Does effect of smoking on the serum levels of 25-hydroxyvitamin D depend on the assay employed?
These two studies indicate that the ECLIA (Roche) overestimates serum 25(OH)D levels in smokers by unknown mechanisms. If confirmed, this might have clinical consequences, and the issue needs further exploration.
The TNFalpha gene does not seem to be associated with severity as assessed by erosive outcome at 5 years in patients with IP.