Table 2

Associations between emphysema on CT, per cent emphysema, and mortality due to lung disease in the Multi-Ethnic Study of Atherosclerosis, 2000–2013

Underlying cause of deathEmphysema on CT (dichotomous)Per cent emphysema (continuous)
Absent (N=6233)Present (N=538)p ValueAll (N=6784)p Value
Respiratory diseases
 Person-years71 845607877 750
 Mortality rate per 10 000 person-years7.929.69.9
 HRcrude (95% CI)1.00 (referent)3.67 (2.16–6.25)<0.0011.48 (1.35–1.63)<0.001
 HRadjusted (95% CI)1.00 (referent)2.94 (1.68–5.15)<0.0011.51 (1.35–1.69)<0.001
 Person-years71 845607877 750
 Mortality rate per 10 000 person-years2.828.05.0
 HRcrude (95% CI)1.00 (referent)10.11 (5.25–19.46)<0.0011.71 (1.55–1.88)<0.001
 HRadjusted (95% CI)1.00 (referent)9.54 (4.70–19.35)<0.0011.78 (1.57–2.03)<0.001
Lung cancer
 Person-years71 845607877 750
 Mortality rate per 10 000 person-years10.631.312.2
 HRcrude (95% CI)1.00 (referent)2.81 (1.70–4.65)<0.0011.35 (1.20–1.52)<0.001
 HRadjusted (95% CI)1.00 (referent)1.84 (1.09–3.12)0.0231.21 (1.06–1.38)0.006
All lung diseases
 Person-years71 845607877 750
 Mortality rate per 10 000 person-years18.560.922.1
 HRcrude (95% CI)1.00 (referent)3.16 (2.20–4.56)<0.0011.42 (1.32–1.53)<0.001
 HRadjusted (95% CI)1.00 (referent)2.25 (1.54–3.30)<0.0011.34 (1.23–1.46)<0.001
  • The end points were defined by an underlying cause of death of respiratory disease (J00–J99), lung cancer (C33–C34) and, combining these, all lung disease. We also specifically examined mortality due to CLRD (J40–47), which was defined as deaths with COPD, emphysema, chronic bronchitis or asthma as the underlying cause, or, in the context of pneumonia as the underlying cause (J12–18), with these diseases (J40–47) recorded as a contributing cause.

  • For per cent emphysema, HRs reported per IQR (4.5%), which is equivalent to the difference between the third quartile (5.7%) and the first quartile (1.2%) of per cent emphysema. Models adjusted for baseline age, sex, race/ethnicity, body mass index, site, smoking status, pack-years of smoking, coronary artery calcium score and educational attainment. Upper limit of normal for per cent emphysema defined by reference equations.

  • CLRD, chronic lower respiratory disease.