Background
Methods
Patients
Physical examination and questionnaires
Radiography
Laboratory tests
Statistics
Results
Patients
Total group | Men (n = 89) | Women (n = 77) | p value | |
---|---|---|---|---|
Demographic variables | ||||
Age, years | 50 (13) | 49 (12) | 51 (13) | 0.45 |
Current smokers | 17 (10) | 8 (9) | 9 (12) | 0.75 |
Ever-smokers | 72 (43) | 41 (46) | 31 (40) | 0.55 |
BMI category: normal/overweight/obese | 85 (51)/ | 41 (46)/ | 44 (57)/ | 0.36 |
56 (34)/ | 33 (37)/ | 23 (30)/ | ||
25 (15) | 15 (17) | 10 (13) | ||
Blue-collar workera | 40 (33) | 21 (33) | 19 (33) | 1.00 |
Time between x-rays, months | 66 (3) | 65 (3) | 67 (1) | 0.003 |
Disease-related variables | ||||
Duration of symptoms, years | 24 (13) | 23 (13) | 24 (13) | 0.58 |
History of anterior uveitis | 85 (51) | 50 (56) | 35 (46) | 0.22 |
History of peripheral arthritis | 95 (57) | 47 (53) | 48 (62) | 0.28 |
History of coxitis | 13 (8) | 7 (8) | 6 (8) | 1.00 |
BASMI, score | 3.0 (1.5) | 3.2 (1.8) | 2.9 (1.2) | 0.61 |
BASFI, score | 2.5 (2.0) | 2.3 (1.9) | 2.7 (2.1) | 0.25 |
BASDAI, score | 3.4 (2.1) | 3.1 (2.1) | 3.7 (2.0) | 0.056 |
ASDAS_CRP, score | 2.1 (0.9) | 2.1 (0.9) | 2.1 (0.8) | 0.53 |
CRP, mg/L | 5.4 (8.5) | 6.5 (10.5) | 4.2 (5.1) | 0.26 |
Time-averaged CRP during follow up, mg/L | 5.8 (5.9) | 6.5 (6.4) | 4.9 (5.0) | 0.043 |
ESR, mm/h | 14.2 (11.2) | 12.7 (11.5) | 15.9 (10.6) | 0.003 |
Time-averaged ESR during follow-up, mm/h | 12.2 (8.4) | 10.9 (7.8) | 13.8 (8.9) | 0.009 |
HLA-B27 positive | 143 (86) | 82 (92) | 61 (79) | 0.030 |
Aortic insufficiencyb | 25 (16) | 13 (16) | 12 (17) | 0.98 |
mSASSS, score | 13.9 (18.6) | 20.3 (21.9) | 6.4 (9.6) | < 0.001 |
Presence of syndesmophyte | 76 (46) | 51 (57) | 25 (33) | 0.002 |
Medications | ||||
Patients on NSAIDs baseline | 129 (78) | 66 (74) | 63 (82) | 0.32 |
NSAID index during follow up, 0–100 | 34 (38) | 39 (39) | 29 (33) | 0.31 |
Patients on TNFi at baseline | 33 (20) | 22 (25) | 11 (14) | 0.14 |
Patients exposed to TNFi during follow up | 49 (30) | 30 (34) | 19 (25) | 0.27 |
Patients on bisphosphonate at baseline | 7 (4) | 1 (1) | 6 (8) | 0.050 |
Patients exposed to bisphosphonate during follow-up | 30 (18) | 11 (12) | 19 (25) | 0.064 |
Spinal radiographic progression
Predictors of progression defined as increase of ≥ 2 mSASSS units or new syndesmophyte development over 5 years in univariate analyses (Tables 2 and 3)
Total group, n = 166 | Men, n = 89 | Women, n = 77 | |||||||
---|---|---|---|---|---|---|---|---|---|
OR | 95% CI | p value | OR | 95% CI | p value | OR | 95% CI | p value | |
Demographic variables | |||||||||
Male sex | 2.32 | 1.14 to 4.72 |
0.020
| NA | NA | ||||
Age, years | 1.03 | 1.01 to 1.06 |
0.021
| 1.03 | 1.00 to 1.07 | 0.078 | 1.05 | 1.00 to 1.10 | 0.075 |
BMI: overweight (reference, normal) | 2.40 | 1.09 to 5.26 |
0.029
| 2.62 | 0.95 to 7.21 | 0.062 | 1.76 | 0.47 to 6.54 | 0.40 |
obese (reference, normal) | 5.06 | 1.93 to 13.24 |
0.001
| 5.33 | 1.50 to 19.0 |
0.010
| 4.22 | 0.91 to 19.51 | 0.065 |
Ever-smoker | 1.74 | 0.88 to 3.44 | 0.11 | 3.53 | 1.42 to 8.77 |
0.007
| 0.47 | 0.14 to 1.65 | 0.24 |
Current smoker | 1.44 | 0.50 to 4.14 | 0.50 | 3.33 | 0.74 to 15.00 |
0.12
| 0.48 | 0.06 to 4.18 | 0.51 |
Blue-collar worka | 1.31 | 0.55 to 3.12 | 0.55 | 1.00 | 0.31 to 3.19 | 1.00 | 1.91 | 0.50 to 7.29 | 0.35 |
Time between x-rays, months | 0.92 | 0.81 to 1.05 | 0.21 | 0.96 | 0.83 to 1.11 | 0.57 | 1.15 | 0.66 to 2.00 | 0.63 |
Disease-related variables | |||||||||
Duration of symptoms, years | 1.02 | 0.99 to 1.04 | 0.24 | 1.01 | 0.98 to 1.05 | 0.57 | 1.03 | 0.99 to 1.08 | 0.17 |
HLA-B27 positive | 1.50 | 0.52 to 4.30 | 0.45 | 1.44 | 0.26 to 7.90 | 0.67 | 1.06 | 0.26 to 4.33 | 0.93 |
History of coxitis | 0.74 | 0.20 to 2.83 | 0.66 | 0.27 | 0.03 to 2.39 | 0.24 | 2.23 | 0.37 to 13.51 | 0.38 |
History of uveitis | 2.33 | 1.16 to 4.71 |
0.018
| 2.28 | 0.92 to 5.66 | 0.076 | 2.08 | 0.66 to 6.56 | 0.21 |
BASMI, score | 1.65 | 1.29 to 2.10 |
< 0.001
| 1.43 | 1.10 to 1.86 |
0.008
| 2.58 | 1.42 to 4.69 |
0.002
|
Lateral spinal flexion, cm | 0.89 | 0.84 to 0.96 |
0.001
| 0.91 | 0.84 to 0.98 |
0.014
| 0.83 | 0.71 to 0.96 |
0.012
|
BASFI, score | 1.15 | 0.97 to 1.36 | 0.10 | 1.13 | 0.90 to 1.42 | 0.28 | 1.27 | 0.96 to 1.67 | 0.089 |
BASDAI, score | 0.98 | 0.83 to 1.15 | 0.80 | 0.93 | 0.76 to 1.15 | 0.52 | 1.17 | 0.87 to 1.56 | 0.30 |
ASDAS_CRP, score | 1.14 | 0.78 to 1.68 | 0.51 | 1.12 | 0.70 to 1.80 | 0.64 | 1.24 | 0.63 to 2.46 | 0.54 |
CRP, mg/L | 1.06 | 1.02 to 1.11 |
0.008
| 1.05 | 1.00 to 1.10 | 0.051 | 1.09 | 0.99 to 1.21 | 0.083 |
Time-averaged CRP, mg/L | 1.08 | 1.02 to 1.14 |
0.010
| 1.09 | 1.01 to 1.17 |
0.035
| 1.05 | 0.95 to 1.16 | 0.36 |
ESR, mm/h | 1.02 | 0.99 to 1.05 | 0.19 | 1.02 | 0.98 to 1.06 | 0.39 | 1.04 | 0.99 to 1.09 | 0.10 |
Time-averaged ESR, mm/h | 1.03 | 0.99 to 1.07 | 0.11 | 1.05 | 0.99 to 1.11 | 0.097 | 1.04 | 0.98 to 1.10 | 0.21 |
Syndesmophytes at baseline | 6.46 | 2.98 to 14.03 |
< 0.001
| 5.55 | 1.98 to 15.54 |
0.001
| 6.27 | 1.85 to 21.24 |
0.003
|
mSASSS baseline, units | 1.04 | 1.02 to 1.05 |
< 0.001
| 1.02 | 1.00 to 1.04 |
0.046
| 1.11 | 1.04 to 1.19 |
0.001
|
Aortic insufficiencyb | 1.20 | 0.48 to 3.03 | 0.70 | 1.20 | 0.35 to 4.06 | 0.77 | 1.28 | 0.30 to 5.46 | 0.74 |
Medication | |||||||||
NSAID index, 0–100 | 1.01 | 1.00 to 1.01 | 0.26 | 1.00 | 0.99 to 1.02 | 0.52 | 1.00 | 0.99 to 1.02 | 0.62 |
Exposure to TNFi | 1.17 | 0.56 to 2.43 | 0.67 | 0.84 | 0.33 to 2.12 | 0.71 | 1.71 | 0.50 to 5.85 | 0.39 |
Exposure to bisphosphonates | 2.29 | 1.01 to 5.21 |
0.047
| 1.57 | 0.44 to 5.63 | 0.49 | 5.30 | 1.59 to 17.69 |
0.007
|
Total group, n = 166 | Men, n = 89 | Women, n = 77 | |||||||
---|---|---|---|---|---|---|---|---|---|
OR | 95% CI | p value | OR | 95% CI | p value | OR | 95% CI | p value | |
Demographic variables | |||||||||
Male sex | 3.29 | 1.44 to 7.54 |
0.005
| NA | NA | ||||
Age, years | 1.05 | 1.02 to 1.09 |
0.003
| 1.06 | 1.02 to 1.10 |
0.007
| 1.06 | 0.99 to 1.13 | 0.082 |
BMI: overweight (reference, normal) | 2.46 | 1.04 to 5.85 |
0.042
| 3.16 | 1.08 to 9.22 |
0.036
| 0.95 | 0.16 to 5.63 | 0.96 |
obese (reference, normal) | 4.49 | 1.62 to 12.44 |
0.004
| 4.25 | 1.16 to 15.60 |
0.029
| 4.29 | 0.78 to 23.43 | 0.093 |
Ever-smoker | 1.22 | 0.58 to 2.56 | 0.60 | 1.73 | 0.70 to 4.31 | 0.24 | 0.38 | 0.07 to 1.99 | 0.25 |
Current smoker | 2.16 | 0.74 to 6.32 | 0.16 | 4.47 | 0.99 to 20.29 | 0.052 | 0.94 | 0.10 to 8.51 | 0.95 |
Blue-collar worka | 1.18 | 0.45 to 3.10 | 0.74 | 1.47 | 0.44 to 4.87 | 0.53 | 0.78 | 0.14 to 4.43 | 0.78 |
Time between x-rays | 0.82 | 0.71 to 0.94 |
0.004
| 0.88 | 0.75 to 1.02 | 0.083 | 0.75 | 0.36 to 1.56 | 0.44 |
Disease-related variables | |||||||||
Duration of symptoms, years | 1.02 | 0.99 to 1.05 | 0.13 | 1.02 | 0.99 to 1.06 | 0.26 | 1.04 | 0.98 to 1.09 | 0.18 |
HLA-B27 positive | 1.00 | 0.34 to 2.90 | 1.00 | 0.55 | 0.12 to 2.65 | 0.46 | 0.91 | 0.17 to 4.86 | 0.91 |
History of coxitis | 1.09 | 0.28 to 4.19 | 0.90 | 0.36 | 0.04 to 3.14 | 0.35 | 4.57 | 0.71 to 29.61 | 0.11 |
History of uveitis | 2.26 | 1.04 to 4.91 |
0.039
| 1.88 | 0.73 to 4.81 | 0.19 | 2.69 | 0.62 to 11.66 | 0.19 |
BASMI, score | 1.57 | 1.22 to 2.01 |
< 0.001
| 1.29 | 1.00 to 1.68 | 0.053 | 4.39 |
1.77 to 10.84
|
0.001
|
Lateral spinal flexion, cm | 0.89 | 0.83 to 0.96 |
0.002
| 0.92 | 0.85 to 1.00 |
0.036
| 0.71 | 0.55 to 0.91 |
0.006
|
BASFI, score | 1.14 | 0.95 to 1.36 | 0.16 | 1.11 | 0.88 to 1.40 | 0.40 | 1.35 | 0.97 to 1.87 | 0.072 |
BASDAI, score | 1.01 | 0.85 to 1.21 | 0.91 | 1.01 | 0.82 to 1.26 | 0.90 | 1.14 | 0.81 to 1.61 | 0.45 |
ASDAS_CRP | 1.23 | 0.81 to 1.86 | 0.34 | 1.19 | 0.73 to 1.95 | 0.48 | 1.44 | 0.63 to 3.32 | 0.39 |
CRP, mg/L | 1.02 | 0.99 to 1.06 | 0.24 | 1.02 | 0.98 to 1.06 | 0.46 | 1.01 | 0.89 to 1.15 | 0.86 |
Time-averaged CRP, mg/L | 1.06 | 1.00 to 1.12 | 0.060 | 1.05 | 0.98 to 1.13 | 0.15 | 1.03 | 0.91 to 1.16 | 0.65 |
ESR, mm/h | 0.99 | 0.95 to 1.02 | 0.43 | 1.00 | 0.96 to 1.04 | 0.83 | 0.99 | 0.92 to 1.06 | 0.69 |
Time-averaged ESR, mm/h | 0.99 | 0.94 to 1.03 | 0.60 | 1.00 | 0.94 to 1.06 | 0.94 | 1.00 | 0.93 to 1.09 | 0.93 |
Syndesmophytes at baseline | 5.98 | 2.52 to 14.17 |
< 0.001
| 5.01 | 1.68 to 14.92 |
0.004
| 5.16 | 1.17 to 22.74 |
0.030
|
Aortic insufficiencyb | 1.53 | 0.58 to 4.04 | 0.40 | 1.11 | 0.31 to 4.02 | 0.87 | 2.89 | 0.61 to 13.69 | 0.18 |
Medication | |||||||||
NSAID index, 0–100 | 1.01 | 1.00 to 1.02 | 0.11 | 1.01 | 1.00 to 1.02 | 0.11 | 1.00 | 0.97 to 1.02 | 0.72 |
Exposure to TNFi | 1.07 | 0.48 to 2.38 | 0.88 | 0.59 | 0.22 to 1.62 | 0.31 | 2.83 | 0.67 to 11.86 | 0.16 |
Exposure to bisphosphonates | 2.57 | 1.09 to 6.08 |
0.031
| 2.12 | 0.59 to 7.67 | 0.25 | 8.46 | 1.87 to 38.38 |
0.006
|
Predictors of progression defined as increase of ≥ 2 mSASSS units or new syndesmophyte development over 5 years in multivariate analyses (Figs. 3 and 4)
Effect of treatment with bisphosphonates in PS-adjusted analyses in the whole study population
Progression ≥ 2 mSASSS units | New syndesmophytes | |||
---|---|---|---|---|
OR (95% CI) | p value | OR (95% CI) | p value | |
Exposure to bisphosphonates | 2.47 (0.89 to 6.86) | 0.083 | 2.96 (1.02 to 8.62) |
0.046
|
Propensity score, 0–1 | 0.32 (0.03 to 3.65) | 0.36 | 0.41 (0.03 to 5.59) | 0.51 |
Exposure to TNFi | 0.91 (0.40 to 2.08) | 0.83 | 1.05 (0.43 to 2.52) | 0.92 |
Propensity score, 0–1 | 6.26 (0.78 to 49.89) | 0.084 | 1.18 (0.12 to 11.30) | 0.89 |
TNFi for ≥ 2 years | 0.86 (0.35 to 2.09) | 0.73 | 0.81 (0.30 to 2.21) | 0.68 |
Propensity score, 0–1 | 3.78 (0.41 to 34.593) | 0.24 | 0.69 (0.06 to 8.46) | 0.77 |
Effect of treatment with TNFi in PS-adjusted analyses in the whole study population
Univariate OR (95% CI) | p value | OR (95% CI) with PSa | p value | |
---|---|---|---|---|
Progression ≥ 2 mSASSS units | ||||
TNFi vs. no TNFi and no NSAID | 3.33 (0.46 to 24.05) | 0.23 | 3.06 (0.27 to 34.70) | 0.37 |
TNFi vs. no TNFi and low NSAID | 1.24 (0.46 to 3.38) | 0.67 | 1.16 (0.40 to 3.40) | 0.79 |
TNFi vs. no TNFi and high NSAID | 0.74 (0.17 to 3.31) | 0.70 | 0.48 (0.09 to 2.48) | 0.38 |
New syndesmophytes | ||||
TNFi vs. no TNFi and no NSAID | 1.25 (0.14 to 10.94) | 0.84 | 2.51 (0.17 to 38.18) | 0.51 |
TNFi vs. no TNFi and low NSAID | 1.26 (0.42 to 3.81) | 0.67 | 1.44 (0.44 to 4.70) | 0.55 |
TNFi vs. no TNFi and high NSAID | 1.04 (0.23 to 4.69) | 0.96 | 0.84 (0.17 to 4.21) | 0.83 |