Lowering exposure to air pollutants by using face masks may help patients with coronary heart disease (CHD) experience less symptoms, Chinese researchers say. A study in Beijin, one of the world's most polluted cities, has demonstrated that heart disease symptoms and blood pressure were both reduced when older men and women with CHD wore face masks while walking in the city. During the trial carried out by researchers of Peking University and University of Edinburgh, UK, the 92 participants walked for two hours in two different spring days while wearing a mask in one and walking unprotected during the other day. The participants were given high-efficiency face masks which protected them from fine and ultrafine particulate matters (PM). After each session, the researchers measured each person's blood pressure, heart rate variability (HRV) and faulty heart beats - called arrhythmia and also asked about symptoms they experienced such as tiredness, nausea and headaches. The results showed when CHD patients used high-efficiency masks on average their blood pressure was significantly lower and heart rate variability (HRV) was higher, both indicating improved cardiovascular health. The participants also found the face masks comfortable and reported that pollution-related symptoms were lower when they walked wearing the mask. “Reducing personal exposure to PM air pollution was associated with small but consistent improvements in objective measures of myocardial ischemia, exercise-related increases in blood pressure, and heart rate variability in patients with coronary heart disease," the authors concluded in their report published in Environmental Health Perspectives. “Although efforts to reduce emissions are critical to reducing exposures to the population as a whole, use of a face mask may be an effective individual-level intervention for high-risk populations. The use of a face mask has the potential to reduce the incidence of acute cardiovascular events, as well as improving patients' general well-being, particularly in developing countries where pollutant exposures are high and resources to reduce emissions are limited."
