Summary of demographic features, CK levels and comorbidities stratified by anti-cN-1A antibody status
| Anti-cN-1A positive | Anti-cN-1A negative | OR (95% CI) | p Value | |
|---|---|---|---|---|
| Gender (n=311) | ||||
| Female (%) | 42/102 (41.2) | 84/209 (40.2) | Referent | – |
| Male (%) | 60/102 (58.8) | 125/209 (59.8) | 0.96 (0.59 to 1.55) | 0.868 |
| Ethnicity (n=307) | ||||
| White (%) | 97/101 (96.0) | 199/206 (96.6) | Referent | – |
| Black (%) | 2/101 (2.0) | 4/206 (1.9) | 1.03 (0.19 to 5.70) | 0.977 |
| Asian (%) | 2/101 (2.0) | 3/206 (1.5) | 1.37 (0.23 to 8.32) | 0.734 |
| Other features | ||||
| Mean age in years at disease onset (SD) (n=301) | 61.6 (9.7) | 59.8 (9.5) | 1.02 (0.99 to 1.05) | 0.130 |
| Mean age in years at diagnosis (SD) (n=305) | 67.2 (9.3) | 65.3 (9.5) | 1.02 (1.00 to 1.05) | 0.089 |
| Disease duration in years at antibody testing (n=301) | Median 8.3 (IQR 5.0–12.0) Mean 9.0 (SD 5.5) | Median 7.6 (IQR 4.9–11.2) Mean 8.6 (SD 5.2) | 1.01 (0.97 to 1.06) | 0.604 |
| Highest CK level recorded (n=223) | Median 629.0 (IQR 392–850) Mean 774.8 (SD 563.4) | Median 600.0 (IQR 400–1012) Mean 1097.2 (SD 2583.4) | 1.00 (1.00 to 1.00) | 0.318 |
| Current or previous smoker (%) (n=189) | 21/52 (40.4) | 55/137 (40.2) | 1.01 (0.53 to 1.94) | 0.976 |
| Comorbidities | ||||
| Autoimmune disease (including Sjögren's syndrome) (%) (n=244) | 38/85 (44.7) | 54/159 (34.0) | 1.57 (0.92 to 2.70) | 0.100 |
| Of which, Sjögren's syndrome (%) (n=81) | 6/33 (18.2) | 8/48 (16.7) | 1.11 (0.35 to 3.57) | 0.859 |
| Malignancy (%) (n=275) | 12/85 (14.1) | 33/190 (17.4) | 0.78 (0.38 to 1.60) | 0.501 |
| Cardiovascular disease (%) (n=284) | 31/91 (34.1) | 64/193 (33.2) | 1.04 (0.62 to 1.76) | 0.880 |
| Hypertension (%) (n=181) | 29/60 (48.3) | 54/121 (44.6) | 1.16 (0.62 to 2.16) | 0.638 |
‘Disease duration in years at antibody testing’ refers to the time period between disease onset and the date of anti-cN-1A antibody testing. n represents data available for analysis per variable (of a total of 311). p Value is derived from logistic regression.
Anti-cN-1A, anticytosolic 5′-nucleotidase 1A; CK, creatine kinase.