The increased risk for COVID-19 pneumonia in people who smoke cigarettes or have chronic obstructive pulmonary disease (COPD) may be at least partly explained by increased levels of an enzyme that enables the virus to more easily enter their lungs, according to a research letter published today in the European Respiratory Journal. Mary Van Beusekom writes in CIDRAP that in the same journal, a study has identified advanced age, underlying cardiovascular or cerebrovascular illnesses, low levels of CD3⁺CD8⁺ T cells (indicating damaged immune response), and high levels of cardiac troponin (indicating heart damage) as predictors of death in patients with COVID-19 pneumonia.