A common class of blood pressure medicines known as angiotensin converting enzyme (ACE) inhibitors has long been known to be a cause of chronic coughing in some patients. It turns out that the enhanced cough reflex due to these medicines may decrease the risk of developing pneumonia.
In this week’s edition of the British Medical Journal, researchers combined 37 previously published randomized clinical trials and found that pneumonia risk was reduced by 34% in those taking ACE inhibitors. The effect was more dramatic in those with prior stroke with a 54% reduction in the risk of developing pneumonia. Asian patients had a more dramatic decrease in pneumonia risk compared to non-Asians. ACE inhibitors also decreased the risk of dying from pneumonia.
In 2010, pneumonia was the 9th most common cause of death in adults. Those over the age of 65 years, a population with a high incidence of hypertension, are even more likely to die from pneumonia than younger adults. Other risk factors for pneumonia include prior stroke, smoking, chronic lung disease, heart failure, diabetes, chronic kidney disease, and alcohol dependency.
ACE inhibitors are commonly used in patients with heart disease and prior stroke. This class of medicines sensitizes the sensory nerves of the airway and enhances the cough reflex which may protect and clear the airway from respiratory secretions and bacteria causing pneumonia. These medicines also improve swallowing and help the airway to avoid exposure to secretions from the throat and mouth. This may be especially important in stroke patients who sometimes have damage to their swallowing mechanism.