Pulmonary Arterial Hypertension and Nonspecific Interstitial Pneumonia

Pulmonary arterial hypertension (PAH) commonly occurs in chronic interstitial lung disease and idiopathic pulmonary fibrosis, conditions in which nonspecific interstitial pneumonia (NSIP) is also often found. For those suffering disorders of the lung, it is important to understand more about PAH and NSIP, including current means of diagnosis, as well as management and treatment options.

What is Pulmonary Arterial Hypertension?

PAH refers to high blood pressure in the lungs. It is a condition that worsens over time and can be potentially fatal, since increased pressure in the lung arteries can strain the heart and cause heart failure. Symptoms can include shortness of breath, increased pressure in the chest, as well as dizziness, fatigue, inability to exercise, and low blood pressure.

Currently, the condition is diagnosed using echocardiographic assessment and right heart catheterization. These tests measure lung and heart function, and the amount of oxygen in the blood.

PAH is one of five types of pulmonary hypertension. The disease can be associated with other conditions, including lung disease, heart disease, infections such as HIV, illegal drug use, or autoimmune diseases such as scleroderma or lupus. Genetics, in part, can determine whether someone develops PAH. Although PAH incidence increases with age, people of any age may develop PAH.

Although PAH currently has no cure, several medications are used to control symptoms. Vasodilators, for example, are used to control and improve symptoms, but they do not halt the progression of the disease.

What is NSIP?

NSIP is a fairly uncommon disease that affects the tiny air sacs, called alveoli, found within the lungs. The walls of the alveoli become swollen, as does the thin covering that protects the lungs, called the pleura. Two forms of NSIP exist, known as cellular and fibrotic. In the fibrotic form, there is additional scarring and the prognosis is poorer.

Symptoms of  NSIP include a dry cough, shortness of breath, difficultly in breathing, fatigue, and fingertip enlargement, known as “clubbing.”

Treatments for NSIP include the corticosteroid prednisone, which can have a number of side effects. Other immune-suppressing medications may also be used. Medication treatment is often more aggressive for the fibrotic type, to prevent scarring.

As noted by researchers in the case study “Pulmonary hypertension in chronic interstitial lung diseases,” published in European Respiratory Review, the frequency of occurrence and clinical features of pulmonary hypertension in patients with idiopathic NSIP are not fully understood due to a lack of reliable data. But it is believed that PH is most often diagnosed in interstitial lung diseases (ILDs) that involve connective tissue diseases, whose underlying trigger is often nonspecific interstitial pneumonia (NSIP). When connective tissue disease is not present in a patient with ILD-associated PH, researchers have noted that mean pulmonary artery pressures (mPAP) are usually not considered to be severe. Exceptions exist, however, as highlighted in this case study.

While it can be difficult to identify NSIP as a basis for severe pulmonary hypertension, due to the fact that the signs of the disease are more subtle than those in idiopathic pulmonary arterial hypertension, the condition can lead to serious pulmonary vascular remodeling. It requires an accurate diagnosis as early as possible.

Although current treatments for PAH and NSIP focus on symptom management, new studies of antioxidant inflammation modulators could provide hope of future disease-modifying therapies. In general, more research is needed to understand not only how PAH and NSIP might be managed, but also into ways of reducing their severity and, possibly, preventing them in the first place.

Note: Pulmonary Hypertension News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.