Global Health Asia-Pacific March 2020 | Page 31

Normal resting heart rate varies widely from person to person Analysis of massive data from wearable devices compared heart beats A person’s normal resting heart rate is fairly consistent over time but may vary from others’ by a considerable number of beats per minute, according to the biggest analysis of heart beats ever carried out. A team from the Scripps Research Translational Institute in California set out to analyse data from wearable devices such as smart watches that tracked the heart rates of over 92,000 people from across the United States. The team used nearly 33 million days’ worth of data to examine variations in resting heart rate for individuals over time. The analysis showed that one person’s mean daily resting heart rate may differ by up to 70 beats per minute from another person’s normal rate. A routine visit to the doctor usually involves a measurement of resting heart rate, but such measurements are rarely actionable unless they deviate significantly from a “normal” range established by population-level studies. However, wearables that track heart rate now provide the opportunity to continuously monitor heart rate over time and identify normal resting heart rates at the individual level. “Day-to-day changes in resting heart rate could be the first true, individualised ‘digital vital sign’ [which is] now possible to measure thanks to wearable sensor technologies,” the authors wrote in the journal Plos One. “These variations in resting heart rate may allow for the identification of early unexpected changes in an individuals’ health.” GlobalHealthAndTravel.com Statins are no replacement for exercise and a healthy lifestyle Patients on preventative medication feel they have a ‘free pass” to be unhealthy P atients who use lipid-lowering or antihypertensive medication, like statins, are more likely to gain weight and be less physically active than those who don’t, according to a sizeable analysis of patients in Finland. The findings raise concern about the so-called “substitution” hypothesis where patients may view that the perceived effectiveness of a medication gives them a free pass when it comes to important lifestyle changes needed for the prevention of cardiovascular disease, researchers said in the Journal of the American Heart Association. Previous studies have suggested that physical activity is lower among statin users and those taking blood pressure-lowering medication, though data from the early 2000s showed these patients consumed fewer calories and less saturated fat than nonusers. Those trends were reversed in later surveys, however. Also, previous cross-sectional studies tended to be small, with a lack of data testing the substitution hypothesis, as well as a lack of data in primary prevention patients. The new study now raises questions about how doctors monitor lifestyle changes while treating patients using preventative medication. “Few studies have examined whether initiation of preventive medication affects lifestyle, either increasing or decreasing the likelihood of unhealthy behaviours. Because initiation of antihypertensive or statin therapy appears to be associated with some negative lifestyle changes, expansion of pharmacologic interventions toward populations at low cardiovascular disease risk may not necessarily lead to expected benefits at the population level, the researchers concluded. “Effective measures are needed to support the recommended lifestyle change in relation to the initiation of pharmacologic interventions for primary prevention.” MARCH 2020 29