TABLE 2

All-cause mortality hazard ratios (HRs) from Cox proportional hazard regressions (n=59 533)

Unadjusted HR
(95% CI)
p-valueAHR
(95% CI)
p-value
Exposure
 SABA canisters per year
  01.23 (1.16–1.29)<0.00011.07 (0.98–1.17)0.15
  1–21.00(Reference)1.00(Reference)
  3–51.14 (1.05–1.25)0.001.11 (1.02–1.22)0.02
  ≥61.52 (1.38–1.67)<0.00011.56 (1.41–1.71)<0.0001
Covariate
 Deprivation quintile
  1 (least)1.00(Reference)1.00(Reference)
  21.09 (1.01–1.17)0.021.03 (0.95–1.11)0.47
  31.12 (1.04–1.21)0.001.00 (0.93–1.08)0.97
  41.21 (1.13–1.3)<0.00011.03 (0.96–1.11)0.44
  5 (most)1.33 (1.23–1.42)<0.00011.11 (1.04–1.19)0.00
 Dependency quintile
  1 (least)1.00(Reference)1.00(Reference)
  21.10 (1.01–1.20)0.021.03 (0.95–1.12)0.52
  31.15 (1.06–1.25)0.001.08 (0.99–1.17)0.07
  41.30 (1.20–1.41)<0.00011.16 (1.07–1.26)0.00
  5 (most)1.67 (1.56–1.8)<0.00011.25 (1.16–1.34)<0.0001
 Age group at index date1.17 (1.16–1.17)<0.00011.16 (1.16–1.17)<0.0001
 Male sex (reference=female)1.09 (1.04–1.14)0.001.30 (1.24–1.36)<0.0001
 Rural residence
 (reference=urban)
1.05 (0.97–1.13)0.241.19 (1.10–1.28)<0.0001
 ICS only or ICS-LABA1.00(Reference)1.00(Reference)
 No asthma medication1.43 (1.35–1.51)<0.00011.26 (1.18–1.34)<0.0001
 SABA only1.29 (1.20–1.39)<0.00011.19 (1.08–1.31)0.00
 Other asthma medication1.26 (1.19–1.35)<0.00011.16 (1.07–1.26)0.00
 Asthma exacerbation in
 baseline period
0.90 (0.69–1.16)0.401.08 (0.83–1.39)0.58
Number of comorbidities
  01.00(Reference)1.00(Reference)
  11.63 (1.51–1.76)<0.00011.25 (1.15–1.34)<0.0001
  22.54 (2.36–2.75)<0.00011.66 (1.54–1.79)<0.0001
  ≥33.75 (3.46–4.06)<0.00012.13 (1.96–2.31)<0.0001

AHR: adjusted hazard ratio; SABA: short-acting β2-agonist; ICS: inhaled corticosteroid; ICS-LABA: ICS long-acting β2-agonist.