Short breath, frequent coughing while walking could signal pulmonary fibrosis

The number of patients with pulmonary fibrosis -- a condition in which the lungs gradually harden -- has been rising significantly in Korea in recent years, in line with the aging population and requiring greater medical attention.

Idiopathic pulmonary fibrosis, in which no specific cause is identified, accounts for 20–30 percent of all cases. More than 200 other types of pulmonary fibrosis have also been identified. According to the Korea Disease Control and Prevention Agency’s Statistical Yearbook on Rare Disease Patients, the number of idiopathic pulmonary fibrosis cases totaled 3,737 in 2020 and rose to 4,450 in 2021 -- an increase of about 20 percent in just one year.

Pulmonary fibrosis is a rare disease with a poorer prognosis than many cancers, as it is difficult to detect early and challenging to treat.

“Pulmonary fibrosis is a rare disease that is difficult to diagnose and treat. Some studies show poor outcomes, with survival rates below 50 percent at five years after diagnosis, leading doctors to consider it a disease worse than cancer,” said Professor Cho Jun-yeon of the Department of Respiratory Medicine at Chungbuk National University Hospital, speaking on the hospital’s YouTube channel.

When should pulmonary fibrosis be suspected?

“The most characteristic symptom of pulmonary fibrosis is shortness of breath, especially when climbing hills or walking quickly. In advanced cases, even minimal movement can cause breathlessness. This symptom usually develops gradually over months or years, though it can sometimes worsen rapidly. Patients often cough frequently, but usually without phlegm,” Professor Cho explained.

“Some patients may produce clear, mucus-like phlegm. Fatigue is also common. If you experience shortness of breath while walking and frequent coughing, consult a nearby hospital. If necessary, visit a university hospital for a consultation with a respiratory medicine specialist,” Cho advised.

Most patients are over 65 years old, and the majority are male. Pulmonary fibrosis is also strongly associated with smoking.

What happens to the lungs in pulmonary fibrosis?

“Our body is composed of many cells that require oxygen to function. When we breathe, oxygen enters the lungs through bronchi and then passes into the blood via the alveoli (air sacs). For alveoli and blood vessels to function properly, they need a supportive structure called the interstitium,” Professor Cho explained, noting that pulmonary fibrosis occurs when this interstitium gradually thickens.

As the disease progresses, the lungs stiffen and the alveoli lose function. While idiopathic pulmonary fibrosis develops without a known cause, the condition can also occur alongside autoimmune diseases such as rheumatoid arthritis. Regardless of cause, thickening of the interstitium impairs oxygen transfer, leading to the hallmark symptom of shortness of breath.

How is pulmonary fibrosis diagnosed?

When pulmonary fibrosis is suspected, physicians first assess risk factors such as occupation, hobbies, medications, and pet ownership to determine potential exposure to harmful environments.

“We assess disease severity through pulmonary function tests and the 6-minute walk test. Sometimes, a cardiac ultrasound is needed. A chest CT scan is absolutely essential and plays the most critical role in diagnosis. CT images of patients with advanced pulmonary fibrosis show a honeycomb pattern,” Cho said.

“If honeycomb shadows are clearly present, pulmonary fibrosis can be diagnosed without a biopsy. If CT results are insufficient, lung tissue analysis is required. To obtain lung tissue, either bronchoscopy or surgery can be performed. Because large samples are needed, surgical biopsy is more accurate than bronchoscopy. Today, thoracoscopic surgery is primarily used, reducing the risks of general anesthesia.”

Hardened lungs cannot be reversed, making early diagnosis vital

Once the lungs stiffen due to pulmonary fibrosis, they cannot be restored, even with treatment, making early detection critical.

“Pulmonary fibrosis is primarily treated with medication. Currently, two oral drugs are used: pirfenidone (brand name Pirespa) and nintedanib (Ofev). These drugs work by suppressing fibroblast activity, which causes the lungs to stiffen,” Professor Cho noted. “However, even these drugs cannot return the lungs to their original state once hardened.”

Still, drug therapy can slow progression and reduce the risk of acute deterioration.

“Studies have shown that medication improves survival compared to no treatment,” Cho said. “As with all drugs, side effects exist, including nausea, vomiting, indigestion, diarrhea, appetite loss, and skin rashes. Because of these, some patients discontinue therapy.”

Fortunately, many promising new drug trials are underway.

“As the disease advances, patients may require home oxygen therapy. For those who are younger and otherwise healthy at the end stage, lung transplantation can be considered,” Professor Cho said. “In addition, multiple clinical trials for new therapies are ongoing, offering hope for better outcomes in the future.”