Anti-TNF therapy for inflammatory bowel disease appears to double the relative risk of developing central demyelinating disease, though the absolute risk remains small, according to a preliminary report published online Oct. 5 in JAMA Internal Medicine.
Previous case reports have suggested a possible association between anti-TNF agents taken for IBD and later development of demyelinating diseases, but a definitive link has been difficult to establish because of the rarity of these disorders and the suspicion that there already may be an underlying association between IBD and demyelinating disease.
Dr. Nynne Nyboe Andersen
So researchers examined the issue by analyzing data from nationwide Danish health registries for IBD patients and medication exposure. They identified 4,504 patients treated during a 14-year period who had IBD and took anti-TNF agents, and 16,429 IBD patients matched for sex, age, and IBD duration who did not take the medications, according to Dr. Nynne Nyboe Andersen, of the department of epidemiology research, Statens Serum Institut, Copenhagen, and her associates.
Eleven patients in the exposed group had central demyelinating events: multiple sclerosis (2 patients), optic neuritis (5 patients), or other central demyelinating disease (4 patients). For exposed patients, there were 7.5 events per 10,000 person-years.
In comparison, 17 patients in the unexposed group had central demyelinating events: multiple sclerosis (5 patients), optic neuritis (6 patients), transverse myelitis (1 patient), or other central demyelinating disease (5 patients). In this group there were 3.3 events per 10,000 person-years.
The hazard ratio for developing central demyelinating disease after exposure to anti-TNF agents was 2.19, the investigators wrote (JAMA Intern Med. 2015 Oct 5, doi:10.1001/jamainternmed.2015.5396.).
These preliminary findings represent the first report of this association and must be confirmed in future studies, according to the researchers.
“If true, the observed association could either be attributed to the unmasking of a latent demyelinating disease or to the emergence of a de novo demyelinating disease,” Dr. Nyboe Andersen and her associates wrote in the research letter.
The study was supported by the Lundbeck Foundation, Women in Science, the Beckett Foundation, the Danish Colitis Crohn Association, and the Danish Council for Independent Research. Dr. Nyboe Andersen reported receiving travel and speaking fees from MSD and speaking fees from Ferring, and one of her associates reported receiving travel and speaking fees from AbbVie.