According to the American Lung Association, asthma affects 25.2 million people, including 6.2 million children, and accounts for millions of emergency department visits. In recent years, however, there have been significant improvements.
“The first major advance in the management of asthma came when we accepted that this was not just a disease of smooth muscles, but a chronic inflammatory condition that required drugs that relaxed the smooth muscles – like albuterol – but also anti-inflammatory medications like inhaled steroids,” says Mark Rolfe, a lung transplant and critical care pulmonologist at INTEGRIS in Oklahoma City. “In the last decade, more and more emphasis has been placed on blocking the cells that release inflammatory mediators or the production of these mediators with drugs like leukotriene inhibitors and biologicals.”
Despite this progress, Rolfe says approximately 10 Americans die every day from asthma – often from medical non-compliance or inadequate treatment.
Chronic obstructive pulmonary disease (COPD) is the third leading cause of disease-related death in the United States, according to reports from the Centers for Disease Control and Prevention.
“COPD is a generic term for anything that causes airflow obstruction,” says Rolfe, which includes both under-treated asthma with airway scarring and chemical induced airway inflammation, which occurs through smoking.
Rolfe says in chemical induced COPD, you have emphysema at one end of the spectrum, in which the alveoli (gas exchange sacks in the lung) are primarily damaged, and at the other end is chronic bronchitis, in which airways are predominantly effected with variable airway narrowing, chronic mucous gland hypersecretion and chronic sputum production … and in severe cases, low oxygen levels and high carbon dioxide levels.
“Most people fall somewhere on this line with more or less emphysema or bronchitis combined,” says Rolfe.
Usual Interstitial Pneumonitis
“The most devastating lung disease of the older population –50 plus – is a disease call usual interstitial pneumonitis,” says Rolfe. “It is a progressive scarring of the lungs that results in low oxygen and, eventually, high CO2 levels with pulmonary hypertension, resulting in the right side of the heart failing and eventual death.”
He says there are currently two medications that can slow the rate of this scarring, but neither can cure the disease, so a lung transplant becomes the only option for treatment.
its Effect on the Lungs
“COVID-19 attaches to receptors in the lungs that are normally there for chemicals that the body makes naturally, called angiotensin receptors,” says Rolfe. “They use this doorway to enter the cells, take over the genetics of the cell to replicate itself, and then kill the cell.”
He says it’s a systemic disease that activates multiple inflammatory pathways resulting in blood clotting, low blood pressure, renal failure and even inflammation of the heart.
“It appears that the virus lights a fire and the body’s own systems explode destroying the body,” says Rolfe. “This is known as a ‘Cytokine Storm.’”
There have been reports of COVID-19 patients experiencing ‘silent hypoxia’ dubbed ‘happy hypoxics’ – where an individual is coherent and able to function despite having critically impaired lung function.
“The happy hypoxics are the people who, because they are otherwise healthy, can tolerate lower oxygen levels,” says Rolfe. Eventually, however, the body’s tissues can’t get enough oxygen and lactic acid starts to build causing the patient to become short of breath.
“There is also some evidence that the virus interferes with oxygen binding to hemoglobin, which makes tissue hypoxia occur sooner and shortness of breath occur quicker,” he says. “The correlate to this would be high altitude induced hypoxia.”