (habits, nature of work) are collected via a questionnaire. The change in variables from 17-24yrs was assessed using t-tests. Linear regression was applied to assess each key exposure affects the key haemodynamic outcomes at both ages. Linear mixed models were used to investigate age modifications. The data was analyzed using Software for Statistics and Data Science (STATA) package version15. Results: There were 59.58% (n= 485) females and 40.41% (n= 329) males, out of total (n= 814) participants. All the mean values were significantly (p<0.05) higher among males than females, except TFM and BMI. Females were more likely to smoke, drink excessively, and be obese at both the ages (i.e. 17 and 24 years) compared to males, who were more likely to be unemployed. A significant inverse association was observed between smoking status (never vs current) and SBP, DBP, MAP, CMP, CSP at 24 years of age. Significant associations (both direct and inverse) were observed between obesity and all the studied measures, except FEW and PP. Conclusion: The substantial central haemodynamics changes like a rise in central BP followed by a decline in peripheral BP takes place between 17 to 24 years. Therefore, the application of applanation tonometry, a non-invasive, sophisticated, pathophysiologically appropriate technique has been deployed over conventional invasive peripheral BP monitoring methods. The aorta ages rapidly over other small vessels and thus prevalent vascular changes are pragmatic.

Keywords: Pulse Wave velocity, haemodynamics, cardiovascular, peripheral resistance, smoking, obesity, arterial pressure