JOURNAL ARTICLE

Ankylosing Spondylitis versus Nonradiographic Axial Spondyloarthritis: Comparison of Tumor Necrosis Factor Inhibitor Effectiveness and Effect of HLA-B27 Status. An Observational Cohort Study from the Nationwide DANBIO Registry

Bente Glintborg, Inge J Sørensen, Mikkel Østergaard, Lene Dreyer, Abdiweli A Mohamoud, Niels S Krogh, Oliver Hendricks, Lis S Andersen, Johnny L Raun, Marcin R Kowalski, Laura Danielsen, Randi Pelck, Henrik Nordin, Jens K Pedersen, Dorte G A Kraus, Susan R Christensen, Inger M J Hansen, Jakob Esbesen, Annette Schlemmer, Anne G Loft, Nabil Al Chaer, Lone Salomonsen, Merete L Hetland
Journal of Rheumatology 2017, 44 (1): 59-69
27909080

OBJECTIVE: To compare baseline disease activity and treatment effectiveness in biologic-naive patients with nonradiographic axial spondyloarthritis (nr-axSpA) and ankylosing spondylitis (AS) who initiate tumor necrosis factor inhibitor (TNFi) treatment and to study the role of potential confounders (e.g., HLA-B27 status).

METHODS: Observational cohort study based on prospectively registered data in the nationwide DANBIO registry. We used Kaplan-Meier plots, Cox, and logistic regression analyses to study the effect of diagnosis (nr-axSpA vs AS) and potential confounders (sex/age/start yr/HLA-B27/disease duration/TNFi-type/smoking/baseline disease activity) on TNFi adherence and response [e.g., Bath Ankylosing Spondylitis Activity Index (BASDAI) 50%/20 mm].

RESULTS: The study included 1250 TNFi-naive patients with axSpA (29% nr-axSpA, 50% AS, 21% lacked radiographs of sacroiliac joints). Patients with nr-axSpA were more frequently women (50%/27%) and HLA-B27-negative (85/338 = 25%), compared to AS (81/476 = 17%; p < 0.01). At TNFi start patients with nr-axSpA had higher visual analog scale scores [median (quartiles)] for pain: 72 mm (55-84)/65 mm (48-77); global: 76 mm (62-88)/68 mm (50-80); fatigue: 74 mm (55-85)/67 mm (50-80); and BASDAI: 64 (54-77)/59 (46-71); all p < 0.01. However, patients with nr-axSpA had lower C-reactive protein: 7 mg/l (3-17)/11 mg/l (5-22); and BAS Metrology Index: 20 (10-40)/40 (20-50); all p < 0.01. Median (95% CI) treatment adherence was poorer in nr-axSpA than in AS: 1.59 years (1.15-2.02) versus 3.67 years (2.86-4.49), p < 0.0001; but only in univariate and not confounder-adjusted analyses (p > 0.05). Response rates were similar in AS and nr-axSpA (p > 0.05). HLA-B27 negativity was associated with poorer treatment adherence [HLA-B27 negative/positive, nr-axSpA: HR 1.74 (1.29-2.36), AS: HR 2.04 (1.53-2.71), both p < 0.0001]; and lower response rates (nr-axSpA: 18/61 = 30% vs 93/168 = 55%; AS: 17/59 = 29% vs 157/291 = 54%, both p < 0.05).

CONCLUSION: In this nationwide cohort, patients with nr-axSpA had higher subjective disease activity at start of first TNFi treatment, but similar outcomes to patients with AS after confounder adjustment. HLA-B27 positivity was associated with better outcomes irrespective of axSpA subdiagnosis.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
27909080
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"