CHANGES IN BLOOD PRESSURE OVER A 6-YEARS PERIOD IN THE POPULATION-BASED SWISS LONGITUDINAL COHORT STUDY (SWICOS)

Objective: Previous studies reported an increase in the burden of cardiovascular risk factors in developed countries over the years. In particular, an increasing prevalence of obesity is a cause of concern. Therefore, we analyzed changes in blood pressure (BP) and other cardiovascular risk factors in the population-based Swiss Longitudinal Cohort (SWICOS) over a 6-years period. Design and method: This analysis comprised 366 SWICOS participants who underwent follow-up 6 years after the initial baseline examination until October 31, 2024. BP values, other cardiovascular risk factors and other potentially influential variables, such as obesity, were descriptively compared between baseline and follow-up examination. BP and body composition were measured with validated devices. Results: Of the 366 SWICOS participants, 158 (43.2%) were males and 208 (56.8%) females. The mean follow-up duration was 6.56±0.6 years, and mean age of the participants significantly (p<0.001) increased by the same amount. The prevalence of obesity, defined as body mass index >30 kg/m2, significantly (p<0.001) increased from 13.2% at baseline to 17.9% at follow-up. This was also reflected by the significant (p<0.001) increase of mean relative body fat mass from 26.9±0.3% to28.6±7.9%. The median time spent watching television increased from 420 to 540 minutes per week (p<0.001), at the same time mean relative body muscle mass decreased significantly (p<0.001) from 69.1±8.5% to 51.7±10.8%. This decrease in muscle mass was also reflected by less force (e.g., decrease of measured handgrip strength from 35.9±12.2 kg to 33.2±12.3 kg, p<0.001). At the same time, mean systolic BP remained unchanged (133.5±18.6mmHg at baseline vs. 132.2±17.8mmHg at follow-up, p=0.091), whereas mean diastolic BP significantly increased from 80.9±9.6mmHg at baseline to 83.6±10.3mmHg at follow-up (p<0.001). LDL non-significantly decreased from 3.4±1.0mmol/l to 3.3±1.0mmol/l (p=0.063). Conclusions: This analysis suggests that despite an ageing population with increasing weight and increasingly sedentary lifestyle, it was possible to keep BP and LDL values in the same range over a 6-years period in a country with unlimited access to healthcare.