Table 1

Incidence rates of death in study subjects

TotalEvent (%)Total person-yearsIncidence rate (/105 years)IRR (95% CI)HR (95% CI)aHR (95% CI)
Before PSM
Group
None ILD1640220 (13.41)73962975Ref.Ref.Ref.
ILD16448 (29.27)60779082.66 (1.95 to 3.63)2.69 (1.97 to 3.68)1.73 (1.19 to 2.52)*
1:1 PSM
Group
None ILD15521 (13.55)7202918Ref.Ref.Ref.
ILD15543 (27.74)57874342.55 (1.51 to 4.29)4.38 (2.03 to 9.43)4.38 (2.03 to 9.43)†
  • *Adjusted for sex, age, level of urbanisation, low income, comorbidities (hypertension, hyperlipidaemia, myocardial infarction, congestive heart failure, peripheral vascular disease, cerebrovascular disease, peptic ulcer disease, mild liver disease, diabetes mellitus, diabetes with end-organ damage, hemiplegia, moderate to severe renal disease, tumour, metastatic solid tumour), use of medications (nonsteroidal anti-inflammatory drug, corticosteroid, methotrexate, sulfasalazine, leflunomide, hydroxychloroquine, tumour necrosis factor inhibitor, rituximab, cyclophosphamide and other immunosuppressant including ciclosporin, azathioprine, mycophenolate mofetil/mycophenolic acid) at baseline and time-averaged dose of medications during the follow-up periods.

  • †Conditional Cox regression analysis without adjusting variables which were not included in PSM.

  • aHR, adjusted HR; ILD, interstitial lung disease; IRR, incidence rate ratio; PSM, propensity score matching.