A team of researchers recently evaluated a new biomarker in interstitial lung disease to see whether or not it could predict disease severity and ultimately mortality.
Surfactant protein D or SP-D is a biomarker for many presentations of interstitial lung disease (ILD). Some of these forms are associated with myositis. This study in particular investigated patients whose lung disease was specifically related to polymyositis/dermatomyositis (PM/DM).
They wanted to understand whether or not this biomarker could help to predict morality for this patient cohort in particular.
This study included a total of 281 patients who were all diagnosed with an ILD associated with PM/DM. The study took place at multiple trial centers. It examined the levels of SP-D at baseline.
At the time that the patients were diagnosed, the following were noted-
- Demographic characteristics
- Clinical characteristics
- Existence of autoantibodies to MDA5
- Existence of autoantibodies to aminoacyl tRNA synthetase
Follow-up data were also collected.
A total of 78 ILD patients passed away during the observation period. The vast majority of these individuals died due to ILD.
For those who passed, the SP-D levels were much lower than those who survived. That said, the levels were still in the range of normal for these individuals.
All of the patients who had a SP-D level of 127.6 ng/mL or higher survived.
The researchers also found that the levels behaved differently for patients with different forms of antibodies. The presence of either the anti-MDA5 or the anti-ARS antibodies changed the SP-D levels for patients. Therefore, the evaluation of these levels as a predictor for disease severity should be investigated thoroughly.
You can read more about this study here.