Background
Methods
Study cohort
Clinical data
Biochemical parameters, auto-antibodies and HLA typing
Definition of disease conversion
Definition of disease remission
Statistical methods
Results
Characteristics of the Norwegian MCTD cohort
Demographics | Longitudinally observed patients (N = 118) | Lost to follow up (N = 13) | Deceased before re-examination (N = 16) |
---|---|---|---|
Age at T1, years, mean (SD) | 44 (14) | 48 (16) | 61 (13)a
|
Disease duration at T1 years, mean (SD) | 10 (8) | 11 (9) | 11 (7) |
Male gender, N (%) | 28 (24) | 1 (8) | 4 (25) |
Anti-RNP, U/mL, median (IQR) | 92 (19–240) | 91 (33–235) | 90 (4–196) |
Puffy handsb, N (%) | 108 (92) | 12 (92) | 14 (88) |
Arthritisb, N (%) | 92 (78) | 12 (92) | 12(75) |
Myositisb, N (%) | 36 (30) | 3 (23) | 6 (38) |
Pericarditisb, N (%) | 11 (9) | 2 (15) | 6 (38)c
|
Sclerodactyly, N (%) | 33 (28) | 6 (46) | 5 (31) |
Plevritisb, N (%) | 14 (12) | 3 (23) | 4 (25) |
Percentage DLCO pred, mean (SD) | 75 (19) | 75 (14) | 66 (16) |
Percentage FVC pred, mean (SD) | 93 (18) | 88 (19) | 88 (24) |
Interstitial lung disease, N (%) | 39 (34) | 4 (50) | 9 (69)d
|
The prevalence and prediction of phenotype stability
Demographics | Stable MCTD phenotype N = 104 | Diagnostic converters N = 14 |
---|---|---|
Age, years, mean (SD) | 43 (14) | 45 (13) |
Disease duration years, mean (SD) | 10 (9) | 9 (7) |
Male gender, N (%) | 27 (26) | 1 (7) |
Alarcon-Segovia’s criteria | 95 (91) | 13 (93) |
Kasukawa’s criteria | 89 (86) | 12 (86) |
Sharp’s criteria | 101 (97) | 13 (93) |
Interstitial lung disease, N (%) | 36 (36) | 3 (21) |
Cumulative frequency of clinical features | ||
Puffy hands, N (%) | 98 (94) | 10 (71)a
|
Arthritis, N (%) | 79 (76) | 13 (93) |
Myositis, N (%) | 34 (33) | 2 (14) |
Raynaud’s phenomenon, N (%) | 103 (99) | 14 (100) |
Sclerodactily, N (%) | 30 (29) | 3 (21) |
Leukocytopenia, N (%) | 30 (29) | 7 (50) |
Thrombocytopenia, N (%) | 17 (16) | 0 |
Facial erythema, N (%) | 44 (42) | 6 (43) |
Pericarditis, N (%) | 10 (10) | 1 (7) |
Pleuritis, N (%) | 13 (13) | 1 (7) |
Pulmonary function tests | ||
Percentage DLCO pred, mean (SD) | 74 (17) | 80 (14) |
Percentage FVC pred, mean (SD) | 92 (18) | 99 (14) |
Genetics and anti-RNP antibodies at T1 | ||
Anti-RNP, U/mL, median (IQR) | 27 (5–66) | 104 (25–240) |
HLA DRB1*04:01, N (%) | 49 (50) | 4 (31) |
The prevalence and prediction of remission
Clinical features present at T1 | Model 1: remissiona at T2 (N = 48) | Model 2: extended remissiona (N = 31) | Model 3: durable remissiona (N = 13) | ||||||
---|---|---|---|---|---|---|---|---|---|
OR | 95% CI |
P value | OR | 95% CI |
P value | OR | 95% CI |
P value | |
Increased CKb
| - | - | - | 3.18 | 1.17–8.67 | .024* | - | - | - |
Facial erythemab
| - | - | - | - | - | - | 0.11 | 0.01–0.81 | .030* |
Digital ulcersb
| - | - | - | 0.25 | 0.08–0.77 | .015* | - | - | - |
Trombocytopheniab,
c
| 0.05 | 0.01–-0.44 | .006** | - | - | - | - | - | - |
FVC % pred (pr 10%) | 1.37 | 1.04–1.79 | .026* | 1.56 | 1.13–2.16 | .007** | 1.71 | 1.04–2.80 | .033* |
NSAID medication | - | - | - | - | - | - | 0.05 | 0.00–0.73 | .028* |
Negative anti-RNP | - | - | - | - | - | - | 15.0 | 1.97–113.59 | .009** |