Univariable logistic regression for connective tissue disease associated interstitial lung disease (CTD-ILD) diagnosis

Unadjusted OR95% CIp-valueAUC
Nailfold characteristics
 Density <6/mm7.472.73–20.43<0.001#0.72
 Giant ≥3 total6.772.43–18.81<0.001#0.70
 Avascular ≥2 total5.442.02–14.680.001#0.68
 Microhaemorrhages ≥1 total5.001.08–23.180.040#0.61
Baseline characteristics
 FVC % predicted1.010.99–1.040.2790.59
DLCO % predicted1.031.00–1.060.0320.64
Clinical CTD manifestations
 Any CTD manifestation42.1810.80–164.74<0.001#0.86
Serology and radiology
 ANA ≥1:3203.801.42–10.140.0080.64
 Positive ENA5.382.04–14.200.001#0.68
 Any myositis autoantibody+0.330.10–1.050.0610.60
 Radiological NSIP, OP or NSIP/OP7.482.33–23.930.001#0.71

Odds ratios (OR) are shown for the bivariate relationship of each variable with CTD-ILD diagnosis. FVC %: percentage predicted forced vital capacity; DLCO %: percentage predicted diffusing capacity for carbon monoxide; ANA: antinuclear antibodies; ENA: extractable nuclear antibodies; NSIP: nonspecific interstitial pneumonia pattern on radiology; OP: organising pneumonia pattern on radiology; #: remains significant adjusted for age, sex, smoking, FVC%, treatment and pulmonary hypertension; : including any of inflammatory arthritis, Raynaud's phenomenon, digital oedema, palmar telangiectasia, digital tip ulceration, mechanic's hands, Gottron's papules/sign, sclerodactyly; +: patients with positive myositis autoantibody and no clinical features of myositis classified as IPAF (non-CTD-ILD).