People who are exposed to high pollution levels are at significantly higher risk of suffering from hypertension, metabolic syndrome and heart diseases, says a new study.In the study, published in Journal of Public Health, the researchers investigated the associations between a long-term exposure to ambient air pollution and residential distance to green spaces and major roads with the development of hypertension and metabolic syndrome components such as a high triglyceride level, reduced high-density lipoprotein cholesterol, higher blood glucose, and obesity.Hypertension and metabolic syndrome are important causes of cardiovascular diseases, the researchers said.The study's findings showed that air pollution levels above the median are associated with a higher risk of reduced high density lipoprotein. Traffic-related exposure was associated with the incidence of hypertension, higher triglyceride level and reduced high-density lipoprotein cholesterol. However, the negative impact of traffic air pollutants was observed only in the participants who lived in multifamily buildings.The researchers also found positive effects of the natural environment, and have emphasized the positive impact of such spaces on cardiovascular health."Our research results enable us to say that we should regulate as much as possible the living space for one person in multifamily houses, improve the noise insulation of apartments, and promote the development of green spaces in multifamily houses" said study's lead author Agn Brazien.