Measuring how your IPF (Idiopathic Pulmonary Fibrosis) is doing is a very important part of regular visits with your pulmonologist. Tests that have been shown to have value include pulmonary function tests (breathing tests), six minute walk tests, your oxygen saturation at rest and with exercise, and how you perceive your symptoms (what activities cause you to be short of breath). Regular chest Xrays are not very good at detecting subtle changes and frequent CT scans are expensive and impractical.
Based on a collection of information gathered from the above tests, your lung doctor is able to determine whether you are staying stable or getting worse (or occasionally getting better).
The following are important markers of worsening pulmonary fibrosis
- Forced Vital Capacity (FVC): 5% decline is mildly worrisome, 10% decline is very worrisome
- Diffusion Capacity (DCO): 5% decline is mildly worrisome, 10% decline is very worrisome
- Six minute walk distance: distance less than 250 meters (820 ft.), or decline in walk distance of greater than 50 meters (164 ft.)
- Low oxygen saturation at rest or with exercise
- Progressive scarring or fibrosis on your chest imaging
- Increased fatigue and decreased ability to complete your usual activities
What is the best course of action if you are getting worse despite taking one of the two approved medications for IPF?
Patients that are interested in being treated for Idiopathic Pulmonary Fibrosis are treated with either OFEV or Esbriet. If there is evidence of gradual worsening despite taking one of the approved medications then it is reasonable to switch to the other agent. At present, we have not had success in getting insurance to pay for both agents at the same time as there is no data available supporting such a strategy.
Patients who experience a more rapid decline over days to a few weeks are in a particularly high risk and we label this decline as an acute/subacute exacerbation of IPF. A rapid evaluation is undertaken to identify if there are other causes such as pneumonia, heart failure or blood clots in the lungs. Although data supporting a particular management strategy are lacking, most doctors treat with a short course of steroids and antibiotics.
Patients who experience either gradual or more rapid decline are at increased risk of progressing and dying from their lung disease. Lung transplant evaluation is often appropriate in this group. For patients that are not actively listed for lung transplantation, participation in a clinical research study is an important option.