According to a story from Pulmonary Advisor, the rare condition pulmonary arterial hypertension (PAH) is mostly known for the impacts that it can have on the lungs and on the overall function of the respiratory system. With that being said, many patients with the condition experience other symptoms that are not directly linked to the lungs. In recent years, a mounting body of evidence suggests that these external symptoms are driven by the same mechanisms that cause the condition to appear.
About Pulmonary Arterial Hypertension (PAH)
Pulmonary arterial hypertension is a condition in which the blood pressure in the arteries of the lungs is abnormally high. The cause of pulmonary arterial hypertension is often unknown in many cases. However, there are a variety of potential causes, such as certain heritable genetic mutations, exposure to certain toxins, and drug use (ex. methamphetamine). It can also appear as a symptom or complication in a number of other diseases, such as heart disease, connective tissue disease, and infection with HIV. The arteries in the lungs are often inflamed. Symptoms of this condition include rapid heartbeat, poor exercise tolerance, shortness of breath, fainting, leg swelling, fatigue, and chest pain. Treatment may include a number of medications and surgical operations, including lung transplant. A transplant can cure the condition, but it can cause many complications. Survival rate is often only about two or three years without treatment, but the latest drugs can prolong life by several years or more. Click here to learn more about pulmonary arterial hypertension.
Research suggests that this condition does not just impact the lungs directly and is in fact a multi-system disease. Common comorbidities of the illness include renal insufficiency, dysfunction of the thyroid, depression, and diabetes. However, this is just the tip of the iceberg. Many of these problems suggest a broader manifestation of dysfunction that impacts the vascular circulatory system.
A reduction in cerebral bloodflow has been documentary in pulmonary arterial hypertension. Other clues include reduced dilation of the branchial artery and elevated rates of chronic kidney disease. It is unclear if kidney disease precipitates the condition or vice-versa. Hyperthyroidism appears to contribute to pulmonary arterial hypertension in some patients, with symptoms resolving once the dysfunction is managed successfully; other patients experience hypothyroidism instead.
There is also evidence of muscle protein degradation and weakened overall muscle strength, as well as changes to mitochondrial function. This could explain symptoms like fatigue and poor exercise tolerance, which were previously attributed to the effects that condition can have on the heart.
While the future implications for disease research remain unclear, there is no doubt that appropriate treatment of pulmonary arterial hypertension requires screening for extrapulmonary comorbidities.