Patients hospitalised because of pneumonia are at less risk of dying from the disease if they have been taking the widely used cholesterol-lowering drugs 'statins' before hospital admission.
These results, published in the Open Access journal Respiratory Research, suggest another beneficial use of statins, which are prescribed to an increasing number of patients to prevent and treat high cholesterol, diabetes, heart disease and vascular disease.
Pneumonia is the seventh most common cause of death and the leading cause of death from infection in the USA, where it kills up to 40,000 people every year – those most at risk are very young children, elderly people and patients with underlying health problems such as AIDS or chronic obstructive pulmonary disease (CPOD). The disease is caused by viruses or bacteria, which are becoming resistant to the antibiotics used to treat bacterial pneumonia.
Eric Mortensen and colleagues, from the University of Texas Health Centre at San Antonio measured the risk of dying from pneumonia in patients admitted with pneumonia who were taking statins prior to their entry into hospital. They compared it with the risk of dying from the disease in pneumonia patients who were not taking statins. The authors used the Pneumonia Severity Index to rate the risk of dying within 30 days of admission to hospital in the two groups of patients. The results of their statistical analysis show that patients who were on a statin when they entered hospital were 2.8 times less likely to die than patients who were not on statins.
"Prior outpatient statin use was associated with decreased mortality in patients hospitalized with community-acquired pneumonia despite their use being associated with comorbid illnesses likely to contribute to increased mortality", write the authors.
More research is needed to explain the protective effect of statins on patients suffering from pneumonia. Statins act on the cholesterol-regulating enzyme HMG-CoA reductase, but they are also known to affect the immune system and this might explain their effect on pneumonia patients.