Kaplan Meier survival curves for RA patients showing the relationship between baseline serum levels of metalloproteinase (MMP)-8 and mortality due to respiratory disease or pneumonia alone. (A) Respiratory disease. (B) Pneumonia alone. For these analyses, the levels of MMP-8 were divided into those below (<) or equal to and above (≥) the median (20.07 ng/ml).
Mattey et al. Arthritis Research & Therapy 2012 14:R204 doi:10.1186/ar4042