Activity Monitoring and the Effects of the Environment on Blood Pressure

Abstract

In this chapter, I focused on variables that influence cardiovascular variability, particularly blood pressure (BP) and heart rate. These include physical activity, temperature, noise, and atmospheric particulate matter. Chronic physical activity such as exercise has an important effect to reduce cardiovascular complications. Day-to-day activity measured using actigraphy is an important factor in short-term changes in BP and heart rate and in defining sleep versus awake periods for the analysis of 24-h ambulatory BP monitoring. Indeed, actigraphy has become a mass marketed consumer gadget that may allow individuals to monitor their own daily levels of activity. Other novel uses of actigraphy include supplementing polysomnography for sleep studies and also in a variety of neurological or other disorders. There seems little doubt that colder temperatures are associated with higher BP and heart rate. What is needed is a better understanding of whether the effects are due to temperature alone or due to other factors that change during the seasons. Environmental noise has been given full attention as an important factor in cardiovascular risk. Potential mechanisms are being elucidated that are known to link to worse cardiovascular outcomes. Regulations should be able to keep exposure below critical thresholds. Lastly, the effects of air pollution and, in particular, fine particulate matter are now well-recognized by many cardiovascular groups as being adverse on cardiovascular disease. Studies suggest that there is a direct effect of fine particulate matter to raise BP and also to increase sympathetic nervous system activity. It is likely that further refinements will be made to these factors influencing blood pressure variability.